zshall
ZSHALL(1) ZSHALL(1)
NAME
zshall - the Z shell meta-man page
OVERVIEW
Because zsh contains many features, the zsh manual has been split into
a number of sections. This manual page includes all the separate man-
ual pages in the following order:
zshmisc Anything not fitting into the other sections
zshexpn Zsh command and parameter expansion
zshparam Zsh parameters
zshoptions Zsh options
zshbuiltins Zsh built-in functions
zshzle Zsh command line editing
zshcompwid Zsh completion widgets
zshcompsys Zsh completion system
zshcompctl Zsh completion control
zshmodules Zsh loadable modules
zshzftpsys Zsh built-in FTP client
DESCRIPTION
Zsh is a UNIX command interpreter (shell) usable as an interactive
login shell and as a shell script command processor. Of the standard
shells, zsh most closely resembles ksh but includes many enhancements.
Zsh has command line editing, builtin spelling correction, pro-
grammable command completion, shell functions (with autoloading), a
history mechanism, and a host of other features.
AUTHOR
Zsh was originally written by Paul Falstad <pf@zsh.org>. Zsh is now
maintained by the members of the zsh-workers mailing list <zsh-work-
ers@sunsite.dk>. The development is currently coordinated by Peter
Stephenson <pws@zsh.org>. The coordinator can be contacted at <coor-
dinator@zsh.org>, but matters relating to the code should generally go
to the mailing list.
AVAILABILITY
Zsh is available from the following anonymous FTP sites. These mirror
sites are kept frequently up to date. The sites marked with (H) may
be mirroring ftp.cs.elte.hu instead of the primary site.
Primary site
ftp://ftp.zsh.org/pub/zsh/
http://www.zsh.org/pub/zsh/
Australia
ftp://ftp.zsh.org/pub/zsh/
http://www.zsh.org/pub/zsh/
Denmark
ftp://sunsite.dk/pub/unix/shells/zsh/
Finland
ftp://ftp.funet.fi/pub/unix/shells/zsh/
Germany
ftp://ftp.fu-berlin.de/pub/unix/shells/zsh/ (H)
ftp://ftp.gmd.de/packages/zsh/
ftp://ftp.uni-trier.de/pub/unix/shell/zsh/
Hungary
ftp://ftp.cs.elte.hu/pub/zsh/
http://www.cs.elte.hu/pub/zsh/
ftp://ftp.kfki.hu/pub/packages/zsh/
Israel
ftp://ftp.math.technion.ac.il/pub/zsh/
http://www.math.technion.ac.il/pub/zsh/
Japan
ftp://ftp.win.ne.jp/pub/shell/zsh/
ftp://ftp.ayamura.org/pub/zsh/
Korea
ftp://linux.sarang.net/mirror/system/shell/zsh/
Netherlands
ftp://ftp.demon.nl/pub/mirrors/zsh/
Norway
ftp://ftp.uit.no/pub/unix/shells/zsh/
Poland
ftp://sunsite.icm.edu.pl/pub/unix/shells/zsh/
Romania
ftp://ftp.roedu.net/pub/mirrors/ftp.zsh.org/pub/zsh/
ftp://ftp.kappa.ro/pub/mirrors/ftp.zsh.org/pub/zsh/
Slovenia
ftp://ftp.siol.net/mirrors/zsh/
Sweden
ftp://ftp.lysator.liu.se/pub/unix/zsh/
UK
ftp://ftp.net.lut.ac.uk/zsh/
ftp://sunsite.org.uk/packages/zsh/
USA
ftp://uiarchive.uiuc.edu/mirrors/ftp/ftp.zsh.org/pub/
ftp://ftp.rge.com/pub/shells/zsh/
http://zsh.disillusion.org/
http://foad.org/zsh/
The up-to-date source code is available via anonymous CVS from Source-
forge. See http://sourceforge.net/projects/zsh/ for details.
MAILING LISTS
Zsh has 3 mailing lists:
<zsh-announce@sunsite.dk>
Announcements about releases, major changes in the shell and
the monthly posting of the Zsh FAQ. (moderated)
<zsh-users@sunsite.dk>
User discussions.
<zsh-workers@sunsite.dk>
Hacking, development, bug reports and patches.
To subscribe or unsubscribe, send mail to the associated administra-
tive address for the mailing list.
<zsh-announce-subscribe@sunsite.dk>
<zsh-users-subscribe@sunsite.dk>
<zsh-workers-subscribe@sunsite.dk>
<zsh-announce-unsubscribe@sunsite.dk>
<zsh-users-unsubscribe@sunsite.dk>
<zsh-workers-unsubscribe@sunsite.dk>
YOU ONLY NEED TO JOIN ONE OF THE MAILING LISTS AS THEY ARE NESTED.
All submissions to zsh-announce are automatically forwarded to
zsh-users. All submissions to zsh-users are automatically forwarded
to zsh-workers.
If you have problems subscribing/unsubscribing to any of the mailing
lists, send mail to <listmaster@zsh.org>. The mailing lists are main-
tained by Karsten Thygesen <karthy@kom.auc.dk>.
The mailing lists are archived; the archives can be accessed via the
administrative addresses listed above. There is also a hypertext
archive, maintained by Geoff Wing <gcw@zsh.org>, available at
http://www.zsh.org/mla/.
THE ZSH FAQ
Zsh has a list of Frequently Asked Questions (FAQ), maintained by
Peter Stephenson <pws@zsh.org>. It is regularly posted to the news-
group comp.unix.shell and the zsh-announce mailing list. The latest
version can be found at any of the Zsh FTP sites, or at
http://www.zsh.org/FAQ/. The contact address for FAQ-related matters
is <faqmaster@zsh.org>.
THE ZSH WEB PAGE
Zsh has a web page which is located at http://www.zsh.org/. This is
maintained by Karsten Thygesen <karthy@zsh.org>, of SunSITE Denmark.
The contact address for web-related matters is <webmaster@zsh.org>.
THE ZSH USERGUIDE
A userguide is currently in preparation. It is intended to complement
the manual, with explanations and hints on issues where the manual can
be cabbalistic, hierographic, or downright mystifying (for example,
the word ‘hierographic’ does not exist). It can be viewed in its cur-
rent state at http://zsh.sunsite.dk/Guide/. At the time of writing,
chapters dealing with startup files and their contents and the new
completion system were essentially complete.
THE ZSH WIKI
A ‘wiki’ website for zsh has been created at http://www.zshwiki.org/.
This is a site which can be added to and modified directly by users
without any special permission. You can add your own zsh tips and
configurations.
INVOCATION OPTIONS
The following flags are interpreted by the shell when invoked to
determine where the shell will read commands from:
-c Take the first argument as a command to execute, rather than
reading commands from a script or standard input. If any fur-
ther arguments are given, the first one is assigned to $0,
rather than being used as a positional parameter.
-i Force shell to be interactive.
-s Force shell to read commands from the standard input. If the
-s flag is not present and an argument is given, the first
argument is taken to be the pathname of a script to execute.
After the first one or two arguments have been appropriated as
described above, the remaining arguments are assigned to the posi-
tional parameters.
For further options, which are common to invocation and the set
builtin, see zshoptions(1).
Options may be specified by name using the -o option. -o acts like a
single-letter option, but takes a following string as the option name.
For example,
zsh -x -o shwordsplit scr
runs the script scr, setting the XTRACE option by the corresponding
letter ‘-x’ and the SH_WORD_SPLIT option by name. Options may be
turned off by name by using +o instead of -o. -o can be stacked up
with preceding single-letter options, so for example ‘-xo shwordsplit’
or ‘-xoshwordsplit’ is equivalent to ‘-x -o shwordsplit’.
Options may also be specified by name in GNU long option style,
‘--option-name’. When this is done, ‘-’ characters in the option name
are permitted: they are translated into ‘_’, and thus ignored. So,
for example, ‘zsh --sh-word-split’ invokes zsh with the SH_WORD_SPLIT
option turned on. Like other option syntaxes, options can be turned
off by replacing the initial ‘-’ with a ‘+’; thus ‘+-sh-word-split’ is
equivalent to ‘--no-sh-word-split’. Unlike other option syntaxes,
GNU-style long options cannot be stacked with any other options, so
for example ‘-x-shwordsplit’ is an error, rather than being treated
like ‘-x --shwordsplit’.
The special GNU-style option ‘--version’ is handled; it sends to stan-
dard output the shell’s version information, then exits successfully.
‘--help’ is also handled; it sends to standard output a list of
options that can be used when invoking the shell, then exits success-
fully.
Option processing may be finished, allowing following arguments that
start with ‘-’ or ‘+’ to be treated as normal arguments, in two ways.
Firstly, a lone ‘-’ (or ‘+’) as an argument by itself ends option pro-
cessing. Secondly, a special option ‘--’ (or ‘+-’), which may be
specified on its own (which is the standard POSIX usage) or may be
stacked with preceding options (so ‘-x-’ is equivalent to ‘-x --’).
Options are not permitted to be stacked after ‘--’ (so ‘-x-f’ is an
error), but note the GNU-style option form discussed above, where
‘--shwordsplit’ is permitted and does not end option processing.
Except when the sh/ksh emulation single-letter options are in effect,
the option ‘-b’ (or ‘+b’) ends option processing. ‘-b’ is like ‘--’,
except that further single-letter options can be stacked after the
‘-b’ and will take effect as normal.
COMPATIBILITY
Zsh tries to emulate sh or ksh when it is invoked as sh or ksh respec-
tively; more precisely, it looks at the first letter of the name by
which it was invoked, excluding any initial ‘r’ (assumed to stand for
‘restricted’), and if that is ‘s’ or ‘k’ it will emulate sh or ksh.
Furthermore, if invoked as su (which happens on certain systems when
the shell is executed by the su command), the shell will try to find
an alternative name from the SHELL environment variable and perform
emulation based on that.
In sh and ksh compatibility modes the following parameters are not
special and not initialized by the shell: ARGC, argv, cdpath, fignore,
fpath, HISTCHARS, mailpath, MANPATH, manpath, path, prompt, PROMPT,
PROMPT2, PROMPT3, PROMPT4, psvar, status, watch.
The usual zsh startup/shutdown scripts are not executed. Login shells
source /etc/profile followed by $HOME/.profile. If the ENV environ-
ment variable is set on invocation, $ENV is sourced after the profile
scripts. The value of ENV is subjected to parameter expansion, com-
mand substitution, and arithmetic expansion before being interpreted
as a pathname. Note that the PRIVILEGED option also affects the exe-
cution of startup files.
The following options are set if the shell is invoked as sh or ksh:
NO_BAD_PATTERN, NO_BANG_HIST, NO_BG_NICE, NO_EQUALS, NO_FUNC-
TION_ARGZERO, GLOB_SUBST, NO_GLOBAL_EXPORT, NO_HUP, INTERACTIVE_COM-
MENTS, KSH_ARRAYS, NO_MULTIOS, NO_NOMATCH, NO_NOTIFY, POSIX_BUILTINS,
NO_PROMPT_PERCENT, RM_STAR_SILENT, SH_FILE_EXPANSION, SH_GLOB,
SH_OPTION_LETTERS, SH_WORD_SPLIT. Additionally the BSD_ECHO and
IGNORE_BRACES options are set if zsh is invoked as sh. Also, the
KSH_OPTION_PRINT, LOCAL_OPTIONS, PROMPT_BANG, PROMPT_SUBST and
SINGLE_LINE_ZLE options are set if zsh is invoked as ksh.
RESTRICTED SHELL
When the basename of the command used to invoke zsh starts with the
letter ‘r’ or the ‘-r’ command line option is supplied at invocation,
the shell becomes restricted. Emulation mode is determined after
stripping the letter ‘r’ from the invocation name. The following are
disabled in restricted mode:
· changing directories with the cd builtin
· changing or unsetting the PATH, path, MODULE_PATH, module_path,
SHELL, HISTFILE, HISTSIZE, GID, EGID, UID, EUID, USERNAME,
LD_LIBRARY_PATH, LD_AOUT_LIBRARY_PATH, LD_PRELOAD and
LD_AOUT_PRELOAD parameters
· specifying command names containing /
· specifying command pathnames using hash
· redirecting output to files
· using the exec builtin command to replace the shell with
another command
· using jobs -Z to overwrite the shell process’ argument and
environment space
· using the ARGV0 parameter to override argv[0] for external com-
mands
· turning off restricted mode with set +r or unsetopt RESTRICTED
These restrictions are enforced after processing the startup files.
The startup files should set up PATH to point to a directory of com-
mands which can be safely invoked in the restricted environment. They
may also add further restrictions by disabling selected builtins.
Restricted mode can also be activated any time by setting the
RESTRICTED option. This immediately enables all the restrictions
described above even if the shell still has not processed all startup
files.
STARTUP/SHUTDOWN FILES
Commands are first read from /etc/zshenv; this cannot be overridden.
Subsequent behaviour is modified by the RCS and GLOBAL_RCS options;
the former affects all startup files, while the second only affects
those in the /etc directory. If one of the options is unset at any
point, any subsequent startup file(s) of the corresponding type will
not be read. It is also possible for a file in $ZDOTDIR to re-enable
GLOBAL_RCS. Both RCS and GLOBAL_RCS are set by default.
Commands are then read from $ZDOTDIR/.zshenv. If the shell is a login
shell, commands are read from /etc/zprofile and then $ZDOTDIR/.zpro-
file. Then, if the shell is interactive, commands are read from
/etc/zshrc and then $ZDOTDIR/.zshrc. Finally, if the shell is a login
shell, /etc/zlogin and $ZDOTDIR/.zlogin are read.
When a login shell exits, the files $ZDOTDIR/.zlogout and then
/etc/zlogout are read. This happens with either an explicit exit via
the exit or logout commands, or an implicit exit by reading
end-of-file from the terminal. However, if the shell terminates due
to exec’ing another process, the logout files are not read. These are
also affected by the RCS and GLOBAL_RCS options. Note also that the
RCS option affects the saving of history files, i.e. if RCS is unset
when the shell exits, no history file will be saved.
If ZDOTDIR is unset, HOME is used instead. Those files listed above
as being in /etc may be in another directory, depending on the instal-
lation.
As /etc/zshenv is run for all instances of zsh, it is important that
it be kept as small as possible. In particular, it is a good idea to
put code that does not need to be run for every single shell behind a
test of the form ‘if [[ -o rcs ]]; then ...’ so that it will not be
executed when zsh is invoked with the ‘-f’ option.
Any of these files may be pre-compiled with the zcompile builtin com-
mand (see zshbuiltins(1)). If a compiled file exists (named for the
original file plus the .zwc extension) and it is newer than the origi-
ZSHMISC(1) ZSHMISC(1)
nal file, the compiled file will be used instead.
NAME
zshmisc - everything and then some
SIMPLE COMMANDS & PIPELINES
A simple command is a sequence of optional parameter assignments fol-
lowed by blank-separated words, with optional redirections inter-
spersed. The first word is the command to be executed, and the
remaining words, if any, are arguments to the command. If a command
name is given, the parameter assignments modify the environment of the
command when it is executed. The value of a simple command is its
exit status, or 128 plus the signal number if terminated by a signal.
For example,
echo foo
is a simple command with arguments.
A pipeline is either a simple command, or a sequence of two or more
simple commands where each command is separated from the next by ‘|’
or ‘|&’. Where commands are separated by ‘|’, the standard output of
the first command is connected to the standard input of the next.
‘|&’ is shorthand for ‘2>&1 |’, which connects both the standard out-
put and the standard error of the command to the standard input of the
next. The value of a pipeline is the value of the last command,
unless the pipeline is preceded by ‘!’ in which case the value is the
logical inverse of the value of the last command. For example,
echo foo | sed ’s/foo/bar/’
is a pipeline, where the output (‘foo’ plus a newline) of the first
command will be passed to the input of the second.
If a pipeline is preceded by ‘coproc’, it is executed as a coprocess;
a two-way pipe is established between it and the parent shell. The
shell can read from or write to the coprocess by means of the ‘>&p’
and ‘<&p’ redirection operators or with ‘print -p’ and ‘read -p’. A
pipeline cannot be preceded by both ‘coproc’ and ‘!’. If job control
is active, the coprocess can be treated in other than input and output
as an ordinary background job.
A sublist is either a single pipeline, or a sequence of two or more
pipelines separated by ‘&&’ or ‘||’. If two pipelines are separated
by ‘&&’, the second pipeline is executed only if the first succeeds
(returns a zero value). If two pipelines are separated by ‘||’, the
second is executed only if the first fails (returns a nonzero value).
Both operators have equal precedence and are left associative. The
value of the sublist is the value of the last pipeline executed. For
example,
dmesg | grep panic && print yes
is a sublist consisting of two pipelines, the second just a simple
command which will be executed if and only if the grep command returns
a zero value. If it does not, the value of the sublist is that return
value, else it is the value returned by the print (almost certainly
zero).
A list is a sequence of zero or more sublists, in which each sublist
is terminated by ‘;’, ‘&’, ‘&|’, ‘&!’, or a newline. This terminator
may optionally be omitted from the last sublist in the list when the
list appears as a complex command inside ‘(...)’ or ‘{...}’. When a
sublist is terminated by ‘;’ or newline, the shell waits for it to
finish before executing the next sublist. If a sublist is terminated
by a ‘&’, ‘&|’, or ‘&!’, the shell executes the last pipeline in it in
the background, and does not wait for it to finish (note the differ-
ence from other shells which execute the whole sublist in the back-
ground). A backgrounded pipeline returns a status of zero.
More generally, a list can be seen as a set of any shell commands
whatsoever, including the complex commands below; this is implied
wherever the word ‘list’ appears in later descriptions. For example,
the commands in a shell function form a special sort of list.
PRECOMMAND MODIFIERS
A simple command may be preceded by a precommand modifier, which will
alter how the command is interpreted. These modifiers are shell
builtin commands with the exception of nocorrect which is a reserved
word.
- The command is executed with a ‘-’ prepended to its argv[0]
string.
noglob Filename generation (globbing) is not performed on any of the
words.
nocorrect
Spelling correction is not done on any of the words. This must
appear before any other precommand modifier, as it is inter-
preted immediately, before any parsing is done. It has no
effect in non-interactive shells.
exec The command is executed in the parent shell without forking.
command
The command word is taken to be the name of an external com-
mand, rather than a shell function or builtin.
builtin
The command word is taken to be the name of a builtin command,
rather than a shell function or external command.
COMPLEX COMMANDS
A complex command in zsh is one of the following:
if list then list [ elif list then list ] ... [ else list ] fi
The if list is executed, and if it returns a zero exit status,
the then list is executed. Otherwise, the elif list is exe-
cuted and if its value is zero, the then list is executed. If
each elif list returns nonzero, the else list is executed.
for name ... [ in word ... ] term do list done
where term is at least one newline or ;. Expand the list of
words, and set the parameter name to each of them in turn, exe-
cuting list each time. If the in word is omitted, use the
positional parameters instead of the words.
More than one parameter name can appear before the list of
words. If N names are given, then on each execution of the
loop the next N words are assigned to the corresponding parame-
ters. If there are more names than remaining words, the
remaining parameters are each set to the empty string. Execu-
tion of the loop ends when there is no remaining word to assign
to the first name. It is only possible for in to appear as the
first name in the list, else it will be treated as marking the
end of the list.
for (( [expr1] ; [expr2] ; [expr3] )) do list done
The arithmetic expression expr1 is evaluated first (see the
section ‘Arithmetic Evaluation’). The arithmetic expression
expr2 is repeatedly evaluated until it evaluates to zero and
when non-zero, list is executed and the arithmetic expression
expr3 evaluated. If any expression is omitted, then it behaves
as if it evaluated to 1.
while list do list done
Execute the do list as long as the while list returns a zero
exit status.
until list do list done
Execute the do list as long as until list returns a nonzero
exit status.
repeat word do list done
word is expanded and treated as an arithmetic expression, which
must evaluate to a number n. list is then executed n times.
case word in [ [(] pattern [ | pattern ] ... ) list (;;|;&) ] ... esac
Execute the list associated with the first pattern that matches
word, if any. The form of the patterns is the same as that
used for filename generation. See the section ‘Filename Gener-
ation’. If the list that is executed is terminated with ;&
rather than ;;, the following list is also executed. This con-
tinues until either a list is terminated with ;; or the esac is
reached.
select name [ in word ... term ] do list done
where term is one or more newline or ; to terminate the words.
Print the set of words, each preceded by a number. If the in
word is omitted, use the positional parameters. The PROMPT3
prompt is printed and a line is read from the line editor if
the shell is interactive and that is active, or else standard
input. If this line consists of the number of one of the
listed words, then the parameter name is set to the word corre-
sponding to this number. If this line is empty, the selection
list is printed again. Otherwise, the value of the parameter
name is set to null. The contents of the line read from stan-
dard input is saved in the parameter REPLY. list is executed
for each selection until a break or end-of-file is encountered.
( list )
Execute list in a subshell. Traps set by the trap builtin are
reset to their default values while executing list.
{ list }
Execute list.
function word ... [ () ] [ term ] { list }
word ... () [ term ] { list }
word ... () [ term ] command
where term is one or more newline or ;. Define a function
which is referenced by any one of word. Normally, only one
word is provided; multiple words are usually only useful for
setting traps. The body of the function is the list between
the { and }. See the section ‘Functions’.
If the option SH_GLOB is set for compatibility with other
shells, then whitespace may appear between between the left and
right parentheses when there is a single word; otherwise, the
parentheses will be treated as forming a globbing pattern in
that case.
time [ pipeline ]
The pipeline is executed, and timing statistics are reported on
the standard error in the form specified by the TIMEFMT
parameter. If pipeline is omitted, print statistics about the
shell process and its children.
[[ exp ]]
Evaluates the conditional expression exp and return a zero exit
status if it is true. See the section ‘Conditional Expres-
sions’ for a description of exp.
ALTERNATE FORMS FOR COMPLEX COMMANDS
Many of zsh’s complex commands have alternate forms. These particular
versions of complex commands should be considered deprecated and may
be removed in the future. The versions in the previous section should
be preferred instead.
The short versions below only work if sublist is of the form ‘{ list
}’ or if the SHORT_LOOPS option is set. For the if, while and until
commands, in both these cases the test part of the loop must also be
suitably delimited, such as by ‘[[ ... ]]’ or ‘(( ... ))’, else the
end of the test will not be recognized. For the for, repeat, case and
select commands no such special form for the arguments is necessary,
but the other condition (the special form of sublist or use of the
SHORT_LOOPS option) still applies.
if list { list } [ elif list { list } ] ... [ else { list } ]
An alternate form of if. The rules mean that
if [[ -o ignorebraces ]] {
print yes
}
works, but
if true { # Does not work!
print yes
}
does not, since the test is not suitably delimited.
if list sublist
A short form of the alternate ‘if’. The same limitations on
the form of list apply as for the previous form.
for name ... ( word ... ) sublist
A short form of for.
for name ... [ in word ... ] term sublist
where term is at least one newline or ;. Another short form of
for.
for (( [expr1] ; [expr2] ; [expr3] )) sublist
A short form of the arithmetic for command.
foreach name ... ( word ... ) list end
Another form of for.
while list { list }
An alternative form of while. Note the limitations on the form
of list mentioned above.
until list { list }
An alternative form of until. Note the limitations on the form
of list mentioned above.
repeat word sublist
This is a short form of repeat.
case word { [ [(] pattern [ | pattern ] ... ) list (;;|;&) ] ... }
An alternative form of case.
select name [ in word term ] sublist
where term is at least one newline or ;. A short form of
select.
RESERVED WORDS
The following words are recognized as reserved words when used as the
first word of a command unless quoted or disabled using disable -r:
do done esac then elif else fi for case if while function repeat time
until select coproc nocorrect foreach end ! [[ { }
Additionally, ‘}’ is recognized in any position if the IGNORE_BRACES
option is not set.
COMMENTS
In noninteractive shells, or in interactive shells with the INTERAC-
TIVE_COMMENTS option set, a word beginning with the third character of
the histchars parameter (‘#’ by default) causes that word and all the
following characters up to a newline to be ignored.
ALIASING
Every token in the shell input is checked to see if there is an alias
defined for it. If so, it is replaced by the text of the alias if it
is in command position (if it could be the first word of a simple com-
mand), or if the alias is global. If the text ends with a space, the
next word in the shell input is treated as though it were in command
position for purposes of alias expansion. An alias is defined using
the alias builtin; global aliases may be defined using the -g option
to that builtin.
Alias expansion is done on the shell input before any other expansion
except history expansion. Therefore, if an alias is defined for the
word foo, alias expansion may be avoided by quoting part of the word,
e.g. \foo. But there is nothing to prevent an alias being defined for
\foo as well.
QUOTING
A character may be quoted (that is, made to stand for itself) by pre-
ceding it with a ‘\’. ‘\’ followed by a newline is ignored.
A string enclosed between ‘$’’ and ‘’’ is processed the same way as
the string arguments of the print builtin, and the resulting string is
considered to be entirely quoted. A literal ‘’’ character can be
included in the string by using the ‘\’’ escape.
All characters enclosed between a pair of single quotes (’’) that is
not preceded by a ‘$’ are quoted. A single quote cannot appear within
single quotes unless the option RC_QUOTES is set, in which case a pair
of single quotes are turned into a single quote. For example,
print ’’’’
outputs nothing apart from a newline if RC_QUOTES is not set, but one
single quote if it is set.
Inside double quotes (""), parameter and command substitution occur,
and ‘\’ quotes the characters ‘\’, ‘‘’, ‘"’, and ‘$’.
REDIRECTION
If a command is followed by & and job control is not active, then the
default standard input for the command is the empty file /dev/null.
Otherwise, the environment for the execution of a command contains the
file descriptors of the invoking shell as modified by input/output
specifications.
The following may appear anywhere in a simple command or may precede
or follow a complex command. Expansion occurs before word or digit is
used except as noted below. If the result of substitution on word
produces more than one filename, redirection occurs for each separate
filename in turn.
< word Open file word for reading as standard input.
<> word
Open file word for reading and writing as standard input. If
the file does not exist then it is created.
> word Open file word for writing as standard output. If the file
does not exist then it is created. If the file exists, and the
CLOBBER option is unset, this causes an error; otherwise, it is
truncated to zero length.
>| word
>! word
Same as >, except that the file is truncated to zero length if
it exists, even if CLOBBER is unset.
>> word
Open file word for writing in append mode as standard output.
If the file does not exist, and the CLOBBER option is unset,
this causes an error; otherwise, the file is created.
>>| word
>>! word
Same as >>, except that the file is created if it does not
exist, even if CLOBBER is unset.
<<[-] word
The shell input is read up to a line that is the same as word,
or to an end-of-file. No parameter expansion, command substi-
tution or filename generation is performed on word. The
resulting document, called a here-document, becomes the stan-
dard input.
If any character of word is quoted with single or double quotes
or a ‘\’, no interpretation is placed upon the characters of
the document. Otherwise, parameter and command substitution
occurs, ‘\’ followed by a newline is removed, and ‘\’ must be
used to quote the characters ‘\’, ‘$’, ‘‘’ and the first char-
acter of word.
If <<- is used, then all leading tabs are stripped from word
and from the document.
<<< word
Perform shell expansion on word and pass the result to standard
input. This is known as a here-string.
<& number
>& number
The standard input/output is duplicated from file descriptor
number (see dup2(2)).
<& -
>& - Close the standard input/output.
<& p
>& p The input/output from/to the coprocess is moved to the standard
input/output.
>& word
&> word
(Except where ‘>& word’ matches one of the above syntaxes; ‘&>’
can always be used to avoid this ambiguity.) Redirects both
standard output and standard error (file descriptor 2) in the
manner of ‘> word’. Note that this does not have the same
effect as ‘> word 2>&1’ in the presence of multios (see the
section below).
>&| word
>&! word
&>| word
&>! word
Redirects both standard output and standard error (file
descriptor 2) in the manner of ‘>| word’.
>>& word
&>> word
Redirects both standard output and standard error (file
descriptor 2) in the manner of ‘>> word’.
>>&| word
>>&! word
&>>| word
&>>! word
Redirects both standard output and standard error (file
descriptor 2) in the manner of ‘>>| word’.
If one of the above is preceded by a digit, then the file descriptor
referred to is that specified by the digit instead of the default 0 or
1. The order in which redirections are specified is significant. The
shell evaluates each redirection in terms of the (file descriptor,
file) association at the time of evaluation. For example:
... 1>fname 2>&1
first associates file descriptor 1 with file fname. It then asso-
ciates file descriptor 2 with the file associated with file descriptor
1 (that is, fname). If the order of redirections were reversed, file
descriptor 2 would be associated with the terminal (assuming file
descriptor 1 had been) and then file descriptor 1 would be associated
with file fname.
The ‘|&’ command separator described in Simple Commands & Pipelines in
zshmisc(1) is a shorthand for ‘2>&1 |’.
For output redirections only, if word is of the form ‘>(list)’ then
the output is piped to the command represented by list. See Process
Substitution in zshexpn(1).
MULTIOS
If the user tries to open a file descriptor for writing more than
once, the shell opens the file descriptor as a pipe to a process that
copies its input to all the specified outputs, similar to tee, pro-
vided the MULTIOS option is set, as it is by default. Thus:
date >foo >bar
writes the date to two files, named ‘foo’ and ‘bar’. Note that a pipe
is an implicit redirection; thus
date >foo | cat
writes the date to the file ‘foo’, and also pipes it to cat.
If the MULTIOS option is set, the word after a redirection operator is
also subjected to filename generation (globbing). Thus
: > *
will truncate all files in the current directory, assuming there’s at
least one. (Without the MULTIOS option, it would create an empty file
called ‘*’.) Similarly, you can do
echo exit 0 >> *.sh
If the user tries to open a file descriptor for reading more than
once, the shell opens the file descriptor as a pipe to a process that
copies all the specified inputs to its output in the order specified,
similar to cat, provided the MULTIOS option is set. Thus
sort <foo <fubar
or even
sort <f{oo,ubar}
is equivalent to ‘cat foo fubar | sort’.
Note that a pipe is an implicit redirection; thus
cat bar | sort <foo
is equivalent to ‘cat bar foo | sort’ (note the order of the inputs).
If the MULTIOS option is unset, each redirection replaces the previous
redirection for that file descriptor. However, all files redirected
to are actually opened, so
echo foo > bar > baz
when MULTIOS is unset will truncate bar, and write ‘foo’ into baz.
There is a problem when an output multio is attached to an external
program. A simple example shows this:
cat file >file1 >file2
cat file1 file2
Here, it is possible that the second ‘cat’ will not display the full
contents of file1 and file2 (i.e. the original contents of file
repeated twice).
The reason for this is that the multios are spawned after the cat pro-
cess is forked from the parent shell, so the parent shell does not
wait for the multios to finish writing data. This means the command
as shown can exit before file1 and file2 are completely written. As a
workaround, it is possible to run the cat process as part of a job in
the current shell:
{ cat file } >file >file2
Here, the {...} job will pause to wait for both files to be written.
REDIRECTIONS WITH NO COMMAND
When a simple command consists of one or more redirection operators
and zero or more parameter assignments, but no command name, zsh can
behave in several ways.
If the parameter NULLCMD is not set or the option CSH_NULLCMD is set,
an error is caused. This is the csh behavior and CSH_NULLCMD is set
by default when emulating csh.
If the option SH_NULLCMD is set, the builtin ‘:’ is inserted as a com-
mand with the given redirections. This is the default when emulating
sh or ksh.
Otherwise, if the parameter NULLCMD is set, its value will be used as
a command with the given redirections. If both NULLCMD and READNULL-
CMD are set, then the value of the latter will be used instead of that
of the former when the redirection is an input. The default for NULL-
CMD is ‘cat’ and for READNULLCMD is ‘more’. Thus
< file
shows the contents of file on standard output, with paging if that is
a terminal. NULLCMD and READNULLCMD may refer to shell functions.
COMMAND EXECUTION
If a command name contains no slashes, the shell attempts to locate
it. If there exists a shell function by that name, the function is
invoked as described in the section ‘Functions’. If there exists a
shell builtin by that name, the builtin is invoked.
Otherwise, the shell searches each element of $path for a directory
containing an executable file by that name. If the search is unsuc-
cessful, the shell prints an error message and returns a nonzero exit
status.
If execution fails because the file is not in executable format, and
the file is not a directory, it is assumed to be a shell script.
/bin/sh is spawned to execute it. If the program is a file beginning
with ‘#!’, the remainder of the first line specifies an interpreter
for the program. The shell will execute the specified interpreter on
operating systems that do not handle this executable format in the
kernel.
FUNCTIONS
Shell functions are defined with the function reserved word or the
special syntax ‘funcname ()’. Shell functions are read in and stored
internally. Alias names are resolved when the function is read.
Functions are executed like commands with the arguments passed as
positional parameters. (See the section ‘Command Execution’.)
Functions execute in the same process as the caller and share all
files and present working directory with the caller. A trap on EXIT
set inside a function is executed after the function completes in the
environment of the caller.
The return builtin is used to return from function calls.
Function identifiers can be listed with the functions builtin. Func-
tions can be undefined with the unfunction builtin.
AUTOLOADING FUNCTIONS
A function can be marked as undefined using the autoload builtin (or
‘functions -u’ or ‘typeset -fu’). Such a function has no body. When
the function is first executed, the shell searches for its definition
using the elements of the fpath variable. Thus to define functions
for autoloading, a typical sequence is:
fpath=(~/myfuncs $fpath)
autoload myfunc1 myfunc2 ...
The usual alias expansion during reading will be suppressed if the
autoload builtin or its equivalent is given the option -U. This is
recommended for the use of functions supplied with the zsh distribu-
tion. Note that for functions precompiled with the zcompile builtin
command the flag -U must be provided when the .zwc file is created, as
the corresponding information is compiled into the latter.
For each element in fpath, the shell looks for three possible files,
the newest of which is used to load the definition for the function:
element.zwc
A file created with the zcompile builtin command, which is
expected to contain the definitions for all functions in the
directory named element. The file is treated in the same man-
ner as a directory containing files for functions and is
searched for the definition of the function. If the defini-
tion is not found, the search for a definition proceeds with
the other two possibilities described below.
If element already includes a .zwc extension (i.e. the exten-
sion was explicitly given by the user), element is searched for
the definition of the function without comparing its age to
that of other files; in fact, there does not need to be any
directory named element without the suffix. Thus including an
element such as ‘/usr/local/funcs.zwc’ in fpath will speed up
the search for functions, with the disadvantage that functions
included must be explicitly recompiled by hand before the shell
notices any changes.
element/function.zwc
A file created with zcompile, which is expected to contain the
definition for function. It may include other function defini-
tions as well, but those are neither loaded nor executed; a
file found in this way is searched only for the definition of
function.
element/function
A file of zsh command text, taken to be the definition for
function.
In summary, the order of searching is, first, in the parents of direc-
tories in fpath for the newer of either a compiled directory or a
directory in fpath; second, if more than one of these contains a defi-
nition for the function that is sought, the leftmost in the fpath is
chosen; and third, within a directory, the newer of either a compiled
function or an ordinary function definition is used.
If the KSH_AUTOLOAD option is set, or the file contains only a simple
definition of the function, the file’s contents will be executed.
This will normally define the function in question, but may also per-
form initialization, which is executed in the context of the function
execution, and may therefore define local parameters. It is an error
if the function is not defined by loading the file.
Otherwise, the function body (with no surrounding ‘funcname() {...}’)
is taken to be the complete contents of the file. This form allows
the file to be used directly as an executable shell script. If pro-
cessing of the file results in the function being re-defined, the
function itself is not re-executed. To force the shell to perform
initialization and then call the function defined, the file should
contain initialization code (which will be executed then discarded) in
addition to a complete function definition (which will be retained for
subsequent calls to the function), and a call to the shell function,
including any arguments, at the end.
For example, suppose the autoload file func contains
func() { print This is func; }
print func is initialized
then ‘func; func’ with KSH_AUTOLOAD set will produce both messages on
the first call, but only the message ‘This is func’ on the second and
subsequent calls. Without KSH_AUTOLOAD set, it will produce the ini-
tialization message on the first call, and the other message on the
second and subsequent calls.
It is also possible to create a function that is not marked as
autoloaded, but which loads its own definition by searching fpath, by
using ‘autoload -X’ within a shell function. For example, the follow-
ing are equivalent:
myfunc() {
autoload -X
}
myfunc args...
and
unfunction myfunc # if myfunc was defined
autoload myfunc
myfunc args...
In fact, the functions command outputs ‘builtin autoload -X’ as the
body of an autoloaded function. This is done so that
eval "$(functions)"
produces a reasonable result. A true autoloaded function can be iden-
tified by the presence of the comment ‘# undefined’ in the body,
because all comments are discarded from defined functions.
To load the definition of an autoloaded function myfunc without exe-
cuting myfunc, use:
autoload +X myfunc
SPECIAL FUNCTIONS
The following functions, if defined, have special meaning to the
shell:
chpwd Executed whenever the current working directory is changed.
periodic
If the parameter PERIOD is set, this function is executed every
$PERIOD seconds, just before a prompt.
precmd Executed before each prompt.
preexec
Executed just after a command has been read and is about to be
executed. If the history mechanism is active (and the line was
not discarded from the history buffer), the string that the
user typed is passed as the first argument, otherwise it is an
empty string. The actual command that will be executed
(including expanded aliases) is passed in two different forms:
the second argument is a single-line, size-limited version of
the command (with things like function bodies elided); the
third argument contains the full text that is being executed.
TRAPNAL
If defined and non-null, this function will be executed when-
ever the shell catches a signal SIGNAL, where NAL is a signal
name as specified for the kill builtin. The signal number will
be passed as the first parameter to the function.
If a function of this form is defined and null, the shell and
processes spawned by it will ignore SIGNAL.
TRAPDEBUG
Executed after each command.
TRAPEXIT
Executed when the shell exits, or when the current function
exits if defined inside a function.
TRAPZERR
Executed whenever a command has a non-zero exit status. How-
ever, the function is not executed if the command occurred in a
sublist followed by ‘&&’ or ‘||’; only the final command in a
sublist of this type causes the trap to be executed.
The functions beginning ‘TRAP’ may alternatively be defined with the
trap builtin: this may be preferable for some uses, as they are then
run in the environment of the calling process, rather than in their
own function environment. Apart from the difference in calling proce-
dure and the fact that the function form appears in lists of func-
tions, the forms
TRAPNAL() {
# code
}
and
trap ’
# code
are equivalent.
JOBS
If the MONITOR option is set, an interactive shell associates a job
with each pipeline. It keeps a table of current jobs, printed by the
jobs command, and assigns them small integer numbers. When a job is
started asynchronously with ‘&’, the shell prints a line which looks
like:
[1] 1234
indicating that the job which was started asynchronously was job num-
ber 1 and had one (top-level) process, whose process ID was 1234.
If a job is started with ‘&|’ or ‘&!’, then that job is immediately
disowned. After startup, it does not have a place in the job table,
and is not subject to the job control features described here.
If you are running a job and wish to do something else you may hit the
key ^Z (control-Z) which sends a TSTP signal to the current job: this
key may be redefined by the susp option of the external stty command.
The shell will then normally indicate that the job has been ‘sus-
pended’, and print another prompt. You can then manipulate the state
of this job, putting it in the background with the bg command, or run
some other commands and then eventually bring the job back into the
foreground with the foreground command fg. A ^Z takes effect immedi-
ately and is like an interrupt in that pending output and unread input
are discarded when it is typed.
A job being run in the background will suspend if it tries to read
from the terminal. Background jobs are normally allowed to produce
output, but this can be disabled by giving the command ‘stty tostop’.
If you set this tty option, then background jobs will suspend when
they try to produce output like they do when they try to read input.
When a command is suspended and continued later with the fg or wait
builtins, zsh restores tty modes that were in effect when it was sus-
pended. This (intentionally) does not apply if the command is contin-
ued via ‘kill -CONT’, nor when it is continued with bg.
There are several ways to refer to jobs in the shell. A job can be
referred to by the process ID of any process of the job or by one of
the following:
%number
The job with the given number.
%string
Any job whose command line begins with string.
%?string
Any job whose command line contains string.
%% Current job.
%+ Equivalent to ‘%%’.
%- Previous job.
The shell learns immediately whenever a process changes state. It
normally informs you whenever a job becomes blocked so that no further
progress is possible. If the NOTIFY option is not set, it waits until
just before it prints a prompt before it informs you.
When the monitor mode is on, each background job that completes trig-
gers any trap set for CHLD.
When you try to leave the shell while jobs are running or suspended,
you will be warned that ‘You have suspended (running) jobs’. You may
use the jobs command to see what they are. If you do this or immedi-
ately try to exit again, the shell will not warn you a second time;
the suspended jobs will be terminated, and the running jobs will be
sent a SIGHUP signal, if the HUP option is set.
To avoid having the shell terminate the running jobs, either use the
nohup command (see nohup(1)) or the disown builtin.
SIGNALS
The INT and QUIT signals for an invoked command are ignored if the
command is followed by ‘&’ and the MONITOR option is not active. Oth-
erwise, signals have the values inherited by the shell from its parent
(but see the TRAPNAL special functions in the section ‘Functions’).
ARITHMETIC EVALUATION
The shell can perform integer and floating point arithmetic, either
using the builtin let, or via a substitution of the form $((...)).
For integers, the shell is usually compiled to use 8-byte precision
where this is available, otherwise precision is 4 bytes. This can be
tested, for example, by giving the command ‘print - $(( 12345678901
))’; if the number appears unchanged, the precision is at least 8
bytes. Floating point arithmetic is always double precision.
The let builtin command takes arithmetic expressions as arguments;
each is evaluated separately. Since many of the arithmetic operators,
as well as spaces, require quoting, an alternative form is provided:
for any command which begins with a ‘((’, all the characters until a
matching ‘))’ are treated as a quoted expression and arithmetic expan-
sion performed as for an argument of let. More precisely, ‘((...))’
is equivalent to ‘let "..."’. For example, the following statement
(( val = 2 + 1 ))
is equivalent to
let "val = 2 + 1"
both assigning the value 3 to the shell variable val and returning a
zero status.
Integers can be in bases other than 10. A leading ‘0x’ or ‘0X’
denotes hexadecimal. Integers may also be of the form ‘base#n’, where
base is a decimal number between two and thirty-six representing the
arithmetic base and n is a number in that base (for example, ‘16#ff’
is 255 in hexadecimal). The base# may also be omitted, in which case
base 10 is used. For backwards compatibility the form ‘[base]n’ is
also accepted.
It is also possible to specify a base to be used for output in the
form ‘[#base]’, for example ‘[#16]’. This is used when outputting
arithmetical substitutions or when assigning to scalar parameters, but
an explicitly defined integer or floating point parameter will not be
affected. If an integer variable is implicitly defined by an arith-
metic expression, any base specified in this way will be set as the
variable’s output arithmetic base as if the option ‘-i base’ to the
typeset builtin had been used. The expression has no precedence and
if it occurs more than once in a mathematical expression, the last
encountered is used. For clarity it is recommended that it appear at
the beginning of an expression. As an example:
typeset -i 16 y
print $(( [#8] x = 32, y = 32 ))
print $x $y
outputs first ‘8#40’, the rightmost value in the given output base,
and then ‘8#40 16#20’, because y has been explicitly declared to have
output base 16, while x (assuming it does not already exist) is
implicitly typed by the arithmetic evaluation, where it acquires the
output base 8.
If the C_BASES option is set, hexadecimal numbers in the standard C
format, for example 0xFF instead of the usual ‘16#FF’. If the option
OCTAL_ZEROES is also set (it is not by default), octal numbers will be
treated similarly and hence appear as ‘077’ instead of ‘8#77’. This
option has no effect on the output of bases other than hexadecimal and
octal, and these formats are always understood on input.
When an output base is specified using the ‘[#base]’ syntax, an appro-
priate base prefix will be output if necessary, so that the value out-
put is valid syntax for input. If the # is doubled, for example
‘[##16]’, then no base prefix is output.
Floating point constants are recognized by the presence of a decimal
point or an exponent. The decimal point may be the first character of
the constant, but the exponent character e or E may not, as it will be
taken for a parameter name.
An arithmetic expression uses nearly the same syntax, precedence, and
associativity of expressions in C. The following operators are sup-
ported (listed in decreasing order of precedence):
+ - ! ~ ++ --
unary plus/minus, logical NOT, complement,
{pre,post}{in,de}crement
<< >> bitwise shift left, right
& bitwise AND
^ bitwise XOR
| bitwise OR
** exponentiation
* / % multiplication, division, modulus (remainder)
+ - addition, subtraction
< > <= >=
comparison
== != equality and inequality
&& logical AND
|| ^^ logical OR, XOR
? : ternary operator
= += -= *= /= %= &= ^= |= <<= >>= &&= ||= ^^= **=
assignment
, comma operator
The operators ‘&&’, ‘||’, ‘&&=’, and ‘||=’ are short-circuiting, and
only one of the latter two expressions in a ternary operator is evalu-
ated. Note the precedence of the bitwise AND, OR, and XOR operators.
Mathematical functions can be called with the syntax ‘func(args)’,
where the function decides if the args is used as a string or a
comma-separated list of arithmetic expressions. The shell currently
defines no mathematical functions by default, but the module zsh/math-
func may be loaded with the zmodload builtin to provide standard
floating point mathematical functions.
An expression of the form ‘##x’ where x is any character sequence such
as ‘a’, ‘^A’, or ‘\M-\C-x’ gives the ASCII value of this character and
an expression of the form ‘#foo’ gives the ASCII value of the first
character of the value of the parameter foo. Note that this is dif-
ferent from the expression ‘$#foo’, a standard parameter substitution
which gives the length of the parameter foo. ‘#\’ is accepted instead
of ‘##’, but its use is deprecated.
Named parameters and subscripted arrays can be referenced by name
within an arithmetic expression without using the parameter expansion
syntax. For example,
((val2 = val1 * 2))
assigns twice the value of $val1 to the parameter named val2.
An internal integer representation of a named parameter can be speci-
fied with the integer builtin. Arithmetic evaluation is performed on
the value of each assignment to a named parameter declared integer in
this manner. Assigning a floating point number to an integer results
in rounding down to the next integer.
Likewise, floating point numbers can be declared with the float
builtin; there are two types, differing only in their output format,
as described for the typeset builtin. The output format can be
bypassed by using arithmetic substitution instead of the parameter
substitution, i.e. ‘${float}’ uses the defined format, but
‘$((float))’ uses a generic floating point format.
Promotion of integer to floating point values is performed where nec-
essary. In addition, if any operator which requires an integer (‘~’,
‘&’, ‘|’, ‘^’, ‘%’, ‘<<’, ‘>>’ and their equivalents with assignment)
is given a floating point argument, it will be silently rounded down
to the next integer.
Scalar variables can hold integer or floating point values at differ-
ent times; there is no memory of the numeric type in this case.
If a variable is first assigned in a numeric context without previ-
ously being declared, it will be implicitly typed as integer or float
and retain that type either until the type is explicitly changed or
until the end of the scope. This can have unforeseen consequences.
For example, in the loop
for (( f = 0; f < 1; f += 0.1 )); do
# use $f
done
if f has not already been declared, the first assignment will cause it
to be created as an integer, and consequently the operation ‘f += 0.1’
will always cause the result to be truncated to zero, so that the loop
will fail. A simple fix would be to turn the initialization into ‘f =
0.0’. It is therefore best to declare numeric variables with explicit
types.
CONDITIONAL EXPRESSIONS
A conditional expression is used with the [[ compound command to test
attributes of files and to compare strings. Each expression can be
constructed from one or more of the following unary or binary expres-
sions:
-a file
true if file exists.
-b file
true if file exists and is a block special file.
-c file
true if file exists and is a character special file.
-d file
true if file exists and is a directory.
-e file
true if file exists.
-f file
true if file exists and is a regular file.
-g file
true if file exists and has its setgid bit set.
-h file
true if file exists and is a symbolic link.
-k file
true if file exists and has its sticky bit set.
-n string
true if length of string is non-zero.
-o option
true if option named option is on. option may be a single
character, in which case it is a single letter option name.
(See the section ‘Specifying Options’.)
-p file
true if file exists and is a FIFO special file (named pipe).
-r file
true if file exists and is readable by current process.
-s file
true if file exists and has size greater than zero.
-t fd true if file descriptor number fd is open and associated with a
terminal device. (note: fd is not optional)
-u file
true if file exists and has its setuid bit set.
-w file
true if file exists and is writable by current process.
-x file
true if file exists and is executable by current process. If
file exists and is a directory, then the current process has
permission to search in the directory.
-z string
true if length of string is zero.
-L file
true if file exists and is a symbolic link.
-O file
true if file exists and is owned by the effective user ID of
this process.
-G file
true if file exists and its group matches the effective group
ID of this process.
-S file
true if file exists and is a socket.
-N file
true if file exists and its access time is not newer than its
modification time.
file1 -nt file2
true if file1 exists and is newer than file2.
file1 -ot file2
true if file1 exists and is older than file2.
file1 -ef file2
true if file1 and file2 exist and refer to the same file.
string = pattern
string == pattern
true if string matches pattern. The ‘==’ form is the preferred
one. The ‘=’ form is for backward compatibility and should be
considered obsolete.
string != pattern
true if string does not match pattern.
string1 < string2
true if string1 comes before string2 based on ASCII value of
their characters.
string1 > string2
true if string1 comes after string2 based on ASCII value of
their characters.
exp1 -eq exp2
true if exp1 is numerically equal to exp2.
exp1 -ne exp2
true if exp1 is numerically not equal to exp2.
exp1 -lt exp2
true if exp1 is numerically less than exp2.
exp1 -gt exp2
true if exp1 is numerically greater than exp2.
exp1 -le exp2
true if exp1 is numerically less than or equal to exp2.
exp1 -ge exp2
true if exp1 is numerically greater than or equal to exp2.
( exp )
true if exp is true.
! exp true if exp is false.
exp1 && exp2
true if exp1 and exp2 are both true.
exp1 || exp2
true if either exp1 or exp2 is true.
Normal shell expansion is performed on the file, string and pattern
arguments, but the result of each expansion is constrained to be a
single word, similar to the effect of double quotes. However, pattern
metacharacters are active for the pattern arguments; the patterns are
the same as those used for filename generation, see zshexpn(1), but
there is no special behaviour of ‘/’ nor initial dots, and no glob
qualifiers are allowed.
In each of the above expressions, if file is of the form ‘/dev/fd/n’,
where n is an integer, then the test applied to the open file whose
descriptor number is n, even if the underlying system does not support
the /dev/fd directory.
In the forms which do numeric comparison, the expressions exp undergo
arithmetic expansion as if they were enclosed in $((...)).
For example, the following:
[[ ( -f foo || -f bar ) && $report = y* ]] && print File exists.
tests if either file foo or file bar exists, and if so, if the value
of the parameter report begins with ‘y’; if the complete condition is
true, the message ‘File exists.’ is printed.
PROMPT EXPANSION
Prompt sequences undergo a special form of expansion. This type of
expansion is also available using the -P option to the print builtin.
If the PROMPT_SUBST option is set, the prompt string is first sub-
jected to parameter expansion, command substitution and arithmetic
expansion. See zshexpn(1).
Certain escape sequences may be recognised in the prompt string.
If the PROMPT_BANG option is set, a ‘!’ in the prompt is replaced by
the current history event number. A literal ‘!’ may then be repre-
sented as ‘!!’.
If the PROMPT_PERCENT option is set, certain escape sequences that
start with ‘%’ are expanded. Some escapes take an optional integer
argument, which should appear between the ‘%’ and the next character
of the sequence. The following escape sequences are recognized:
Special characters
%% A ‘%’.
%) A ‘)’.
Login information
%l The line (tty) the user is logged in on, without ‘/dev/’ pre-
fix. If the name starts with ‘/dev/tty’, that prefix is
stripped.
%M The full machine hostname.
%m The hostname up to the first ‘.’. An integer may follow the
‘%’ to specify how many components of the hostname are desired.
With a negative integer, trailing components of the hostname
are shown.
%n $USERNAME.
%y The line (tty) the user is logged in on, without ‘/dev/’ pre-
fix. This does not treat ‘/dev/tty’ names specially.
Shell state
%# A ‘#’ if the shell is running with privileges, a ‘%’ if not.
Equivalent to ‘%(!.#.%%)’. The definition of ‘privileged’, for
these purposes, is that either the effective user ID is zero,
or, if POSIX.1e capabilities are supported, that at least one
capability is raised in either the Effective or Inheritable
capability vectors.
%? The return code of the last command executed just before the
prompt.
%_ The status of the parser, i.e. the shell constructs (like ‘if’
and ‘for’) that have been started on the command line. If given
an integer number that many strings will be printed; zero or
negative or no integer means print as many as there are. This
is most useful in prompts PS2 for continuation lines and PS4
for debugging with the XTRACE option; in the latter case it
will also work non-interactively.
%d
%/ Present working directory ($PWD). If an integer follows the
‘%’, it specifies a number of trailing components of $PWD to
show; zero means the whole path. A negative integer specifies
leading components, i.e. %-1d specifies the first component.
%~ As %d and %/, but if $PWD has a named directory as its prefix,
that part is replaced by a ‘~’ followed by the name of the
directory. If it starts with $HOME, that part is replaced by a
‘~’.
%h
%! Current history event number.
%i The line number currently being executed in the script, sourced
file, or shell function given by %N. This is most useful for
debugging as part of $PS4.
%j The number of jobs.
%L The current value of $SHLVL.
%N The name of the script, sourced file, or shell function that
zsh is currently executing, whichever was started most
recently. If there is none, this is equivalent to the parame-
ter $0. An integer may follow the ‘%’ to specify a number of
trailing path components to show; zero means the full path. A
negative integer specifies leading components.
%c
%.
%C Trailing component of $PWD. An integer may follow the ‘%’ to
get more than one component. Unless ‘%C’ is used, tilde
contraction is performed first. These are deprecated as %c and
%C are equivalent to %1~ and %1/, respectively, while explicit
positive integers have the same effect as for the latter two
sequences.
Date and time
%D The date in yy-mm-dd format.
%T Current time of day, in 24-hour format.
%t
%@ Current time of day, in 12-hour, am/pm format.
%* Current time of day in 24-hour format, with seconds.
%w The date in day-dd format.
%W The date in mm/dd/yy format.
%D{string}
string is formatted using the strftime function. See strf-
time(3) for more details. Three additional codes are avail-
able: %f prints the day of the month, like %e but without any
preceding space if the day is a single digit, and %K/%L corre-
spond to %k/%l for the hour of the day (24/12 hour clock) in
the same way.
Visual effects
%B (%b)
Start (stop) boldface mode.
%E Clear to end of line.
%U (%u)
Start (stop) underline mode.
%S (%s)
Start (stop) standout mode.
%{...%}
Include a string as a literal escape sequence. The string
within the braces should not change the cursor position. Brace
pairs can nest.
Conditional substrings
%v The value of the first element of the psvar array parameter.
Following the ‘%’ with an integer gives that element of the
array. Negative integers count from the end of the array.
%(x.true-text.false-text)
Specifies a ternary expression. The character following the x
is arbitrary; the same character is used to separate the text
for the ‘true’ result from that for the ‘false’ result. This
separator may not appear in the true-text, except as part of a
%-escape sequence. A ‘)’ may appear in the false-text as ‘%)’.
true-text and false-text may both contain arbitrarily-nested
escape sequences, including further ternary expressions.
The left parenthesis may be preceded or followed by a positive
integer n, which defaults to zero. A negative integer will be
multiplied by -1. The test character x may be any of the fol-
lowing:
! True if the shell is running with privileges.
# True if the effective uid of the current process is n.
? True if the exit status of the last command was n.
_ True if at least n shell constructs were started.
C
/ True if the current absolute path has at least n ele-
ments.
c
.
~ True if the current path, with prefix replacement, has
at least n elements.
D True if the month is equal to n (January = 0).
d True if the day of the month is equal to n.
g True if the effective gid of the current process is n.
j True if the number of jobs is at least n.
L True if the SHLVL parameter is at least n.
l True if at least n characters have already been printed
on the current line.
S True if the SECONDS parameter is at least n.
T True if the time in hours is equal to n.
t True if the time in minutes is equal to n.
v True if the array psvar has at least n elements.
w True if the day of the week is equal to n (Sunday = 0).
%<string<
%>string>
%[xstring]
Specifies truncation behaviour for the remainder of the prompt
string. The third, deprecated, form is equivalent to
‘%xstringx’, i.e. x may be ‘<’ or ‘>’. The numeric argument,
which in the third form may appear immediately after the ‘[’,
specifies the maximum permitted length of the various strings
that can be displayed in the prompt. The string will be dis-
played in place of the truncated portion of any string; note
this does not undergo prompt expansion.
The forms with ‘<’ truncate at the left of the string, and the
forms with ‘>’ truncate at the right of the string. For exam-
ple, if the current directory is ‘/home/pike’, the prompt
‘%8<..<%/’ will expand to ‘..e/pike’. In this string, the ter-
minating character (‘<’, ‘>’ or ‘]’), or in fact any character,
may be quoted by a preceding ‘\’; note when using print -P,
however, that this must be doubled as the string is also sub-
ject to standard print processing, in addition to any back-
slashes removed by a double quoted string: the worst case is
therefore ‘print -P "%<\\\\<<..."’.
If the string is longer than the specified truncation length,
it will appear in full, completely replacing the truncated
string.
The part of the prompt string to be truncated runs to the end
of the string, or to the end of the next enclosing group of the
‘%(’ construct, or to the next truncation encountered at the
same grouping level (i.e. truncations inside a ‘%(’ are sepa-
rate), which ever comes first. In particular, a truncation
with argument zero (e.g. ‘%<<’) marks the end of the range of
the string to be truncated while turning off truncation from
there on. For example, the prompt ’%10<...<%~%<<%# ’ will print
a truncated representation of the current directory, followed
by a ‘%’ or ‘#’, followed by a space. Without the ‘%<<’, those
two characters would be included in the string to be truncated.
ZSHEXPN(1) ZSHEXPN(1)
NAME
zshexpn - zsh expansion and substitution
DESCRIPTION
The following types of expansions are performed in the indicated order
in five steps:
History Expansion
This is performed only in interactive shells.
Alias Expansion
Aliases are expanded immediately before the command line is
parsed as explained under Aliasing in zshmisc(1).
Process Substitution
Parameter Expansion
Command Substitution
Arithmetic Expansion
Brace Expansion
These five are performed in one step in left-to-right fashion.
After these expansions, all unquoted occurrences of the charac-
ters ‘\’, ‘’’ and ‘"’ are removed.
Filename Expansion
If the SH_FILE_EXPANSION option is set, the order of expansion
is modified for compatibility with sh and ksh. In that case
filename expansion is performed immediately after alias expan-
sion, preceding the set of five expansions mentioned above.
Filename Generation
This expansion, commonly referred to as globbing, is always
done last.
The following sections explain the types of expansion in detail.
HISTORY EXPANSION
History expansion allows you to use words from previous command lines
in the command line you are typing. This simplifies spelling correc-
tions and the repetition of complicated commands or arguments. Imme-
diately before execution, each command is saved in the history list,
the size of which is controlled by the HISTSIZE parameter. The one
most recent command is always retained in any case. Each saved com-
mand in the history list is called a history event and is assigned a
number, beginning with 1 (one) when the shell starts up. The history
number that you may see in your prompt (see Prompt Expansion in zsh-
misc(1)) is the number that is to be assigned to the next command.
Overview
A history expansion begins with the first character of the histchars
parameter, which is ‘!’ by default, and may occur anywhere on the com-
mand line; history expansions do not nest. The ‘!’ can be escaped
with ‘\’ or can be enclosed between a pair of single quotes (’’) to
suppress its special meaning. Double quotes will not work for this.
Following this history character is an optional event designator (see
the section ‘Event Designators’) and then an optional word designator
(the section ‘Word Designators’); if neither of these designators is
present, no history expansion occurs.
Input lines containing history expansions are echoed after being
expanded, but before any other expansions take place and before the
command is executed. It is this expanded form that is recorded as the
history event for later references.
By default, a history reference with no event designator refers to the
same event as any preceding history reference on that command line; if
it is the only history reference in a command, it refers to the previ-
ous command. However, if the option CSH_JUNKIE_HISTORY is set, then
every history reference with no event specification always refers to
the previous command.
For example, ‘!’ is the event designator for the previous command, so
‘!!:1’ always refers to the first word of the previous command, and
‘!!$’ always refers to the last word of the previous command. With
CSH_JUNKIE_HISTORY set, then ‘!:1’ and ‘!$’ function in the same man-
ner as ‘!!:1’ and ‘!!$’, respectively. Conversely, if CSH_JUNKIE_HIS-
TORY is unset, then ‘!:1’ and ‘!$’ refer to the first and last words,
respectively, of the same event referenced by the nearest other his-
tory reference preceding them on the current command line, or to the
previous command if there is no preceding reference.
The character sequence ‘^foo^bar’ (where ‘^’ is actually the second
character of the histchars parameter) repeats the last command,
replacing the string foo with bar. More precisely, the sequence
‘^foo^bar^’ is synonymous with ‘!!:s^foo^bar^’, hence other modifiers
(see the section ‘Modifiers’) may follow the final ‘^’.
If the shell encounters the character sequence ‘!"’ in the input, the
history mechanism is temporarily disabled until the current list (see
zshmisc(1)) is fully parsed. The ‘!"’ is removed from the input, and
any subsequent ‘!’ characters have no special significance.
A less convenient but more comprehensible form of command history sup-
port is provided by the fc builtin.
Event Designators
An event designator is a reference to a command-line entry in the his-
tory list. In the list below, remember that the initial ‘!’ in each
item may be changed to another character by setting the histchars
parameter.
! Start a history expansion, except when followed by a blank,
newline, ‘=’ or ‘(’. If followed immediately by a word desig-
nator (see the section ‘Word Designators’), this forms a his-
tory reference with no event designator (see the section
‘Overview’).
!! Refer to the previous command. By itself, this expansion
repeats the previous command.
!n Refer to command-line n.
!-n Refer to the current command-line minus n.
!str Refer to the most recent command starting with str.
!?str[?]
Refer to the most recent command containing str. The trailing
‘?’ is necessary if this reference is to be followed by a
modifier or followed by any text that is not to be considered
part of str.
!# Refer to the current command line typed in so far. The line is
treated as if it were complete up to and including the word
before the one with the ‘!#’ reference.
!{...} Insulate a history reference from adjacent characters (if nec-
essary).
Word Designators
A word designator indicates which word or words of a given command
line are to be included in a history reference. A ‘:’ usually sepa-
rates the event specification from the word designator. It may be
omitted only if the word designator begins with a ‘^’, ‘$’, ‘*’, ‘-’
or ‘%’. Word designators include:
0 The first input word (command).
n The nth argument.
^ The first argument. That is, 1.
$ The last argument.
% The word matched by (the most recent) ?str search.
x-y A range of words; x defaults to 0.
* All the arguments, or a null value if there are none.
x* Abbreviates ‘x-$’.
x- Like ‘x*’ but omitting word $.
Note that a ‘%’ word designator works only when used in one of ‘!%’,
‘!:%’ or ‘!?str?:%’, and only when used after a !? expansion (possibly
in an earlier command). Anything else results in an error, although
the error may not be the most obvious one.
Modifiers
After the optional word designator, you can add a sequence of one or
more of the following modifiers, each preceded by a ‘:’. These modi-
fiers also work on the result of filename generation and parameter
expansion, except where noted.
h Remove a trailing pathname component, leaving the head. This
works like ‘dirname’.
r Remove a filename extension of the form ‘.xxx’, leaving the
root name.
e Remove all but the extension.
t Remove all leading pathname components, leaving the tail. This
works like ‘basename’.
p Print the new command but do not execute it. Only works with
history expansion.
q Quote the substituted words, escaping further substitutions.
Works with history expansion and parameter expansion, though
for parameters it is only useful if the resulting text is to be
re-evaluated such as by eval.
Q Remove one level of quotes from the substituted words.
x Like q, but break into words at whitespace. Does not work with
parameter expansion.
l Convert the words to all lowercase.
u Convert the words to all uppercase.
s/l/r[/]
Substitute r for l as described below. Unless preceded immedi-
ately by a g, with no colon between, the substitution is done
only for the first string that matches l. For arrays and for
filename generation, this applies to each word of the expanded
text.
& Repeat the previous s substitution. Like s, may be preceded
immediately by a g. In parameter expansion the & must appear
inside braces, and in filename generation it must be quoted
with a backslash.
The s/l/r/ substitution works as follows. The left-hand side of sub-
stitutions are not regular expressions, but character strings. Any
character can be used as the delimiter in place of ‘/’. A backslash
quotes the delimiter character. The character ‘&’, in the
right-hand-side r, is replaced by the text from the left-hand-side l.
The ‘&’ can be quoted with a backslash. A null l uses the previous
string either from the previous l or from the contextual scan string s
from ‘!?s’. You can omit the rightmost delimiter if a newline immedi-
ately follows r; the rightmost ‘?’ in a context scan can similarly be
omitted. Note the same record of the last l and r is maintained
across all forms of expansion.
The following f, F, w and W modifiers work only with parameter expan-
sion and filename generation. They are listed here to provide a sin-
gle point of reference for all modifiers.
f Repeats the immediately (without a colon) following modifier
until the resulting word doesn’t change any more.
F:expr:
Like f, but repeats only n times if the expression expr evalu-
ates to n. Any character can be used instead of the ‘:’; if
‘(’, ‘[’, or ‘{’ is used as the opening delimiter, the closing
delimiter should be ’)’, ‘]’, or ‘}’, respectively.
w Makes the immediately following modifier work on each word in
the string.
W:sep: Like w but words are considered to be the parts of the string
that are separated by sep. Any character can be used instead of
the ‘:’; opening parentheses are handled specially, see above.
PROCESS SUBSTITUTION
Each command argument of the form ‘<(list)’, ‘>(list)’ or ‘=(list)’ is
subject to process substitution. In the case of the < or > forms, the
shell runs process list asynchronously. If the system supports the
/dev/fd mechanism, the command argument is the name of the device file
corresponding to a file descriptor; otherwise, if the system supports
named pipes (FIFOs), the command argument will be a named pipe. If
the form with > is selected then writing on this special file will
provide input for list. If < is used, then the file passed as an
argument will be connected to the output of the list process. For
example,
paste <(cut -f1 file1) <(cut -f3 file2) |
tee >(process1) >(process2) >/dev/null
cuts fields 1 and 3 from the files file1 and file2 respectively,
pastes the results together, and sends it to the processes process1
and process2.
If =(...) is used instead of <(...), then the file passed as an argu-
ment will be the name of a temporary file containing the output of the
list process. This may be used instead of the < form for a program
that expects to lseek (see lseek(2)) on the input file.
The = form is useful as both the /dev/fd and the named pipe implemen-
tation of <(...) have drawbacks. In the former case, some programmes
may automatically close the file descriptor in question before examin-
ing the file on the command line, particularly if this is necessary
for security reasons such as when the programme is running setuid. In
the second case, if the programme does not actually open the file, the
subshell attempting to read from or write to the pipe will (in a typi-
cal implementation, different operating systems may have different
behaviour) block for ever and have to be killed explicitly. In both
cases, the shell actually supplies the information using a pipe, so
that programmes that expect to lseek (see lseek(2)) on the file will
not work.
Also note that the previous example can be more compactly and effi-
ciently written (provided the MULTIOS option is set) as:
paste <(cut -f1 file1) <(cut -f3 file2) \
> >(process1) > >(process2)
The shell uses pipes instead of FIFOs to implement the latter two pro-
cess substitutions in the above example.
There is an additional problem with >(process); when this is attached
to an external command, the parent shell does not wait for process to
finish and hence an immediately following command cannot rely on the
results being complete. The problem and solution are the same as
described in the section MULTIOS in zshmisc(1). Hence in a simplified
version of the example above:
paste <(cut -f1 file1) <(cut -f3 file2) > >(process)
(note that no MULTIOS are involved), process will be run asyn-
chronously. The workaround is:
{ paste <(cut -f1 file1) <(cut -f3 file2) } > >(process)
The extra processes here are spawned from the parent shell which will
wait for their completion.
PARAMETER EXPANSION
The character ‘$’ is used to introduce parameter expansions. See zsh-
param(1) for a description of parameters, including arrays, associa-
tive arrays, and subscript notation to access individual array ele-
ments.
Note in particular the fact that words of unquoted parameters are not
automatically split on whitespace unless the option SH_WORD_SPLIT is
set; see references to this option below for more details. This is an
important difference from other shells.
In the expansions discussed below that require a pattern, the form of
the pattern is the same as that used for filename generation; see the
section ‘Filename Generation’. Note that these patterns, along with
the replacement text of any substitutions, are themselves subject to
parameter expansion, command substitution, and arithmetic expansion.
In addition to the following operations, the colon modifiers described
in the section ‘Modifiers’ in the section ‘History Expansion’ can be
applied: for example, ${i:s/foo/bar/} performs string substitution on
the expansion of parameter $i.
${name}
The value, if any, of the parameter name is substituted. The
braces are required if the expansion is to be followed by a
letter, digit, or underscore that is not to be interpreted as
part of name. In addition, more complicated forms of substitu-
tion usually require the braces to be present; exceptions,
which only apply if the option KSH_ARRAYS is not set, are a
single subscript or any colon modifiers appearing after the
name, or any of the characters ‘^’, ‘=’, ‘~’, ‘#’ or ‘+’
appearing before the name, all of which work with or without
braces.
If name is an array parameter, and the KSH_ARRAYS option is not
set, then the value of each element of name is substituted, one
element per word. Otherwise, the expansion results in one word
only; with KSH_ARRAYS, this is the first element of an array.
No field splitting is done on the result unless the
SH_WORD_SPLIT option is set.
${+name}
If name is the name of a set parameter ‘1’ is substituted, oth-
erwise ‘0’ is substituted.
${name:-word}
If name is set and is non-null then substitute its value; oth-
erwise substitute word. If name is missing, substitute word.
${name:=word}
${name::=word}
In the first form, if name is unset or is null then set it to
word; in the second form, unconditionally set name to word. In
both forms, the value of the parameter is then substituted.
${name:?word}
If name is set and is non-null then substitute its value; oth-
erwise, print word and exit from the shell. Interactive shells
instead return to the prompt. If word is omitted, then a stan-
dard message is printed.
${name:+word}
If name is set and is non-null then substitute word; otherwise
substitute nothing.
If the colon is omitted from one of the above expressions containing a
colon, then the shell only checks whether name is set, not whether its
value is null.
In the following expressions, when name is an array and the substitu-
tion is not quoted, or if the ‘(@)’ flag or the name[@] syntax is
used, matching and replacement is performed on each array element sep-
arately.
${name#pattern}
${name##pattern}
If the pattern matches the beginning of the value of name, then
substitute the value of name with the matched portion deleted;
otherwise, just substitute the value of name. In the first
form, the smallest matching pattern is preferred; in the second
form, the largest matching pattern is preferred.
${name%pattern}
${name%%pattern}
If the pattern matches the end of the value of name, then sub-
stitute the value of name with the matched portion deleted;
otherwise, just substitute the value of name. In the first
form, the smallest matching pattern is preferred; in the second
form, the largest matching pattern is preferred.
${name:#pattern}
If the pattern matches the value of name, then substitute the
empty string; otherwise, just substitute the value of name. If
name is an array the matching array elements are removed (use
the ‘(M)’ flag to remove the non-matched elements).
${name/pattern/repl}
${name//pattern/repl}
Replace the longest possible match of pattern in the expansion
of parameter name by string repl. The first form replaces just
the first occurrence, the second form all occurrences. Both
pattern and repl are subject to double-quoted substitution, so
that expressions like ${name/$opat/$npat} will work, but note
the usual rule that pattern characters in $opat are not treated
specially unless either the option GLOB_SUBST is set, or $opat
is instead substituted as ${~opat}.
The pattern may begin with a ‘#’, in which case the pattern
must match at the start of the string, or ‘%’, in which case it
must match at the end of the string. The repl may be an empty
string, in which case the final ‘/’ may also be omitted. To
quote the final ‘/’ in other cases it should be preceded by a
single backslash; this is not necessary if the ‘/’ occurs
inside a substituted parameter. Note also that the ‘#’ and ‘%’
are not active if they occur inside a substituted parameter,
even at the start.
The first ‘/’ may be preceded by a ‘:’, in which case the match
will only succeed if it matches the entire word. Note also the
effect of the I and S parameter expansion flags below; however,
the flags M, R, B, E and N are not useful.
For example,
foo="twinkle twinkle little star" sub="t*e" rep="spy"
print ${foo//${~sub}/$rep}
print ${(S)foo//${~sub}/$rep}
Here, the ‘~’ ensures that the text of $sub is treated as a
pattern rather than a plain string. In the first case, the
longest match for t*e is substituted and the result is ‘spy
star’, while in the second case, the shortest matches are taken
and the result is ‘spy spy lispy star’.
${#spec}
If spec is one of the above substitutions, substitute the
length in characters of the result instead of the result
itself. If spec is an array expression, substitute the number
of elements of the result. Note that ‘^’, ‘=’, and ‘~’, below,
must appear to the left of ‘#’ when these forms are combined.
${^spec}
Turn on the RC_EXPAND_PARAM option for the evaluation of spec;
if the ‘^’ is doubled, turn it off. When this option is set,
array expansions of the form foo${xx}bar, where the parameter
xx is set to (a b c), are substituted with ‘fooabar foobbar
foocbar’ instead of the default ‘fooa b cbar’.
Internally, each such expansion is converted into the equiva-
lent list for brace expansion. E.g., ${^var} becomes
{$var[1],$var[2],...}, and is processed as described in the
section ‘Brace Expansion’ below. If word splitting is also in
effect the $var[N] may themselves be split into different list
elements.
${=spec}
Perform word splitting using the rules for SH_WORD_SPLIT during
the evaluation of spec, but regardless of whether the parameter
appears in double quotes; if the ‘=’ is doubled, turn it off.
This forces parameter expansions to be split into separate
words before substitution, using IFS as a delimiter. This is
done by default in most other shells.
Note that splitting is applied to word in the assignment forms
of spec before the assignment to name is performed. This
affects the result of array assignments with the A flag.
${~spec}
Turn on the GLOB_SUBST option for the evaluation of spec; if
the ‘~’ is doubled, turn it off. When this option is set, the
string resulting from the expansion will be interpreted as a
pattern anywhere that is possible, such as in filename expan-
sion and filename generation and pattern-matching contexts like
the right hand side of the ‘=’ and ‘!=’ operators in condi-
tions.
If a ${...} type parameter expression or a $(...) type command substi-
tution is used in place of name above, it is expanded first and the
result is used as if it were the value of name. Thus it is possible
to perform nested operations: ${${foo#head}%tail} substitutes the
value of $foo with both ‘head’ and ‘tail’ deleted. The form with
$(...) is often useful in combination with the flags described next;
see the examples below. Each name or nested ${...} in a parameter
expansion may also be followed by a subscript expression as described
in Array Parameters in zshparam(1).
Note that double quotes may appear around nested expressions, in which
case only the part inside is treated as quoted; for example,
${(f)"$(foo)"} quotes the result of $(foo), but the flag ‘(f)’ (see
below) is applied using the rules for unquoted expansions. Note fur-
ther that quotes are themselves nested in this context; for example,
in "${(@f)"$(foo)"}", there are two sets of quotes, one surrounding
the whole expression, the other (redundant) surrounding the $(foo) as
before.
Parameter Expansion Flags
If the opening brace is directly followed by an opening parenthesis,
the string up to the matching closing parenthesis will be taken as a
list of flags. In cases where repeating a flag is meaningful, the
repetitions need not be consecutive; for example, ‘(q%q%q)’ means the
same thing as the more readable ‘(%%qqq)’. The following flags are
supported:
% Expand all % escapes in the resulting words in the same way as
in in prompts (see the section ‘Prompt Expansion’). If this
flag is given twice, full prompt expansion is done on the
resulting words, depending on the setting of the PROMPT_PER-
CENT, PROMPT_SUBST and PROMPT_BANG options.
@ In double quotes, array elements are put into separate words.
E.g., ‘"${(@)foo}"’ is equivalent to ‘"${foo[@]}"’ and
‘"${(@)foo[1,2]}"’ is the same as ‘"$foo[1]" "$foo[2]"’. This
is distinct from field splitting by the the f, s or z flags,
which still applies within each array element.
A Create an array parameter with ‘${...=...}’, ‘${...:=...}’ or
‘${...::=...}’. If this flag is repeated (as in ‘AA’), create
an associative array parameter. Assignment is made before
sorting or padding. The name part may be a subscripted range
for ordinary arrays; the word part must be converted to an
array, for example by using ‘${(AA)=name=...}’ to activate
field splitting, when creating an associative array.
a With o or O, sort in array index order. Note that ‘oa’ is
therefore equivalent to the default but ‘Oa’ is useful for
obtaining an array’s elements in reverse order.
c With ${#name}, count the total number of characters in an
array, as if the elements were concatenated with spaces between
them.
C Capitalize the resulting words. ‘Words’ in this case refers to
sequences of alphanumeric characters separated by non-alphanu-
merics, not to words that result from field splitting.
e Perform parameter expansion, command substitution and arith-
metic expansion on the result. Such expansions can be nested
but too deep recursion may have unpredictable effects.
f Split the result of the expansion to lines. This is a shorthand
for ‘ps:\n:’.
F Join the words of arrays together using newline as a separator.
This is a shorthand for ‘pj:\n:’.
i With o or O, sort case-independently.
k If name refers to an associative array, substitute the keys
(element names) rather than the values of the elements. Used
with subscripts (including ordinary arrays), force indices or
keys to be substituted even if the subscript form refers to
values. However, this flag may not be combined with subscript
ranges.
L Convert all letters in the result to lower case.
n With o or O, sort numerically.
o Sort the resulting words in ascending order.
O Sort the resulting words in descending order.
P This forces the value of the parameter name to be interpreted
as a further parameter name, whose value will be used where
appropriate. If used with a nested parameter or command substi-
tution, the result of that will be taken as a parameter name in
the same way. For example, if you have ‘foo=bar’ and
‘bar=baz’, the strings ${(P)foo}, ${(P)${foo}}, and ${(P)$(echo
bar)} will be expanded to ‘baz’.
q Quote the resulting words with backslashes. If this flag is
given twice, the resulting words are quoted in single quotes
and if it is given three times, the words are quoted in double
quotes. If it is given four times, the words are quoted in sin-
gle quotes preceded by a $.
Q Remove one level of quotes from the resulting words.
t Use a string describing the type of the parameter where the
value of the parameter would usually appear. This string con-
sists of keywords separated by hyphens (‘-’). The first keyword
in the string describes the main type, it can be one of
‘scalar’, ‘array’, ‘integer’, ‘float’ or ‘association’. The
other keywords describe the type in more detail:
local for local parameters
left for left justified parameters
right_blanks
for right justified parameters with leading blanks
right_zeros
for right justified parameters with leading zeros
lower for parameters whose value is converted to all lower
case when it is expanded
upper for parameters whose value is converted to all upper
case when it is expanded
readonly
for readonly parameters
tag for tagged parameters
export for exported parameters
unique for arrays which keep only the first occurrence of
duplicated values
hide for parameters with the ‘hide’ flag
special
for special parameters defined by the shell
u Expand only the first occurrence of each unique word.
U Convert all letters in the result to upper case.
v Used with k, substitute (as two consecutive words) both the key
and the value of each associative array element. Used with
subscripts, force values to be substituted even if the sub-
script form refers to indices or keys.
V Make any special characters in the resulting words visible.
w With ${#name}, count words in arrays or strings; the s flag may
be used to set a word delimiter.
W Similar to w with the difference that empty words between
repeated delimiters are also counted.
X With this flag parsing errors occurring with the Q and e flags
or the pattern matching forms such as ‘${name#pattern}’ are
reported. Without the flag they are silently ignored.
z Split the result of the expansion into words using shell pars-
ing to find the words, i.e. taking into account any quoting in
the value.
Note that this is done very late, as for the ‘(s)’ flag. So to
access single words in the result, one has to use nested expan-
sions as in ‘${${(z)foo}[2]}’. Likewise, to remove the quotes
in the resulting words one would do: ‘${(Q)${(z)foo}}’.
The following flags (except p) are followed by one or more arguments
as shown. Any character, or the matching pairs ‘(...)’, ‘{...}’,
‘[...]’, or ‘<...>’, may be used in place of a colon as delimiters,
but note that when a flag takes more than one argument, a matched pair
of delimiters must surround each argument.
p Recognize the same escape sequences as the print builtin in
string arguments to any of the flags described below.
j:string:
Join the words of arrays together using string as a separator.
Note that this occurs before field splitting by the
SH_WORD_SPLIT option.
l:expr::string1::string2:
Pad the resulting words on the left. Each word will be trun-
cated if required and placed in a field expr characters wide.
The space to the left will be filled with string1 (concatenated
as often as needed) or spaces if string1 is not given. If both
string1 and string2 are given, this string is inserted once
directly to the left of each word, before padding.
r:expr::string1::string2:
As l, but pad the words on the right and insert string2 on the
right.
s:string:
Force field splitting (see the option SH_WORD_SPLIT) at the
separator string. Note that a string of two or more characters
means all must all match in sequence; this differs from the
treatment of two or more characters in the IFS parameter.
The following flags are meaningful with the ${...#...} or ${...%...}
forms. The S and I flags may also be used with the ${.../...} forms.
S Search substrings as well as beginnings or ends; with # start
from the beginning and with % start from the end of the string.
With substitution via ${.../...} or ${...//...}, specifies
non-greedy matching, i.e. that the shortest instead of the
longest match should be replaced.
I:expr:
Search the exprth match (where expr evaluates to a number).
This only applies when searching for substrings, either with
the S flag, or with ${.../...} (only the exprth match is sub-
stituted) or ${...//...} (all matches from the exprth on are
substituted). The default is to take the first match.
The exprth match is counted such that there is either one or
zero matches from each starting position in the string,
although for global substitution matches overlapping previous
replacements are ignored. With the ${...%...} and ${...%%...}
forms, the starting position for the match moves backwards from
the end as the index increases, while with the other forms it
moves forward from the start.
Hence with the string
which switch is the right switch for Ipswich?
substitutions of the form ${(SI:N:)string#w*ch} as N increases
from 1 will match and remove ‘which’, ‘witch’, ‘witch’ and
‘wich’; the form using ‘##’ will match and remove ‘which switch
is the right switch for Ipswich’, ‘witch is the right switch
for Ipswich’, ‘witch for Ipswich’ and ‘wich’. The form using
‘%’ will remove the same matches as for ‘#’, but in reverse
order, and the form using ‘%%’ will remove the same matches as
for ‘##’ in reverse order.
B Include the index of the beginning of the match in the result.
E Include the index of the end of the match in the result.
M Include the matched portion in the result.
N Include the length of the match in the result.
R Include the unmatched portion in the result (the Rest).
Rules
Here is a summary of the rules for substitution; this assumes that
braces are present around the substitution, i.e. ${...}. Some partic-
ular examples are given below. Note that the Zsh Development Group
accepts no responsibility for any brain damage which may occur during
the reading of the following rules.
1. Nested Substitution
If multiple nested ${...} forms are present, substitution is
performed from the inside outwards. At each level, the substi-
tution takes account of whether the current value is a scalar
or an array, whether the whole substitution is in double
quotes, and what flags are supplied to the current level of
substitution, just as if the nested substitution were the out-
ermost. The flags are not propagated up to enclosing substitu-
tions; the nested substitution will return either a scalar or
an array as determined by the flags, possibly adjusted for
quoting. All the following steps take place where applicable
at all levels of substitution. Note that, unless the ‘(P)’
flag is present, the flags and any subscripts apply directly to
the value of the nested substitution; for example, the expan-
sion ${${foo}} behaves exactly the same as ${foo}.
2. Parameter Subscripting
If the value is a raw parameter reference with a subscript,
such as ${var[3]}, the effect of subscripting is applied
directly to the parameter. Subscripts are evaluated left to
right; subsequent subscripts apply to the scalar or array value
yielded by the previous subscript. Thus if var is an array,
${var[1][2]} is the second character of the first word, but
${var[2,4][2]} is the entire third word (the second word of the
range of words two through four of the original array). Any
number of subscripts may appear.
3. Parameter Name Replacement
The effect of any (P) flag, which treats the value so far as a
parameter name and replaces it with the corresponding value, is
applied.
4. Double-Quoted Joining
If the value after this process is an array, and the substitu-
tion appears in double quotes, and no (@) flag is present at
the current level, the words of the value are joined with the
first character of the parameter $IFS, by default a space,
between each word (single word arrays are not modified). If
the (j) flag is present, that is used for joining instead of
$IFS.
5. Nested Subscripting
Any remaining subscripts (i.e. of a nested substitution) are
evaluated at this point, based on whether the value is an array
or a scalar. As with 2., multiple subscripts can appear. Note
that ${foo[2,4][2]} is thus equivalent to ${${foo[2,4]}[2]} and
also to "${${(@)foo[2,4]}[2]}" (the nested substitution returns
an array in both cases), but not to "${${foo[2,4]}[2]}" (the
nested substitution returns a scalar because of the quotes).
6. Modifiers
Any modifiers, as specified by a trailing ‘#’, ‘%’, ‘/’ (possi-
bly doubled) or by a set of modifiers of the form :... (see the
section ‘Modifiers’ in the section ‘History Expansion’), are
applied to the words of the value at this level.
7. Forced Joining
If the ‘(j)’ flag is present, or no ‘(j)’ flag is present but
the string is to be split as given by rules 8. or 9., and join-
ing did not take place at step 4., any words in the value are
joined together using the given string or the first character
of $IFS if none. Note that the ‘(F)’ flag implicitly supplies
a string for joining in this manner.
8. Forced Splitting
If one of the ‘(s)’, ‘(f)’ or ‘(z)’ flags are present, or the
‘=’ specifier was present (e.g. ${=var}), the word is split on
occurrences of the specified string, or (for = with neither of
the two flags present) any of the characters in $IFS.
9. Shell Word Splitting
If no ‘(s)’, ‘(f)’ or ‘=’ was given, but the word is not quoted
and the option SH_WORD_SPLIT is set, the word is split on
occurrences of any of the characters in $IFS. Note this step,
too, takes place at all levels of a nested substitution.
10. Re-Evaluation
Any ‘(e)’ flag is applied to the value, forcing it to be
re-examined for new parameter substitutions, but also for com-
mand and arithmetic substitutions.
11. Padding
Any padding of the value by the ‘(l.fill.)’ or ‘(r.fill.)’
flags is applied.
12. Semantic Joining
In contexts where expansion semantics requires a single word to
result, all words are rejoined with the first character of IFS
between. So in ‘${(P)${(f)lines}}’ the value of ${lines} is
split at newlines, but then must be joined again before the P
flag can be applied.
If a single word is not required, this rule is skipped.
Examples
The flag f is useful to split a double-quoted substitution line by
line. For example, ${(f)"$(<file)"} substitutes the contents of file
divided so that each line is an element of the resulting array. Com-
pare this with the effect of $(<file) alone, which divides the file up
by words, or the same inside double quotes, which makes the entire
content of the file a single string.
The following illustrates the rules for nested parameter expansions.
Suppose that $foo contains the array (bar baz):
"${(@)${foo}[1]}"
This produces the result b. First, the inner substitution
"${foo}", which has no array (@) flag, produces a single word
result "bar baz". The outer substitution "${(@)...[1]}"
detects that this is a scalar, so that (despite the ‘(@)’ flag)
the subscript picks the first character.
"${${(@)foo}[1]}"
This produces the result ‘bar’. In this case, the inner sub-
stitution "${(@)foo}" produces the array ‘(bar baz)’. The
outer substitution "${...[1]}" detects that this is an array
and picks the first word. This is similar to the simple case
"${foo[1]}".
As an example of the rules for word splitting and joining, suppose
$foo contains the array ‘(ax1 bx1)’. Then
${(s/x/)foo}
produces the words ‘a’, ‘1 b’ and ‘1’.
${(j/x/s/x/)foo}
produces ‘a’, ‘1’, ‘b’ and ‘1’.
${(s/x/)foo%%1*}
produces ‘a’ and ‘ b’ (note the extra space). As substitution
occurs before either joining or splitting, the operation first
generates the modified array (ax bx), which is joined to give
"ax bx", and then split to give ‘a’, ‘ b’ and ‘’. The final
empty string will then be elided, as it is not in double
quotes.
COMMAND SUBSTITUTION
A command enclosed in parentheses preceded by a dollar sign, like
‘$(...)’, or quoted with grave accents, like ‘‘...‘’, is replaced with
its standard output, with any trailing newlines deleted. If the sub-
stitution is not enclosed in double quotes, the output is broken into
words using the IFS parameter. The substitution ‘$(cat foo)’ may be
replaced by the equivalent but faster ‘$(<foo)’. In either case, if
the option GLOB_SUBST is set, the output is eligible for filename gen-
eration.
ARITHMETIC EXPANSION
A string of the form ‘$[exp]’ or ‘$((exp))’ is substituted with the
value of the arithmetic expression exp. exp is subjected to parameter
expansion, command substitution and arithmetic expansion before it is
evaluated. See the section ‘Arithmetic Evaluation’.
BRACE EXPANSION
A string of the form ‘foo{xx,yy,zz}bar’ is expanded to the individual
words ‘fooxxbar’, ‘fooyybar’ and ‘foozzbar’. Left-to-right order is
preserved. This construct may be nested. Commas may be quoted in
order to include them literally in a word.
An expression of the form ‘{n1..n2}’, where n1 and n2 are integers, is
expanded to every number between n1 and n2 inclusive. If either num-
ber begins with a zero, all the resulting numbers will be padded with
leading zeroes to that minimum width. If the numbers are in decreas-
ing order the resulting sequence will also be in decreasing order.
If a brace expression matches none of the above forms, it is left
unchanged, unless the BRACE_CCL option is set. In that case, it is
expanded to a sorted list of the individual characters between the
braces, in the manner of a search set. ‘-’ is treated specially as in
a search set, but ‘^’ or ‘!’ as the first character is treated nor-
mally.
Note that brace expansion is not part of filename generation (glob-
bing); an expression such as */{foo,bar} is split into two separate
words */foo and */bar before filename generation takes place. In par-
ticular, note that this is liable to produce a ‘no match’ error if
either of the two expressions does not match; this is to be contrasted
with */(foo|bar), which is treated as a single pattern but otherwise
has similar effects.
FILENAME EXPANSION
Each word is checked to see if it begins with an unquoted ‘~’. If it
does, then the word up to a ‘/’, or the end of the word if there is no
‘/’, is checked to see if it can be substituted in one of the ways
described here. If so, then the ‘~’ and the checked portion are
replaced with the appropriate substitute value.
A ‘~’ by itself is replaced by the value of $HOME. A ‘~’ followed by
a ‘+’ or a ‘-’ is replaced by the value of $PWD or $OLDPWD, respec-
tively.
A ‘~’ followed by a number is replaced by the directory at that posi-
tion in the directory stack. ‘~0’ is equivalent to ‘~+’, and ‘~1’ is
the top of the stack. ‘~+’ followed by a number is replaced by the
directory at that position in the directory stack. ‘~+0’ is equiva-
lent to ‘~+’, and ‘~+1’ is the top of the stack. ‘~-’ followed by a
number is replaced by the directory that many positions from the bot-
tom of the stack. ‘~-0’ is the bottom of the stack. The PUSHD_MINUS
option exchanges the effects of ‘~+’ and ‘~-’ where they are followed
by a number.
A ‘~’ followed by anything not already covered is looked up as a named
directory, and replaced by the value of that named directory if found.
Named directories are typically home directories for users on the sys-
tem. They may also be defined if the text after the ‘~’ is the name
of a string shell parameter whose value begins with a ‘/’. It is also
possible to define directory names using the -d option to the hash
builtin.
In certain circumstances (in prompts, for instance), when the shell
prints a path, the path is checked to see if it has a named directory
as its prefix. If so, then the prefix portion is replaced with a ‘~’
followed by the name of the directory. The shortest way of referring
to the directory is used, with ties broken in favour of using a named
directory, except when the directory is / itself. The parameters $PWD
and $OLDPWD are never abbreviated in this fashion.
If a word begins with an unquoted ‘=’ and the EQUALS option is set,
the remainder of the word is taken as the name of a command. If a
command exists by that name, the word is replaced by the full pathname
of the command.
Filename expansion is performed on the right hand side of a parameter
assignment, including those appearing after commands of the typeset
family. In this case, the right hand side will be treated as a
colon-separated list in the manner of the PATH parameter, so that a
‘~’ or an ‘=’ following a ‘:’ is eligible for expansion. All such
behaviour can be disabled by quoting the ‘~’, the ‘=’, or the whole
expression (but not simply the colon); the EQUALS option is also
respected.
If the option MAGIC_EQUAL_SUBST is set, any unquoted shell argument in
the form ‘identifier=expression’ becomes eligible for file expansion
as described in the previous paragraph. Quoting the first ‘=’ also
inhibits this.
FILENAME GENERATION
If a word contains an unquoted instance of one of the characters ‘*’,
‘(’, ‘|’, ‘<’, ‘[’, or ‘?’, it is regarded as a pattern for filename
generation, unless the GLOB option is unset. If the EXTENDED_GLOB
option is set, the ‘^’ and ‘#’ characters also denote a pattern; oth-
erwise they are not treated specially by the shell.
The word is replaced with a list of sorted filenames that match the
pattern. If no matching pattern is found, the shell gives an error
message, unless the NULL_GLOB option is set, in which case the word is
deleted; or unless the NOMATCH option is unset, in which case the word
is left unchanged.
In filename generation, the character ‘/’ must be matched explicitly;
also, a ‘.’ must be matched explicitly at the beginning of a pattern
or after a ‘/’, unless the GLOB_DOTS option is set. No filename gen-
eration pattern matches the files ‘.’ or ‘..’. In other instances of
pattern matching, the ‘/’ and ‘.’ are not treated specially.
Glob Operators
* Matches any string, including the null string.
? Matches any character.
[...] Matches any of the enclosed characters. Ranges of characters
can be specified by separating two characters by a ‘-’. A ‘-’
or ‘]’ may be matched by including it as the first character in
the list. There are also several named classes of characters,
in the form ‘[:name:]’ with the following meanings:
‘[:alnum:]’ alphanumeric, ‘[:alpha:]’ alphabetic, ‘[:ascii:]’
7-bit, ‘[:blank:]’ space or tab, ‘[:cntrl:]’ control character,
‘[:digit:]’ decimal digit, ‘[:graph:]’ printable character
except whitespace, ‘[:lower:]’ lowercase letter, ‘[:print:]’
printable character, ‘[:punct:]’ printable character neither
alphanumeric nor whitespace, ‘[:space:]’ whitespace character,
‘[:upper:]’ uppercase letter, ‘[:xdigit:]’ hexadecimal digit.
These use the macros provided by the operating system to test
for the given character combinations, including any modifica-
tions due to local language settings: see ctype(3). Note that
the square brackets are additional to those enclosing the whole
set of characters, so to test for a single alphanumeric charac-
ter you need ‘[[:alnum:]]’. Named character sets can be used
alongside other types, e.g. ‘[[:alpha:]0-9]’.
[^...]
[!...] Like [...], except that it matches any character which is not
in the given set.
<[x]-[y]>
Matches any number in the range x to y, inclusive. Either of
the numbers may be omitted to make the range open-ended; hence
‘<->’ matches any number. To match individual digits, the
[...] form is more efficient.
Be careful when using other wildcards adjacent to patterns of
this form; for example, <0-9>* will actually match any number
whatsoever at the start of the string, since the ‘<0-9>’ will
match the first digit, and the ‘*’ will match any others. This
is a trap for the unwary, but is in fact an inevitable conse-
quence of the rule that the longest possible match always suc-
ceeds. Expressions such as ‘<0-9>[^[:digit:]]*’ can be used
instead.
(...) Matches the enclosed pattern. This is used for grouping. If
the KSH_GLOB option is set, then a ‘@’, ‘*’, ‘+’, ‘?’ or ‘!’
immediately preceding the ‘(’ is treated specially, as detailed
below. The option SH_GLOB prevents bare parentheses from being
used in this way, though the KSH_GLOB option is still avail-
able.
Note that grouping cannot extend over multiple directories: it
is an error to have a ‘/’ within a group (this only applies for
patterns used in filename generation). There is one exception:
a group of the form (pat/)# appearing as a complete path seg-
ment can match a sequence of directories. For example,
foo/(a*/)#bar matches foo/bar, foo/any/bar,
foo/any/anyother/bar, and so on.
x|y Matches either x or y. This operator has lower precedence than
any other. The ‘|’ character must be within parentheses, to
avoid interpretation as a pipeline.
^x (Requires EXTENDED_GLOB to be set.) Matches anything except
the pattern x. This has a higher precedence than ‘/’, so
‘^foo/bar’ will search directories in ‘.’ except ‘./foo’ for a
file named ‘bar’.
x~y (Requires EXTENDED_GLOB to be set.) Match anything that
matches the pattern x but does not match y. This has lower
precedence than any operator except ‘|’, so ‘*/*~foo/bar’ will
search for all files in all directories in ‘.’ and then
exclude ‘foo/bar’ if there was such a match. Multiple patterns
can be excluded by ‘foo~bar~baz’. In the exclusion pattern
(y), ‘/’ and ‘.’ are not treated specially the way they usually
are in globbing.
x# (Requires EXTENDED_GLOB to be set.) Matches zero or more
occurrences of the pattern x. This operator has high
precedence; ‘12#’ is equivalent to ‘1(2#)’, rather than
‘(12)#’. It is an error for an unquoted ‘#’ to follow some-
thing which cannot be repeated; this includes an empty string,
a pattern already followed by ‘##’, or parentheses when part of
a KSH_GLOB pattern (for example, ‘!(foo)#’ is invalid and must
be replaced by ‘*(!(foo))’).
x## (Requires EXTENDED_GLOB to be set.) Matches one or more occur-
rences of the pattern x. This operator has high precedence;
‘12##’ is equivalent to ‘1(2##)’, rather than ‘(12)##’. No
more than two active ‘#’ characters may appear together.
ksh-like Glob Operators
If the KSH_GLOB option is set, the effects of parentheses can be modi-
fied by a preceding ‘@’, ‘*’, ‘+’, ‘?’ or ‘!’. This character need
not be unquoted to have special effects, but the ‘(’ must be.
@(...) Match the pattern in the parentheses. (Like ‘(...)’.)
*(...) Match any number of occurrences. (Like ‘(...)#’.)
+(...) Match at least one occurrence. (Like ‘(...)##’.)
?(...) Match zero or one occurrence. (Like ‘(|...)’.)
!(...) Match anything but the expression in parentheses. (Like
‘(^(...))’.)
Precedence
The precedence of the operators given above is (highest) ‘^’, ‘/’,
‘~’, ‘|’ (lowest); the remaining operators are simply treated from
left to right as part of a string, with ‘#’ and ‘##’ applying to the
shortest possible preceding unit (i.e. a character, ‘?’, ‘[...]’,
‘<...>’, or a parenthesised expression). As mentioned above, a ‘/’
used as a directory separator may not appear inside parentheses, while
a ‘|’ must do so; in patterns used in other contexts than filename
generation (for example, in case statements and tests within
‘[[...]]’), a ‘/’ is not special; and ‘/’ is also not special after a
‘~’ appearing outside parentheses in a filename pattern.
Globbing Flags
There are various flags which affect any text to their right up to the
end of the enclosing group or to the end of the pattern; they require
the EXTENDED_GLOB option. All take the form (#X) where X may have one
of the following forms:
i Case insensitive: upper or lower case characters in the pat-
tern match upper or lower case characters.
l Lower case characters in the pattern match upper or lower case
characters; upper case characters in the pattern still only
match upper case characters.
I Case sensitive: locally negates the effect of i or l from that
point on.
b Activate backreferences for parenthesised groups in the pat-
tern; this does not work in filename generation. When a pat-
tern with a set of active parentheses is matched, the strings
matched by the groups are stored in the array $match, the
indices of the beginning of the matched parentheses in the
array $mbegin, and the indices of the end in the array $mend,
with the first element of each array corresponding to the first
parenthesised group, and so on. These arrays are not otherwise
special to the shell. The indices use the same convention as
does parameter substitution, so that elements of $mend and
$mbegin may be used in subscripts; the KSH_ARRAYS option is
respected. Sets of globbing flags are not considered parenthe-
sised groups; only the first nine active parentheses can be
referenced.
For example,
foo="a string with a message"
if [[ $foo = (a|an)’ ’(#b)(*)’ ’* ]]; then
print ${foo[$mbegin[1],$mend[1]]}
fi
prints ‘string with a’. Note that the first parenthesis is
before the (#b) and does not create a backreference.
Backreferences work with all forms of pattern matching other
than filename generation, but note that when performing matches
on an entire array, such as ${array#pattern}, or a global sub-
stitution, such as ${param//pat/repl}, only the data for the
last match remains available. In the case of global replace-
ments this may still be useful. See the example for the m flag
below.
The numbering of backreferences strictly follows the order of
the opening parentheses from left to right in the pattern
string, although sets of parentheses may be nested. There are
special rules for parentheses followed by ‘#’ or ‘##’. Only
the last match of the parenthesis is remembered: for example,
in ‘[[ abab = (#b)([ab])# ]]’, only the final ‘b’ is stored in
match[1]. Thus extra parentheses may be necessary to match the
complete segment: for example, use ‘X((ab|cd)#)Y’ to match a
whole string of either ‘ab’ or ‘cd’ between ‘X’ and ‘Y’, using
the value of $match[1] rather than $match[2].
If the match fails none of the parameters is altered, so in
some cases it may be necessary to initialise them beforehand.
If some of the backreferences fail to match --- which happens
if they are in an alternate branch which fails to match, or if
they are followed by # and matched zero times --- then the
matched string is set to the empty string, and the start and
end indices are set to -1.
Pattern matching with backreferences is slightly slower than
without.
B Deactivate backreferences, negating the effect of the b flag
from that point on.
m Set references to the match data for the entire string matched;
this is similar to backreferencing and does not work in file-
name generation. The flag must be in effect at the end of the
pattern, i.e. not local to a group. The parameters $MATCH,
$MBEGIN and $MEND will be set to the string matched and to the
indices of the beginning and end of the string, respectively.
This is most useful in parameter substitutions, as otherwise
the string matched is obvious.
For example,
arr=(veldt jynx grimps waqf zho buck)
print ${arr//(#m)[aeiou]/${(U)MATCH}}
forces all the matches (i.e. all vowels) into uppercase, print-
ing ‘vEldt jynx grImps wAqf zhO bUck’.
Unlike backreferences, there is no speed penalty for using
match references, other than the extra substitutions required
for the replacement strings in cases such as the example shown.
M Deactivate the m flag, hence no references to match data will
be created.
anum Approximate matching: num errors are allowed in the string
matched by the pattern. The rules for this are described in
the next subsection.
s, e Unlike the other flags, these have only a local effect, and
each must appear on its own: ‘(#s)’ and ‘(#e)’ are the only
valid forms. The ‘(#s)’ flag succeeds only at the start of the
test string, and the ‘(#e)’ flag succeeds only at the end of
the test string; they correspond to ‘^’ and ‘$’ in standard
regular expressions. They are useful for matching path seg-
ments in patterns other than those in filename generation
(where path segments are in any case treated separately). For
example, ‘*((#s)|/)test((#e)|/)*’ matches a path segment ‘test’
in any of the following strings: test, test/at/start,
at/end/test, in/test/middle.
Another use is in parameter substitution; for example
‘${array/(#s)A*Z(#e)}’ will remove only elements of an array
which match the complete pattern ‘A*Z’. There are other ways
of performing many operations of this type, however the combi-
nation of the substitution operations ‘/’ and ‘//’ with the
‘(#s)’ and ‘(#e)’ flags provides a single simple and memorable
method.
Note that assertions of the form ‘(^(#s))’ also work, i.e.
match anywhere except at the start of the string, although this
actually means ‘anything except a zero-length portion at the
start of the string’; you need to use ‘(""~(#s))’ to match a
zero-length portion of the string not at the start.
q A ‘q’ and everything up to the closing parenthesis of the glob-
bing flags are ignored by the pattern matching code. This is
intended to support the use of glob qualifiers, see below. The
result is that the pattern ‘(#b)(*).c(#q.)’ can be used both
for globbing and for matching against a string. In the former
case, the ‘(#q.)’ will be treated as a glob qualifier and the
‘(#b)’ will not be useful, while in the latter case the ‘(#b)’
is useful for backreferences and the ‘(#q.)’ will be ignored.
Note that colon modifiers in the glob qualifiers are also not
applied in ordinary pattern matching.
For example, the test string fooxx can be matched by the pattern
(#i)FOOXX, but not by (#l)FOOXX, (#i)FOO(#I)XX or ((#i)FOOX)X. The
string (#ia2)readme specifies case-insensitive matching of readme with
up to two errors.
When using the ksh syntax for grouping both KSH_GLOB and EXTENDED_GLOB
must be set and the left parenthesis should be preceded by @. Note
also that the flags do not affect letters inside [...] groups, in
other words (#i)[a-z] still matches only lowercase letters. Finally,
note that when examining whole paths case-insensitively every direc-
tory must be searched for all files which match, so that a pattern of
the form (#i)/foo/bar/... is potentially slow.
Approximate Matching
When matching approximately, the shell keeps a count of the errors
found, which cannot exceed the number specified in the (#anum) flags.
Four types of error are recognised:
1. Different characters, as in fooxbar and fooybar.
2. Transposition of characters, as in banana and abnana.
3. A character missing in the target string, as with the pattern
road and target string rod.
4. An extra character appearing in the target string, as with
stove and strove.
Thus, the pattern (#a3)abcd matches dcba, with the errors occurring by
using the first rule twice and the second once, grouping the string as
[d][cb][a] and [a][bc][d].
Non-literal parts of the pattern must match exactly, including charac-
ters in character ranges: hence (#a1)??? matches strings of length
four, by applying rule 4 to an empty part of the pattern, but not
strings of length two, since all the ? must match. Other characters
which must match exactly are initial dots in filenames (unless the
GLOB_DOTS option is set), and all slashes in filenames, so that a/bc
is two errors from ab/c (the slash cannot be transposed with another
character). Similarly, errors are counted separately for non-contigu-
ous strings in the pattern, so that (ab|cd)ef is two errors from aebf.
When using exclusion via the ~ operator, approximate matching is
treated entirely separately for the excluded part and must be acti-
vated separately. Thus, (#a1)README~READ_ME matches READ.ME but not
READ_ME, as the trailing READ_ME is matched without approximation.
However, (#a1)README~(#a1)READ_ME does not match any pattern of the
form READ?ME as all such forms are now excluded.
Apart from exclusions, there is only one overall error count; however,
the maximum errors allowed may be altered locally, and this can be
delimited by grouping. For example, (#a1)cat((#a0)dog)fox allows one
error in total, which may not occur in the dog section, and the pat-
tern (#a1)cat(#a0)dog(#a1)fox is equivalent. Note that the point at
which an error is first found is the crucial one for establishing
whether to use approximation; for example, (#a1)abc(#a0)xyz will not
match abcdxyz, because the error occurs at the ‘x’, where approxima-
tion is turned off.
Entire path segments may be matched approximately, so that
‘(#a1)/foo/d/is/available/at/the/bar’ allows one error in any path
segment. This is much less efficient than without the (#a1), however,
since every directory in the path must be scanned for a possible
approximate match. It is best to place the (#a1) after any path seg-
ments which are known to be correct.
Recursive Globbing
A pathname component of the form ‘(foo/)#’ matches a path consisting
of zero or more directories matching the pattern foo.
As a shorthand, ‘**/’ is equivalent to ‘(*/)#’; note that this there-
fore matches files in the current directory as well as subdirectories.
Thus:
ls (*/)#bar
or
ls **/bar
does a recursive directory search for files named ‘bar’ (potentially
including the file ‘bar’ in the current directory). This form does
not follow symbolic links; the alternative form ‘***/’ does, but is
otherwise identical. Neither of these can be combined with other
forms of globbing within the same path segment; in that case, the ‘*’
operators revert to their usual effect.
Glob Qualifiers
Patterns used for filename generation may end in a list of qualifiers
enclosed in parentheses. The qualifiers specify which filenames that
otherwise match the given pattern will be inserted in the argument
list.
If the option BARE_GLOB_QUAL is set, then a trailing set of parenthe-
ses containing no ‘|’ or ‘(’ characters (or ‘~’ if it is special) is
taken as a set of glob qualifiers. A glob subexpression that would
normally be taken as glob qualifiers, for example ‘(^x)’, can be
forced to be treated as part of the glob pattern by doubling the
parentheses, in this case producing ‘((^x))’.
If the option EXTENDED_GLOB is set, a different syntax for glob quali-
fiers is available, namely ‘(#qx)’ where x is any of the same glob
qualifiers used in the other format. The qualifiers must still appear
at the end of the pattern. However, with this syntax multiple glob
qualifiers may be chained together. They are treated as a logical AND
of the individual sets of flags. Also, as the syntax is unambiguous,
the expression will be treated as glob qualifiers just as long any
parentheses contained within it are balanced; appearance of ‘|’, ‘(’
or ‘~’ does not negate the effect. Note that qualifiers will be
recognised in this form even if a bare glob qualifier exists at the
end of the pattern, for example ‘*(#q*)(.)’ will recognise executable
regular files if both options are set; however, mixed syntax should
probably be avoided for the sake of clarity.
A qualifier may be any one of the following:
/ directories
. plain files
@ symbolic links
= sockets
p named pipes (FIFOs)
* executable plain files (0100)
% device files (character or block special)
%b block special files
%c character special files
r owner-readable files (0400)
w owner-writable files (0200)
x owner-executable files (0100)
A group-readable files (0040)
I group-writable files (0020)
E group-executable files (0010)
R world-readable files (0004)
W world-writable files (0002)
X world-executable files (0001)
s setuid files (04000)
S setgid files (02000)
t files with the sticky bit (01000)
fspec files with access rights matching spec. This spec may be a
octal number optionally preceded by a ‘=’, a ‘+’, or a ‘-’. If
none of these characters is given, the behavior is the same as
for ‘=’. The octal number describes the mode bits to be
expected, if combined with a ‘=’, the value given must match
the file-modes exactly, with a ‘+’, at least the bits in the
given number must be set in the file-modes, and with a ‘-’, the
bits in the number must not be set. Giving a ‘?’ instead of a
octal digit anywhere in the number ensures that the correspond-
ing bits in the file-modes are not checked, this is only useful
in combination with ‘=’.
If the qualifier ‘f’ is followed by any other character
anything up to the next matching character (‘[’, ‘{’, and ‘<’
match ‘]’, ‘}’, and ‘>’ respectively, any other character
matches itself) is taken as a list of comma-separated
sub-specs. Each sub-spec may be either an octal number as
described above or a list of any of the characters ‘u’, ‘g’,
‘o’, and ‘a’, followed by a ‘=’, a ‘+’, or a ‘-’, followed by a
list of any of the characters ‘r’, ‘w’, ‘x’, ‘s’, and ‘t’, or
an octal digit. The first list of characters specify which
access rights are to be checked. If a ‘u’ is given, those for
the owner of the file are used, if a ‘g’ is given, those of the
group are checked, a ‘o’ means to test those of other users,
and the ‘a’ says to test all three groups. The ‘=’, ‘+’, and
‘-’ again says how the modes are to be checked and have the
same meaning as described for the first form above. The second
list of characters finally says which access rights are to be
expected: ‘r’ for read access, ‘w’ for write access, ‘x’ for
the right to execute the file (or to search a directory), ‘s’
for the setuid and setgid bits, and ‘t’ for the sticky bit.
Thus, ‘*(f70?)’ gives the files for which the owner has read,
write, and execute permission, and for which other group mem-
bers have no rights, independent of the permissions for other
users. The pattern ‘*(f-100)’ gives all files for which the
owner does not have execute permission, and ‘*(f:gu+w,o-rx:)’
gives the files for which the owner and the other members of
the group have at least write permission, and for which other
users don’t have read or execute permission.
estring
The string will be executed as shell code. The filename will
be included in the list if and only if the code returns a zero
status (usually the status of the last command). The first
character after the ‘e’ will be used as a separator and any-
thing up to the next matching separator will be taken as the
string; ‘[’, ‘{’, and ‘<’ match ‘]’, ‘}’, and ‘>’, respec-
tively, while any other character matches itself. Note that
expansions must be quoted in the string to prevent them from
being expanded before globbing is done.
During the execution of string the filename currently being
tested is available in the parameter REPLY; the parameter may
be altered to a string to be inserted into the list instead of
the original filename. In addition, the parameter reply may be
set to an array or a string, which overrides the value of
REPLY. If set to an array, the latter is inserted into the
command line word by word.
For example, suppose a directory contains a single file
‘lonely’. Then the expression ‘*(e:’reply=(${REPLY}{1,2})’:)’
will cause the words ‘lonely1 lonely2’ to be inserted into the
command line. Note the quotation marks.
ddev files on the device dev
l[-|+]ct
files having a link count less than ct (-), greater than ct
(+), or equal to ct
U files owned by the effective user ID
G files owned by the effective group ID
uid files owned by user ID id if it is a number, if not, than the
character after the ‘u’ will be used as a separator and the
string between it and the next matching separator (‘[’, ‘{’,
and ‘<’ match ‘]’, ‘}’, and ‘>’ respectively, any other charac-
ter matches itself) will be taken as a user name, and the user
ID of this user will be taken (e.g. ‘u:foo:’ or ‘u[foo]’ for
user ‘foo’)
gid like uid but with group IDs or names
a[Mwhms][-|+]n
files accessed exactly n days ago. Files accessed within the
last n days are selected using a negative value for n (-n).
Files accessed more than n days ago are selected by a positive
n value (+n). Optional unit specifiers ‘M’, ‘w’, ‘h’, ‘m’ or
‘s’ (e.g. ‘ah5’) cause the check to be performed with months
(of 30 days), weeks, hours, minutes or seconds instead of days,
respectively. For instance, ‘echo *(ah-5)’ would echo files
accessed within the last five hours.
m[Mwhms][-|+]n
like the file access qualifier, except that it uses the file
modification time.
c[Mwhms][-|+]n
like the file access qualifier, except that it uses the file
inode change time.
L[+|-]n
files less than n bytes (-), more than n bytes (+), or exactly
n bytes in length. If this flag is directly followed by a ‘k’
(‘K’), ‘m’ (‘M’), or ‘p’ (‘P’) (e.g. ‘Lk-50’) the check is per-
formed with kilobytes, megabytes, or blocks (of 512 bytes)
instead.
^ negates all qualifiers following it
- toggles between making the qualifiers work on symbolic links
(the default) and the files they point to
M sets the MARK_DIRS option for the current pattern
T appends a trailing qualifier mark to the filenames, analogous
to the LIST_TYPES option, for the current pattern (overrides M)
N sets the NULL_GLOB option for the current pattern
D sets the GLOB_DOTS option for the current pattern
n sets the NUMERIC_GLOB_SORT option for the current pattern
oc specifies how the names of the files should be sorted. If c is
n they are sorted by name (the default); if it is L they are
sorted depending on the size (length) of the files; if l they
are sorted by the number of links; if a, m, or c they are
sorted by the time of the last access, modification, or inode
change respectively; if d, files in subdirectories appear
before those in the current directory at each level of the
search --- this is best combined with other criteria, for exam-
ple ‘odon’ to sort on names for files within the same direc-
tory. Note that a, m, and c compare the age against the cur-
rent time, hence the first name in the list is the youngest
file. Also note that the modifiers ^ and - are used, so
‘*(^-oL)’ gives a list of all files sorted by file size in
descending order, following any symbolic links.
Oc like ‘o’, but sorts in descending order; i.e. ‘*(^oc)’ is the
same as ‘*(Oc)’ and ‘*(^Oc)’ is the same as ‘*(oc)’; ‘Od’ puts
files in the current directory before those in subdirectories
at each level of the search.
[beg[,end]]
specifies which of the matched filenames should be included in
the returned list. The syntax is the same as for array sub-
scripts. beg and the optional end may be mathematical expres-
sions. As in parameter subscripting they may be negative to
make them count from the last match backward. E.g.:
‘*(-OL[1,3])’ gives a list of the names of the three largest
files.
More than one of these lists can be combined, separated by commas. The
whole list matches if at least one of the sublists matches (they are
‘or’ed, the qualifiers in the sublists are ‘and’ed). Some qualifiers,
however, affect all matches generated, independent of the sublist in
which they are given. These are the qualifiers ‘M’, ‘T’, ‘N’, ‘D’,
‘n’, ‘o’, ‘O’ and the subscripts given in brackets (‘[...]’).
If a ‘:’ appears in a qualifier list, the remainder of the expression
in parenthesis is interpreted as a modifier (see the section ‘Modi-
fiers’ in the section ‘History Expansion’). Note that each modifier
must be introduced by a separate ‘:’. Note also that the result after
modification does not have to be an existing file. The name of any
existing file can be followed by a modifier of the form ‘(:..)’ even
if no actual filename generation is performed. Thus:
ls *(-/)
lists all directories and symbolic links that point to directories,
and
ls *(%W)
lists all world-writable device files in the current directory, and
ls *(W,X)
lists all files in the current directory that are world-writable or
world-executable, and
echo /tmp/foo*(u0^@:t)
outputs the basename of all root-owned files beginning with the string
‘foo’ in /tmp, ignoring symlinks, and
ls *.*~(lex|parse).[ch](^D^l1)
lists all files having a link count of one whose names contain a dot
(but not those starting with a dot, since GLOB_DOTS is explicitly
switched off) except for lex.c, lex.h, parse.c and parse.h.
print b*.pro(#q:s/pro/shmo/)(#q.:s/builtin/shmiltin/)
demonstrates how colon modifiers and other qualifiers may be chained
together. The ordinary qualifier ‘.’ is applied first, then the colon
modifiers in order from left to right. So if EXTENDED_GLOB is set and
the base pattern matches the regular file builtin.pro, the shell will
ZSHPARAM(1) ZSHPARAM(1)
print ‘shmiltin.shmo’.
NAME
zshparam - zsh parameters
DESCRIPTION
A parameter has a name, a value, and a number of attributes. A name
may be any sequence of alphanumeric characters and underscores, or the
single characters ‘*’, ‘@’, ‘#’, ‘?’, ‘-’, ‘$’, or ‘!’. The value may
be a scalar (a string), an integer, an array (indexed numerically), or
an associative array (an unordered set of name-value pairs, indexed by
name). To declare the type of a parameter, or to assign a scalar or
integer value to a parameter, use the typeset builtin.
The value of a scalar or integer parameter may also be assigned by
writing:
name=value
If the integer attribute, -i, is set for name, the value is subject to
arithmetic evaluation. Furthermore, by replacing ‘=’ with ‘+=’, a
parameter can be added or appended to. See the section ‘Array Parame-
ters’ for additional forms of assignment.
To refer to the value of a parameter, write ‘$name’ or ‘${name}’. See
Parameter Expansion in zshexpn(1) for complete details.
In the parameter lists that follow, the mark ‘<S>’ indicates that the
parameter is special. Special parameters cannot have their type
changed or their readonly attribute turned off, and if a special
parameter is unset, then later recreated, the special properties will
be retained. ‘<Z>’ indicates that the parameter does not exist when
the shell initializes in sh or ksh emulation mode.
ARRAY PARAMETERS
To assign an array value, write one of:
set -A name value ...
name=(value ...)
If no parameter name exists, an ordinary array parameter is created.
If the parameter name exists and is a scalar, it is replaced by a new
array. Ordinary array parameters may also be explicitly declared
with:
typeset -a name
Associative arrays must be declared before assignment, by using:
typeset -A name
When name refers to an associative array, the list in an assignment is
interpreted as alternating keys and values:
set -A name key value ...
name=(key value ...)
Every key must have a value in this case. Note that this assigns to
the entire array, deleting any elements that do not appear in the
list.
To create an empty array (including associative arrays), use one of:
set -A name
name=()
Array Subscripts
Individual elements of an array may be selected using a subscript. A
subscript of the form ‘[exp]’ selects the single element exp, where
exp is an arithmetic expression which will be subject to arithmetic
expansion as if it were surrounded by ‘$((...))’. The elements are
numbered beginning with 1, unless the KSH_ARRAYS option is set in
which case they are numbered from zero.
Subscripts may be used inside braces used to delimit a parameter name,
thus ‘${foo[2]}’ is equivalent to ‘$foo[2]’. If the KSH_ARRAYS option
is set, the braced form is the only one that works, as bracketed
expressions otherwise are not treated as subscripts.
The same subscripting syntax is used for associative arrays, except
that no arithmetic expansion is applied to exp. However, the parsing
rules for arithmetic expressions still apply, which affects the way
that certain special characters must be protected from interpretation.
See Subscript Parsing below for details.
A subscript of the form ‘[*]’ or ‘[@]’ evaluates to all elements of an
array; there is no difference between the two except when they appear
within double quotes. ‘"$foo[*]"’ evaluates to ‘"$foo[1] $foo[2]
..."’, whereas ‘"$foo[@]"’ evaluates to ‘"$foo[1]" "$foo[2]" ...’.
For associative arrays, ‘[*]’ or ‘[@]’ evaluate to all the values, in
no particular order. Note that this does not substitute the keys; see
the documentation for the ‘k’ flag under Parameter Expansion Flags in
zshexpn(1) for complete details. When an array parameter is refer-
enced as ‘$name’ (with no subscript) it evaluates to ‘$name[*]’,
unless the KSH_ARRAYS option is set in which case it evaluates to
‘${name[0]}’ (for an associative array, this means the value of the
key ‘0’, which may not exist even if there are values for other keys).
A subscript of the form ‘[exp1,exp2]’ selects all elements in the
range exp1 to exp2, inclusive. (Associative arrays are unordered, and
so do not support ranges.) If one of the subscripts evaluates to a
negative number, say -n, then the nth element from the end of the
array is used. Thus ‘$foo[-3]’ is the third element from the end of
the array foo, and ‘$foo[1,-1]’ is the same as ‘$foo[*]’.
Subscripting may also be performed on non-array values, in which case
the subscripts specify a substring to be extracted. For example, if
FOO is set to ‘foobar’, then ‘echo $FOO[2,5]’ prints ‘ooba’.
Array Element Assignment
A subscript may be used on the left side of an assignment like so:
name[exp]=value
In this form of assignment the element or range specified by exp is
replaced by the expression on the right side. An array (but not an
associative array) may be created by assignment to a range or element.
Arrays do not nest, so assigning a parenthesized list of values to an
element or range changes the number of elements in the array, shifting
the other elements to accommodate the new values. (This is not sup-
ported for associative arrays.)
This syntax also works as an argument to the typeset command:
typeset "name[exp]"=value
The value may not be a parenthesized list in this case; only sin-
gle-element assignments may be made with typeset. Note that quotes
are necessary in this case to prevent the brackets from being inter-
preted as filename generation operators. The noglob precommand modi-
fier could be used instead.
To delete an element of an ordinary array, assign ‘()’ to that ele-
ment. To delete an element of an associative array, use the unset
command:
unset "name[exp]"
Subscript Flags
If the opening bracket, or the comma in a range, in any subscript
expression is directly followed by an opening parenthesis, the string
up to the matching closing one is considered to be a list of flags, as
in ‘name[(flags)exp]’. The flags currently understood are:
w If the parameter subscripted is a scalar than this flag makes
subscripting work on words instead of characters. The default
word separator is whitespace.
s:string:
This gives the string that separates words (for use with the w
flag).
p Recognize the same escape sequences as the print builtin in the
string argument of a subsequent ‘s’ flag.
f If the parameter subscripted is a scalar than this flag makes
subscripting work on lines instead of characters, i.e. with
elements separated by newlines. This is a shorthand for
‘pws:\n:’.
r Reverse subscripting: if this flag is given, the exp is taken
as a pattern and the result is the first matching array
element, substring or word (if the parameter is an array, if it
is a scalar, or if it is a scalar and the ‘w’ flag is given,
respectively). The subscript used is the number of the match-
ing element, so that pairs of subscripts such as
‘$foo[(r)??,3]’ and ‘$foo[(r)??,(r)f*]’ are possible. If the
parameter is an associative array, only the value part of each
pair is compared to the pattern, and the result is that value.
Reverse subscripts may be used for assigning to ordinary array
elements, but not for assigning to associative arrays.
R Like ‘r’, but gives the last match. For associative arrays,
gives all possible matches.
i Like ‘r’, but gives the index of the match instead; this may
not be combined with a second argument. On the left side of an
assignment, behaves like ‘r’. For associative arrays, the key
part of each pair is compared to the pattern, and the first
matching key found is the result.
I Like ‘i’, but gives the index of the last match, or all possi-
ble matching keys in an associative array.
k If used in a subscript on an associative array, this flag
causes the keys to be interpreted as patterns, and returns the
value for the first key found where exp is matched by the key.
This flag does not work on the left side of an assignment to an
associative array element. If used on another type of parame-
ter, this behaves like ‘r’.
K On an associative array this is like ‘k’ but returns all values
where exp is matched by the keys. On other types of parameters
this has the same effect as ‘R’.
n:expr:
If combined with ‘r’, ‘R’, ‘i’ or ‘I’, makes them give the nth
or nth last match (if expr evaluates to n). This flag is
ignored when the array is associative.
b:expr:
If combined with ‘r’, ‘R’, ‘i’ or ‘I’, makes them begin at the
nth or nth last element, word, or character (if expr evaluates
to n). This flag is ignored when the array is associative.
e This flag has no effect and for ordinary arrays is retained for
backward compatibility only. For associative arrays, this flag
can be used to force * or @ to be interpreted as a single key
rather than as a reference to all values. This flag may be
used on the left side of an assignment.
See Parameter Expansion Flags (zshexpn(1)) for additional ways to
manipulate the results of array subscripting.
Subscript Parsing
This discussion applies mainly to associative array key strings and to
patterns used for reverse subscripting (the ‘r’, ‘R’, ‘i’, etc.
flags), but it may also affect parameter substitutions that appear as
part of an arithmetic expression in an ordinary subscript.
It is possible to avoid the use of subscripts in assignments to asso-
ciative array elements by using the syntax:
aa+=(’key with "*strange*" characters’ ’value string’)
This adds a new key/value pair if the key is not already present, and
replaces the value for the existing key if it is.
The basic rule to remember when writing a subscript expression is that
all text between the opening ‘[’ and the closing ‘]’ is interpreted as
if it were in double quotes (see zshmisc(1)). However, unlike double
quotes which normally cannot nest, subscript expressions may appear
inside double-quoted strings or inside other subscript expressions (or
both!), so the rules have two important differences.
The first difference is that brackets (‘[’ and ‘]’) must appear as
balanced pairs in a subscript expression unless they are preceded by a
backslash (‘\’). Therefore, within a subscript expression (and unlike
true double-quoting) the sequence ‘\[’ becomes ‘[’, and similarly ‘\]’
becomes ‘]’. This applies even in cases where a backslash is not nor-
mally required; for example, the pattern ‘[^[]’ (to match any charac-
ter other than an open bracket) should be written ‘[^\[]’ in a
reverse-subscript pattern. However, note that ‘\[^\[\]’ and even
‘\[^[]’ mean the same thing, because backslashes are always stripped
when they appear before brackets!
The same rule applies to parentheses (‘(’ and ‘)’) and braces (‘{’ and
‘}’): they must appear either in balanced pairs or preceded by a back-
slash, and backslashes that protect parentheses or braces are removed
during parsing. This is because parameter expansions may be
surrounded balanced braces, and subscript flags are introduced by bal-
anced parenthesis.
The second difference is that a double-quote (‘"’) may appear as part
of a subscript expression without being preceded by a backslash, and
therefore that the two characters ‘\"’ remain as two characters in the
subscript (in true double-quoting, ‘\"’ becomes ‘"’). However,
because of the standard shell quoting rules, any double-quotes that
appear must occur in balanced pairs unless preceded by a backslash.
This makes it more difficult to write a subscript expression that con-
tains an odd number of double-quote characters, but the reason for
this difference is so that when a subscript expression appears inside
true double-quotes, one can still write ‘\"’ (rather than ‘\\\"’) for
‘"’.
To use an odd number of double quotes as a key in an assignment, use
the typeset builtin and an enclosing pair of double quotes; to refer
to the value of that key, again use double quotes:
typeset -A aa
typeset "aa[one\"two\"three\"quotes]"=QQQ
print "$aa[one\"two\"three\"quotes]"
It is important to note that the quoting rules do not change when a
parameter expansion with a subscript is nested inside another sub-
script expression. That is, it is not necessary to use additional
backslashes within the inner subscript expression; they are removed
only once, from the innermost subscript outwards. Parameters are also
expanded from the innermost subscript first, as each expansion is
encountered left to right in the outer expression.
A further complication arises from a way in which subscript parsing is
not different from double quote parsing. As in true double-quoting,
the sequences ‘\*’, and ‘\@’ remain as two characters when they appear
in a subscript expression. To use a literal ‘*’ or ‘@’ as an associa-
tive array key, the ‘e’ flag must be used:
typeset -A aa
aa[(e)*]=star
print $aa[(e)*]
A last detail must be considered when reverse subscripting is per-
formed. Parameters appearing in the subscript expression are first
expanded and then the complete expression is interpreted as a pattern.
This has two effects: first, parameters behave as if GLOB_SUBST were
on (and it cannot be turned off); second, backslashes are interpreted
twice, once when parsing the array subscript and again when parsing
the pattern. In a reverse subscript, it’s necessary to use four back-
slashes to cause a single backslash to match literally in the pattern.
For complex patterns, it is often easiest to assign the desired pat-
tern to a parameter and then refer to that parameter in the subscript,
because then the backslashes, brackets, parentheses, etc., are seen
only when the complete expression is converted to a pattern. To match
the value of a parameter literally in a reverse subscript, rather than
as a pattern, use ‘${(q)name}’ (see zshexpn(1)) to quote the expanded
value.
Note that the ‘k’ and ‘K’ flags are reverse subscripting for an ordi-
nary array, but are not reverse subscripting for an associative array!
(For an associative array, the keys in the array itself are inter-
preted as patterns by those flags; the subscript is a plain string in
that case.)
One final note, not directly related to subscripting: the numeric
names of positional parameters (described below) are parsed specially,
so for example ‘$2foo’ is equivalent to ‘${2}foo’. Therefore, to use
subscript syntax to extract a substring from a positional parameter,
the expansion must be surrounded by braces; for example, ‘${2[3,5]}’
evaluates to the third through fifth characters of the second posi-
tional parameter, but ‘$2[3,5]’ is the entire second parameter con-
catenated with the filename generation pattern ‘[3,5]’.
POSITIONAL PARAMETERS
The positional parameters provide access to the command-line arguments
of a shell function, shell script, or the shell itself; see the sec-
tion ‘Invocation’, and also the section ‘Functions’. The parameter n,
where n is a number, is the nth positional parameter. The parameters
*, @ and argv are arrays containing all the positional parameters;
thus ‘$argv[n]’, etc., is equivalent to simply ‘$n’.
Positional parameters may be changed after the shell or function
starts by using the set builtin, by assigning to the argv array, or by
direct assignment of the form ‘n=value’ where n is the number of the
positional parameter to be changed. This also creates (with empty
values) any of the positions from 1 to n that do not already have val-
ues. Note that, because the positional parameters form an array, an
array assignment of the form ‘n=(value ...)’ is allowed, and has the
effect of shifting all the values at positions greater than n by as
many positions as necessary to accommodate the new values.
LOCAL PARAMETERS
Shell function executions delimit scopes for shell parameters.
(Parameters are dynamically scoped.) The typeset builtin, and its
alternative forms declare, integer, local and readonly (but not
export), can be used to declare a parameter as being local to the
innermost scope.
When a parameter is read or assigned to, the innermost existing param-
eter of that name is used. (That is, the local parameter hides any
less-local parameter.) However, assigning to a non-existent parame-
ter, or declaring a new parameter with export, causes it to be created
in the outermost scope.
Local parameters disappear when their scope ends. unset can be used
to delete a parameter while it is still in scope; any outer parameter
of the same name remains hidden.
Special parameters may also be made local; they retain their special
attributes unless either the existing or the newly-created parameter
has the -h (hide) attribute. This may have unexpected effects: there
is no default value, so if there is no assignment at the point the
variable is made local, it will be set to an empty value (or zero in
the case of integers). The following:
typeset PATH=/new/directory:$PATH
is valid for temporarily allowing the shell or programmes called from
it to find the programs in /new/directory inside a function.
Note that the restriction in older versions of zsh that local parame-
ters were never exported has been removed.
PARAMETERS SET BY THE SHELL
The following parameters are automatically set by the shell:
! <S> The process ID of the last background command invoked.
# <S> The number of positional parameters in decimal. Note that some
confusion may occur with the syntax $#param which substitutes
the length of param. Use ${#} to resolve ambiguities. In par-
ticular, the sequence ‘$#-...’ in an arithmetic expression is
interpreted as the length of the parameter -, q.v.
ARGC <S> <Z>
Same as #.
$ <S> The process ID of this shell.
- <S> Flags supplied to the shell on invocation or by the set or
setopt commands.
* <S> An array containing the positional parameters.
argv <S> <Z>
Same as *. Assigning to argv changes the local positional
parameters, but argv is not itself a local parameter. Deleting
argv with unset in any function deletes it everywhere, although
only the innermost positional parameter array is deleted (so *
and @ in other scopes are not affected).
@ <S> Same as argv[@], even when argv is not set.
? <S> The exit value returned by the last command.
0 <S> The name used to invoke the current shell. If the FUNC-
TION_ARGZERO option is set, this is set temporarily within a
shell function to the name of the function, and within a
sourced script to the name of the script.
status <S> <Z>
Same as ?.
pipestatus <S> <Z>
An array containing the exit values returned by all commands in
the last pipeline.
_ <S> The last argument of the previous command. Also, this parame-
ter is set in the environment of every command executed to the
full pathname of the command.
CPUTYPE
The machine type (microprocessor class or machine model), as
determined at run time.
EGID <S>
The effective group ID of the shell process. If you have suf-
ficient privileges, you may change the effective group ID of
the shell process by assigning to this parameter. Also (assum-
ing sufficient privileges), you may start a single command with
a different effective group ID by ‘(EGID=gid; command)’
EUID <S>
The effective user ID of the shell process. If you have suffi-
cient privileges, you may change the effective user ID of the
shell process by assigning to this parameter. Also (assuming
sufficient privileges), you may start a single command with a
different effective user ID by ‘(EUID=uid; command)’
ERRNO <S>
The value of errno (see errno(3)) as set by the most recently
failed system call. This value is system dependent and is
intended for debugging purposes. It is also useful with the
zsh/system module which allows the number to be turned into a
name or message.
GID <S>
The real group ID of the shell process. If you have sufficient
privileges, you may change the group ID of the shell process by
assigning to this parameter. Also (assuming sufficient privi-
leges), you may start a single command under a different group
ID by ‘(GID=gid; command)’
HOST The current hostname.
LINENO <S>
The line number of the current line within the current script,
sourced file, or shell function being executed, whichever was
started most recently. Note that in the case of shell func-
tions the line number refers to the function as it appeared in
the original definition, not necessarily as displayed by the
functions builtin.
LOGNAME
If the corresponding variable is not set in the environment of
the shell, it is initialized to the login name corresponding to
the current login session. This parameter is exported by
default but this can be disabled using the typeset builtin.
MACHTYPE
The machine type (microprocessor class or machine model), as
determined at compile time.
OLDPWD The previous working directory. This is set when the shell
initializes and whenever the directory changes.
OPTARG <S>
The value of the last option argument processed by the getopts
command.
OPTIND <S>
The index of the last option argument processed by the getopts
command.
OSTYPE The operating system, as determined at compile time.
PPID <S>
The process ID of the parent of the shell.
PWD The present working directory. This is set when the shell ini-
tializes and whenever the directory changes.
RANDOM <S>
A pseudo-random integer from 0 to 32767, newly generated each
time this parameter is referenced. The random number generator
can be seeded by assigning a numeric value to RANDOM.
The values of RANDOM form an intentionally-repeatable
pseudo-random sequence; subshells that reference RANDOM will
result in identical pseudo-random values unless the value of
RANDOM is referenced or seeded in the parent shell in between
subshell invocations.
SECONDS <S>
The number of seconds since shell invocation. If this parame-
ter is assigned a value, then the value returned upon reference
will be the value that was assigned plus the number of seconds
since the assignment.
Unlike other special parameters, the type of the SECONDS param-
eter can be changed using the typeset command. Only integer
and one of the floating point types are allowed. For example,
‘typeset -F SECONDS’ causes the value to be reported as a
floating point number. The precision is six decimal places,
although not all places may be useful.
SHLVL <S>
Incremented by one each time a new shell is started.
signals
An array containing the names of the signals.
TTY The name of the tty associated with the shell, if any.
TTYIDLE <S>
The idle time of the tty associated with the shell in seconds
or -1 if there is no such tty.
UID <S>
The real user ID of the shell process. If you have sufficient
privileges, you may change the user ID of the shell by assign-
ing to this parameter. Also (assuming sufficient privileges),
you may start a single command under a different user ID by
‘(UID=uid; command)’
USERNAME <S>
The username corresponding to the real user ID of the shell
process. If you have sufficient privileges, you may change the
username (and also the user ID and group ID) of the shell by
assigning to this parameter. Also (assuming sufficient privi-
leges), you may start a single command under a different user-
name (and user ID and group ID) by ‘(USERNAME=username; com-
mand)’
VENDOR The vendor, as determined at compile time.
ZSH_NAME
Expands to the basename of the command used to invoke this
instance of zsh.
ZSH_VERSION
The version number of this zsh.
PARAMETERS USED BY THE SHELL
The following parameters are used by the shell.
In cases where there are two parameters with an upper- and lowercase
form of the same name, such as path and PATH, the lowercase form is an
array and the uppercase form is a scalar with the elements of the
array joined together by colons. These are similar to tied parameters
created via ‘typeset -T’. The normal use for the colon-separated form
is for exporting to the environment, while the array form is easier to
manipulate within the shell. Note that unsetting either of the pair
will unset the other; they retain their special properties when recre-
ated, and recreating one of the pair will recreate the other.
ARGV0 If exported, its value is used as the argv[0] of external com-
mands. Usually used in constructs like ‘ARGV0=emacs nethack’.
BAUD The baud rate of the current connection. Used by the line edi-
tor update mechanism to compensate for a slow terminal by
delaying updates until necessary. This may be profitably set
to a lower value in some circumstances, e.g. for slow modems
dialing into a communications server which is connected to a
host via a fast link; in this case, this variable would be set
by default to the speed of the fast link, and not the modem.
This parameter should be set to the baud rate of the slowest
part of the link for best performance. The compensation mecha-
nism can be turned off by setting the variable to zero.
cdpath <S> <Z> (CDPATH <S>)
An array (colon-separated list) of directories specifying the
search path for the cd command.
COLUMNS <S>
The number of columns for this terminal session. Used for
printing select lists and for the line editor.
DIRSTACKSIZE
The maximum size of the directory stack. If the stack gets
larger than this, it will be truncated automatically. This is
useful with the AUTO_PUSHD option.
ENV If the ENV environment variable is set when zsh is invoked as
sh or ksh, $ENV is sourced after the profile scripts. The
value of ENV is subjected to parameter expansion, command sub-
stitution, and arithmetic expansion before being interpreted as
a pathname. Note that ENV is not used unless zsh is emulating
sh or ksh.
FCEDIT The default editor for the fc builtin.
fignore <S> <Z> (FIGNORE <S>)
An array (colon separated list) containing the suffixes of
files to be ignored during filename completion. However, if
completion only generates files with suffixes in this list,
then these files are completed anyway.
fpath <S> <Z> (FPATH <S>)
An array (colon separated list) of directories specifying the
search path for function definitions. This path is searched
when a function with the -u attribute is referenced. If an
executable file is found, then it is read and executed in the
current environment.
histchars <S>
Three characters used by the shell’s history and lexical analy-
sis mechanism. The first character signals the start of a his-
tory expansion (default ‘!’). The second character signals the
start of a quick history substitution (default ‘^’). The third
character is the comment character (default ‘#’).
HISTCHARS <S> <Z>
Same as histchars. (Deprecated.)
HISTFILE
The file to save the history in when an interactive shell
exits. If unset, the history is not saved.
HISTSIZE <S>
The maximum number of events stored in the internal history
list. If you use the HIST_EXPIRE_DUPS_FIRST option, setting
this value larger than the SAVEHIST size will give you the dif-
ference as a cushion for saving duplicated history events.
HOME <S>
The default argument for the cd command.
IFS <S>
Internal field separators (by default space, tab, newline and
NUL), that are used to separate words which result from command
or parameter expansion and words read by the read builtin. Any
characters from the set space, tab and newline that appear in
the IFS are called IFS white space. One or more IFS white
space characters or one non-IFS white space character together
with any adjacent IFS white space character delimit a field.
If an IFS white space character appears twice consecutively in
the IFS, this character is treated as if it were not an IFS
white space character.
KEYTIMEOUT
The time the shell waits, in hundredths of seconds, for another
key to be pressed when reading bound multi-character sequences.
LANG <S>
This variable determines the locale category for any category
not specifically selected via a variable starting with ‘LC_’.
LC_ALL <S>
This variable overrides the value of the ‘LANG’ variable and
the value of any of the other variables starting with ‘LC_’.
LC_COLLATE <S>
This variable determines the locale category for character col-
lation information within ranges in glob brackets and for sort-
ing.
LC_CTYPE <S>
This variable determines the locale category for character han-
dling functions.
LC_MESSAGES <S>
This variable determines the language in which messages should
be written. Note that zsh does not use message catalogs.
LC_NUMERIC <S>
This variable affects the decimal point character and thousands
separator character for the formatted input/output functions
and string conversion functions. Note that zsh ignores this
setting when parsing floating point mathematical expressions.
LC_TIME <S>
This variable determines the locale category for date and time
formatting in prompt escape sequences.
LINES <S>
The number of lines for this terminal session. Used for print-
ing select lists and for the line editor.
LISTMAX
In the line editor, the number of matches to list without ask-
ing first. If the value is negative, the list will be shown if
it spans at most as many lines as given by the absolute value.
If set to zero, the shell asks only if the top of the listing
would scroll off the screen.
LOGCHECK
The interval in seconds between checks for login/logout activ-
ity using the watch parameter.
MAIL If this parameter is set and mailpath is not set, the shell
looks for mail in the specified file.
MAILCHECK
The interval in seconds between checks for new mail.
mailpath <S> <Z> (MAILPATH <S>)
An array (colon-separated list) of filenames to check for new
mail. Each filename can be followed by a ‘?’ and a message
that will be printed. The message will undergo parameter
expansion, command substitution and arithmetic expansion with
the variable $_ defined as the name of the file that has
changed. The default message is ‘You have new mail’. If an
element is a directory instead of a file the shell will recur-
sively check every file in every subdirectory of the element.
manpath <S> <Z> (MANPATH <S> <Z>)
An array (colon-separated list) whose value is not used by the
shell. The manpath array can be useful, however, since setting
it also sets MANPATH, and vice versa.
module_path <S> <Z> (MODULE_PATH <S>)
An array (colon-separated list) of directories that zmodload
searches for dynamically loadable modules. This is initialized
to a standard pathname, usually ‘/usr/local/lib/zsh/$ZSH_VER-
SION’. (The ‘/usr/local/lib’ part varies from installation to
installation.) For security reasons, any value set in the
environment when the shell is started will be ignored.
These parameters only exist if the installation supports
dynamic module loading.
NULLCMD <S>
The command name to assume if a redirection is specified with
no command. Defaults to cat. For sh/ksh behavior, change this
to :. For csh-like behavior, unset this parameter; the shell
will print an error message if null commands are entered.
path <S> <Z> (PATH <S>)
An array (colon-separated list) of directories to search for
commands. When this parameter is set, each directory is
scanned and all files found are put in a hash table.
POSTEDIT <S>
This string is output whenever the line editor exits. It usu-
ally contains termcap strings to reset the terminal.
PROMPT <S> <Z>
PROMPT2 <S> <Z>
PROMPT3 <S> <Z>
PROMPT4 <S> <Z>
Same as PS1, PS2, PS3 and PS4, respectively.
prompt <S> <Z>
Same as PS1.
PS1 <S>
The primary prompt string, printed before a command is read.
the default is ‘%m%# ’. It undergoes a special form of expan-
sion before being displayed; see the section ‘Prompt Expan-
sion’.
PS2 <S>
The secondary prompt, printed when the shell needs more infor-
mation to complete a command. It is expanded in the same way
as PS1. The default is ‘%_> ’, which displays any shell con-
structs or quotation marks which are currently being processed.
PS3 <S>
Selection prompt used within a select loop. It is expanded in
the same way as PS1. The default is ‘?# ’.
PS4 <S>
The execution trace prompt. Default is ‘+%N:%i> ’, which dis-
plays the name of the current shell structure and the line num-
ber within it. In sh or ksh emulation, the default is ‘+ ’.
psvar <S> <Z> (PSVAR <S>)
An array (colon-separated list) whose first nine values can be
used in PROMPT strings. Setting psvar also sets PSVAR, and
vice versa.
READNULLCMD <S>
The command name to assume if a single input redirection is
specified with no command. Defaults to more.
REPORTTIME
If nonnegative, commands whose combined user and system execu-
tion times (measured in seconds) are greater than this value
have timing statistics printed for them.
REPLY This parameter is reserved by convention to pass string values
between shell scripts and shell builtins in situations where a
function call or redirection are impossible or undesirable.
The read builtin and the select complex command may set REPLY,
and filename generation both sets and examines its value when
evaluating certain expressions. Some modules also employ REPLY
for similar purposes.
reply As REPLY, but for array values rather than strings.
RPROMPT <S>
RPS1 <S>
This prompt is displayed on the right-hand side of the screen
when the primary prompt is being displayed on the left. This
does not work if the SINGLELINEZLE option is set. It is
expanded in the same way as PS1.
RPROMPT2 <S>
RPS2 <S>
This prompt is displayed on the right-hand side of the screen
when the secondary prompt is being displayed on the left. This
does not work if the SINGLELINEZLE option is set. It is
expanded in the same way as PS2.
SAVEHIST
The maximum number of history events to save in the history
file.
SPROMPT <S>
The prompt used for spelling correction. The sequence ‘%R’
expands to the string which presumably needs spelling correc-
tion, and ‘%r’ expands to the proposed correction. All other
prompt escapes are also allowed.
STTY If this parameter is set in a command’s environment, the shell
runs the stty command with the value of this parameter as argu-
ments in order to set up the terminal before executing the com-
mand. The modes apply only to the command, and are reset when
it finishes or is suspended. If the command is suspended and
continued later with the fg or wait builtins it will see the
modes specified by STTY, as if it were not suspended. This
(intentionally) does not apply if the command is continued via
‘kill -CONT’. STTY is ignored if the command is run in the
background, or if it is in the environment of the shell but not
explicitly assigned to in the input line. This avoids running
stty at every external command by accidentally exporting it.
Also note that STTY should not be used for window size specifi-
cations; these will not be local to the command.
TERM <S>
The type of terminal in use. This is used when looking up
termcap sequences. An assignment to TERM causes zsh to re-ini-
tialize the terminal, even if the value does not change (e.g.,
‘TERM=$TERM’). It is necessary to make such an assignment upon
any change to the terminal definition database or terminal type
in order for the new settings to take effect.
TIMEFMT
The format of process time reports with the time keyword. The
default is ‘%E real %U user %S system %P %J’. Recognizes
the following escape sequences:
%% A ‘%’.
%U CPU seconds spent in user mode.
%S CPU seconds spent in kernel mode.
%E Elapsed time in seconds.
%P The CPU percentage, computed as (%U+%S)/%E.
%J The name of this job.
A star may be inserted between the percent sign and flags
printing time. This cause the time to be printed in
‘hh:mm:ss.ttt’ format (hours and minutes are only printed if
they are not zero).
TMOUT If this parameter is nonzero, the shell will receive an ALRM
signal if a command is not entered within the specified number
of seconds after issuing a prompt. If there is a trap on
SIGALRM, it will be executed and a new alarm is scheduled using
the value of the TMOUT parameter after executing the trap. If
no trap is set, and the idle time of the terminal is not less
than the value of the TMOUT parameter, zsh terminates. Other-
wise a new alarm is scheduled to TMOUT seconds after the last
keypress.
TMPPREFIX
A pathname prefix which the shell will use for all temporary
files. Note that this should include an initial part for the
file name as well as any directory names. The default is
‘/tmp/zsh’.
watch <S> <Z> (WATCH <S>)
An array (colon-separated list) of login/logout events to
report. If it contains the single word ‘all’, then all
login/logout events are reported. If it contains the single
word ‘notme’, then all events are reported as with ‘all’ except
$USERNAME. An entry in this list may consist of a username, an
‘@’ followed by a remote hostname, and a ‘%’ followed by a line
(tty). Any or all of these components may be present in an
entry; if a login/logout event matches all of them, it is
reported.
WATCHFMT
The format of login/logout reports if the watch parameter is
set. Default is ‘%n has %a %l from %m’. Recognizes the fol-
lowing escape sequences:
%n The name of the user that logged in/out.
%a The observed action, i.e. "logged on" or "logged off".
%l The line (tty) the user is logged in on.
%M The full hostname of the remote host.
%m The hostname up to the first ‘.’. If only the IP
address is available or the utmp field contains the name
of an X-windows display, the whole name is printed.
NOTE: The ‘%m’ and ‘%M’ escapes will work only if there
is a host name field in the utmp on your machine. Oth-
erwise they are treated as ordinary strings.
%S (%s)
Start (stop) standout mode.
%U (%u)
Start (stop) underline mode.
%B (%b)
Start (stop) boldface mode.
%t
%@ The time, in 12-hour, am/pm format.
%T The time, in 24-hour format.
%w The date in ‘day-dd’ format.
%W The date in ‘mm/dd/yy’ format.
%D The date in ‘yy-mm-dd’ format.
%(x:true-text:false-text)
Specifies a ternary expression. The character following
the x is arbitrary; the same character is used to sepa-
rate the text for the "true" result from that for the
"false" result. Both the separator and the right paren-
thesis may be escaped with a backslash. Ternary expres-
sions may be nested.
The test character x may be any one of ‘l’, ‘n’, ‘m’ or
‘M’, which indicate a ‘true’ result if the corresponding
escape sequence would return a non-empty value; or it
may be ‘a’, which indicates a ‘true’ result if the
watched user has logged in, or ‘false’ if he has logged
out. Other characters evaluate to neither true nor
false; the entire expression is omitted in this case.
If the result is ‘true’, then the true-text is formatted
according to the rules above and printed, and the
false-text is skipped. If ‘false’, the true-text is
skipped and the false-text is formatted and printed.
Either or both of the branches may be empty, but both
separators must be present in any case.
WORDCHARS <S>
A list of non-alphanumeric characters considered part of a word
by the line editor.
ZBEEP If set, this gives a string of characters, which can use all
the same codes as the bindkey command as described in the
zsh/zle module entry in zshmodules(1), that will be output to
the terminal instead of beeping. This may have a visible
instead of an audible effect; for example, the string
‘\e[?5h\e[?5l’ on a vt100 or xterm will have the effect of
flashing reverse video on and off (if you usually use reverse
video, you should use the string ‘\e[?5l\e[?5h’ instead). This
takes precedence over the NOBEEP option.
ZDOTDIR
The directory to search for shell startup files (.zshrc, etc),
ZSHOPTIONS(1) ZSHOPTIONS(1)
if not $HOME.
NAME
zshoptions - zsh options
SPECIFYING OPTIONS
Options are primarily referred to by name. These names are case
insensitive and underscores are ignored. For example, ‘allexport’ is
equivalent to ‘A__lleXP_ort’.
The sense of an option name may be inverted by preceding it with ‘no’,
so ‘setopt No_Beep’ is equivalent to ‘unsetopt beep’. This inversion
can only be done once, so ‘nonobeep’ is not a synonym for ‘beep’.
Similarly, ‘tify’ is not a synonym for ‘nonotify’ (the inversion of
‘notify’).
Some options also have one or more single letter names. There are two
sets of single letter options: one used by default, and another used
to emulate sh/ksh (used when the SH_OPTION_LETTERS option is set).
The single letter options can be used on the shell command line, or
with the set, setopt and unsetopt builtins, as normal Unix options
preceded by ‘-’.
The sense of the single letter options may be inverted by using ‘+’
instead of ‘-’. Some of the single letter option names refer to an
option being off, in which case the inversion of that name refers to
the option being on. For example, ‘+n’ is the short name of ‘exec’,
and ‘-n’ is the short name of its inversion, ‘noexec’.
In strings of single letter options supplied to the shell at startup,
trailing whitespace will be ignored; for example the string ‘-f ’
will be treated just as ‘-f’, but the string ‘-f i’ is an error. This
is because many systems which implement the ‘#!’ mechanism for calling
scripts do not strip trailing whitespace.
DESCRIPTION OF OPTIONS
In the following list, options set by default in all emulations are
marked <D>; those set by default only in csh, ksh, sh, or zsh emula-
tions are marked <C>, <K>, <S>, <Z> as appropriate. When listing
options (by ‘setopt’, ‘unsetopt’, ‘set -o’ or ‘set +o’), those turned
on by default appear in the list prefixed with ‘no’. Hence (unless
KSH_OPTION_PRINT is set), ‘setopt’ shows all options whose settings
are changed from the default.
ALIASES <D>
Expand aliases.
ALL_EXPORT (-a, ksh: -a)
All parameters subsequently defined are automatically exported.
ALWAYS_LAST_PROMPT <D>
If unset, key functions that list completions try to return to
the last prompt if given a numeric argument. If set these func-
tions try to return to the last prompt if given no numeric
argument.
ALWAYS_TO_END
If a completion is performed with the cursor within a word, and
a full completion is inserted, the cursor is moved to the end
of the word. That is, the cursor is moved to the end of the
word if either a single match is inserted or menu completion is
performed.
APPEND_HISTORY <D>
If this is set, zsh sessions will append their history list to
the history file, rather than overwrite it. Thus, multiple par-
allel zsh sessions will all have their history lists added to
the history file, in the order they are killed.
AUTO_CD (-J)
If a command is issued that can’t be executed as a normal com-
mand, and the command is the name of a directory, perform the
cd command to that directory.
AUTO_CONTINUE
With this option set, stopped jobs that are removed from the
job table with the disown builtin command are automatically
sent a CONT signal to make them running.
AUTO_LIST (-9) <D>
Automatically list choices on an ambiguous completion.
AUTO_MENU <D>
Automatically use menu completion after the second consecutive
request for completion, for example by pressing the tab key
repeatedly. This option is overridden by MENU_COMPLETE.
AUTO_NAME_DIRS
Any parameter that is set to the absolute name of a directory
immediately becomes a name for that directory, that will be
used by the ‘%~’ and related prompt sequences, and will be
available when completion is performed on a word starting with
‘~’. (Otherwise, the parameter must be used in the form
‘~param’ first.)
AUTO_PARAM_KEYS <D>
If a parameter name was completed and a following character
(normally a space) automatically inserted, and the next
character typed is one of those that have to come directly
after the name (like ‘}’, ‘:’, etc.), the automatically added
character is deleted, so that the character typed comes immedi-
ately after the parameter name. Completion in a brace expan-
sion is affected similarly: the added character is a ‘,’, which
will be removed if ‘}’ is typed next.
AUTO_PARAM_SLASH <D>
If a parameter is completed whose content is the name of a
directory, then add a trailing slash instead of a space.
AUTO_PUSHD (-N)
Make cd push the old directory onto the directory stack.
AUTO_REMOVE_SLASH <D>
When the last character resulting from a completion is a slash
and the next character typed is a word delimiter, a slash, or a
character that ends a command (such as a semicolon or an amper-
sand), remove the slash.
AUTO_RESUME (-W)
Treat single word simple commands without redirection as candi-
dates for resumption of an existing job.
BAD_PATTERN (+2) <C> <Z>
If a pattern for filename generation is badly formed, print an
error message. (If this option is unset, the pattern will be
left unchanged.)
BANG_HIST (+K) <C> <Z>
Perform textual history expansion, csh-style, treating the
character ‘!’ specially.
BARE_GLOB_QUAL <Z>
In a glob pattern, treat a trailing set of parentheses as a
qualifier list, if it contains no ‘|’, ‘(’ or (if special) ‘~’
characters. See the section ‘Filename Generation’.
BASH_AUTO_LIST
On an ambiguous completion, automatically list choices when the
completion function is called twice in succession. This takes
precedence over AUTO_LIST. The setting of LIST_AMBIGUOUS is
respected. If AUTO_MENU is set, the menu behaviour will then
start with the third press. Note that this will not work with
MENU_COMPLETE, since repeated completion calls immediately
cycle through the list in that case.
BEEP (+B) <D>
Beep on error in ZLE.
BG_NICE (-6) <C> <Z>
Run all background jobs at a lower priority. This option is
set by default.
BRACE_CCL
Expand expressions in braces which would not otherwise undergo
brace expansion to a lexically ordered list of all the charac-
ters. See the section ‘Brace Expansion’.
BSD_ECHO <S>
Make the echo builtin compatible with the BSD echo(1) command.
This disables backslashed escape sequences in echo strings
unless the -e option is specified.
CASE_GLOB <D>
Make globbing (filename generation) sensitive to case. Note
that other uses of patterns are always sensitive to case. If
the option is unset, the presence of any character which is
special to filename generation will cause case-insensitive
matching. For example, cvs(/) can match the directory CVS
owing to the presence of the globbing flag (unless the option
BARE_GLOB_QUAL is unset).
C_BASES
Output hexadecimal numbers in the standard C format, for exam-
ple ‘0xFF’ instead of the usual ‘16#FF’. If the option
OCTAL_ZEROES is also set (it is not by default), octal numbers
will be treated similarly and hence appear as ‘077’ instead of
‘8#77’. This option has no effect on the choice of the output
base, nor on the output of bases other than hexadecimal and
octal. Note that these formats will be understood on input
irrespective of the setting of C_BASES.
CDABLE_VARS (-T)
If the argument to a cd command (or an implied cd with the
AUTO_CD option set) is not a directory, and does not begin with
a slash, try to expand the expression as if it were preceded by
a ‘~’ (see the section ‘Filename Expansion’).
CHASE_DOTS
When changing to a directory containing a path segment ‘..’
which would otherwise be treated as canceling the previous seg-
ment in the path (in other words, ‘foo/..’ would be removed
from the path, or if ‘..’ is the first part of the path, the
last part of $PWD would be deleted), instead resolve the path
to the physical directory. This option is overridden by
CHASE_LINKS.
For example, suppose /foo/bar is a link to the directory
/alt/rod. Without this option set, ‘cd /foo/bar/..’ changes to
/foo; with it set, it changes to /alt. The same applies if the
current directory is /foo/bar and ‘cd ..’ is used. Note that
all other symbolic links in the path will also be resolved.
CHASE_LINKS (-w)
Resolve symbolic links to their true values when changing
directory. This also has the effect of CHASE_DOTS, i.e. a ‘..’
path segment will be treated as referring to the physical par-
ent, even if the preceding path segment is a symbolic link.
CHECK_JOBS <Z>
Report the status of background and suspended jobs before exit-
ing a shell with job control; a second attempt to exit the
shell will succeed. NO_CHECK_JOBS is best used only in combi-
nation with NO_HUP, else such jobs will be killed automati-
cally.
The check is omitted if the commands run from the previous com-
mand line included a ‘jobs’ command, since it is assumed the
user is aware that there are background or suspended jobs. A
‘jobs’ command run from the precmd function is not counted for
this purpose.
CLOBBER (+C, ksh: +C) <D>
Allows ‘>’ redirection to truncate existing files, and ‘>>’ to
create files. Otherwise ‘>!’ or ‘>|’ must be used to truncate
a file, and ‘>>!’ or ‘>>|’ to create a file.
COMPLETE_ALIASES
Prevents aliases on the command line from being internally sub-
stituted before completion is attempted. The effect is to make
the alias a distinct command for completion purposes.
COMPLETE_IN_WORD
If unset, the cursor is set to the end of the word if comple-
tion is started. Otherwise it stays there and completion is
done from both ends.
CORRECT (-0)
Try to correct the spelling of commands. Note that, when the
HASH_LIST_ALL option is not set or when some directories in the
path are not readable, this may falsely report spelling errors
the first time some commands are used.
CORRECT_ALL (-O)
Try to correct the spelling of all arguments in a line.
CSH_JUNKIE_HISTORY <C>
A history reference without an event specifier will always
refer to the previous command. Without this option, such a
history reference refers to the same event as the previous his-
tory reference, defaulting to the previous command.
CSH_JUNKIE_LOOPS <C>
Allow loop bodies to take the form ‘list; end’ instead of ‘do
list; done’.
CSH_JUNKIE_QUOTES <C>
Changes the rules for single- and double-quoted text to match
that of csh. These require that embedded newlines be preceded
by a backslash; unescaped newlines will cause an error message.
In double-quoted strings, it is made impossible to escape ‘$’,
‘‘’ or ‘"’ (and ‘\’ itself no longer needs escaping). Command
substitutions are only expanded once, and cannot be nested.
CSH_NULLCMD <C>
Do not use the values of NULLCMD and READNULLCMD when running
redirections with no command. This make such redirections fail
(see the section ‘Redirection’).
CSH_NULL_GLOB <C>
If a pattern for filename generation has no matches, delete the
pattern from the argument list; do not report an error unless
all the patterns in a command have no matches. Overrides
NOMATCH.
DVORAK Use the Dvorak keyboard instead of the standard qwerty keyboard
as a basis for examining spelling mistakes for the CORRECT and
CORRECT_ALL options and the spell-word editor command.
EMACS If ZLE is loaded, turning on this option has the equivalent
effect of ‘bindkey -e’. In addition, the VI option is unset.
Turning it off has no effect. The option setting is not guar-
anteed to reflect the current keymap. This option is provided
for compatibility; bindkey is the recommended interface.
EQUALS <Z>
Perform = filename expansion. (See the section ‘Filename
Expansion’.)
ERR_EXIT (-e, ksh: -e)
If a command has a non-zero exit status, execute the ZERR trap,
if set, and exit. This is disabled while running initializa-
tion scripts. cidnex(return from function, on error)
ERR_RETURN
If a command has a non-zero exit status, return immediately
from the enclosing function. The logic is identical to that
for ERR_EXIT, except that an implicit return statement is exe-
cuted instead of an exit. This will trigger an exit at the
outermost level of a non-interactive script.
EXEC (+n, ksh: +n) <D>
Do execute commands. Without this option, commands are read
and checked for syntax errors, but not executed. This option
cannot be turned off in an interactive shell, except when ‘-n’
is supplied to the shell at startup.
EXTENDED_GLOB
Treat the ‘#’, ‘~’ and ‘^’ characters as part of patterns for
filename generation, etc. (An initial unquoted ‘~’ always pro-
duces named directory expansion.)
EXTENDED_HISTORY <C>
Save each command’s beginning timestamp (in seconds since the
epoch) and the duration (in seconds) to the history file. The
format of this prefixed data is:
‘:<beginning time>:<elapsed seconds>:<command>’.
FLOW_CONTROL <D>
If this option is unset, output flow control via start/stop
characters (usually assigned to ^S/^Q) is disabled in the
shell’s editor.
FUNCTION_ARGZERO <C> <Z>
When executing a shell function or sourcing a script, set $0
temporarily to the name of the function/script.
GLOB (+F, ksh: +f) <D>
Perform filename generation (globbing). (See the section
‘Filename Generation’.)
GLOBAL_EXPORT (<Z>)
If this option is set, passing the -x flag to the builtins
declare, float, integer, readonly and typeset (but not local)
will also set the -g flag; hence parameters exported to the
environment will not be made local to the enclosing function,
unless they were already or the flag +g is given explicitly.
If the option is unset, exported parameters will be made local
in just the same way as any other parameter.
This option is set by default for backward compatibility; it is
not recommended that its behaviour be relied upon. Note that
the builtin export always sets both the -x and -g flags, and
hence its effect extends beyond the scope of the enclosing
function; this is the most portable way to achieve this
behaviour.
GLOBAL_RCS (-d) <D>
If this option is unset, the startup files /etc/zprofile,
/etc/zshrc, /etc/zlogin and /etc/zlogout will not be run. It
can be disabled and re-enabled at any time, including inside
local startup files (.zshrc, etc.).
GLOB_ASSIGN <C>
If this option is set, filename generation (globbing) is per-
formed on the right hand side of scalar parameter assignments
of the form ‘name=pattern (e.g. ‘foo=*’). If the result has
more than one word the parameter will become an array with
those words as arguments. This option is provided for backwards
compatibility only: globbing is always performed on the right
hand side of array assignments of the form ‘name=(value)’ (e.g.
‘foo=(*)’) and this form is recommended for clarity; with this
option set, it is not possible to predict whether the result
will be an array or a scalar.
GLOB_COMPLETE
When the current word has a glob pattern, do not insert all the
words resulting from the expansion but generate matches as for
completion and cycle through them like MENU_COMPLETE. The
matches are generated as if a ‘*’ was added to the end of the
word, or inserted at the cursor when COMPLETE_IN_WORD is set.
This actually uses pattern matching, not globbing, so it works
not only for files but for any completion, such as options,
user names, etc.
GLOB_DOTS (-4)
Do not require a leading ‘.’ in a filename to be matched
explicitly.
GLOB_SUBST <C> <K> <S>
Treat any characters resulting from parameter expansion as
being eligible for file expansion and filename generation, and
any characters resulting from command substitution as being
eligible for filename generation. Braces (and commas in
between) do not become eligible for expansion.
HASH_CMDS <D>
Note the location of each command the first time it is exe-
cuted. Subsequent invocations of the same command will use the
saved location, avoiding a path search. If this option is
unset, no path hashing is done at all. However, when CORRECT
is set, commands whose names do not appear in the functions or
aliases hash tables are hashed in order to avoid reporting them
as spelling errors.
HASH_DIRS <D>
Whenever a command name is hashed, hash the directory contain-
ing it, as well as all directories that occur earlier in the
path. Has no effect if neither HASH_CMDS nor CORRECT is set.
HASH_LIST_ALL <D>
Whenever a command completion is attempted, make sure the
entire command path is hashed first. This makes the first com-
pletion slower.
HIST_ALLOW_CLOBBER
Add ‘|’ to output redirections in the history. This allows
history references to clobber files even when CLOBBER is unset.
HIST_BEEP <D>
Beep when an attempt is made to access a history entry which
isn’t there.
HIST_EXPIRE_DUPS_FIRST
If the internal history needs to be trimmed to add the current
command line, setting this option will cause the oldest history
event that has a duplicate to be lost before losing a unique
event from the list. You should be sure to set the value of
HISTSIZE to a larger number than SAVEHIST in order to give you
some room for the duplicated events, otherwise this option will
behave just like HIST_IGNORE_ALL_DUPS once the history fills up
with unique events.
HIST_FIND_NO_DUPS
When searching for history entries in the line editor, do not
display duplicates of a line previously found, even if the
duplicates are not contiguous.
HIST_IGNORE_ALL_DUPS
If a new command line being added to the history list dupli-
cates an older one, the older command is removed from the list
(even if it is not the previous event).
HIST_IGNORE_DUPS (-h)
Do not enter command lines into the history list if they are
duplicates of the previous event.
HIST_IGNORE_SPACE (-g)
Remove command lines from the history list when the first char-
acter on the line is a space, or when one of the expanded
aliases contains a leading space. Note that the command
lingers in the internal history until the next command is
entered before it vanishes, allowing you to briefly reuse or
edit the line. If you want to make it vanish right away with-
out entering another command, type a space and press return.
HIST_NO_FUNCTIONS
Remove function definitions from the history list. Note that
the function lingers in the internal history until the next
command is entered before it vanishes, allowing you to briefly
reuse or edit the definition.
HIST_NO_STORE
Remove the history (fc -l) command from the history list when
invoked. Note that the command lingers in the internal history
until the next command is entered before it vanishes, allowing
you to briefly reuse or edit the line.
HIST_REDUCE_BLANKS
Remove superfluous blanks from each command line being added to
the history list.
HIST_SAVE_NO_DUPS
When writing out the history file, older commands that dupli-
cate newer ones are omitted.
HIST_VERIFY
Whenever the user enters a line with history expansion, don’t
execute the line directly; instead, perform history expansion
and reload the line into the editing buffer.
HUP <Z>
Send the HUP signal to running jobs when the shell exits.
IGNORE_BRACES (-I) <S>
Do not perform brace expansion.
IGNORE_EOF (-7)
Do not exit on end-of-file. Require the use of exit or logout
instead. However, ten consecutive EOFs will cause the shell to
exit anyway, to avoid the shell hanging if its tty goes away.
Also, if this option is set and the Zsh Line Editor is used,
widgets implemented by shell functions can be bound to EOF
(normally Control-D) without printing the normal warning mes-
sage. This works only for normal widgets, not for completion
widgets.
INC_APPEND_HISTORY
This options works like APPEND_HISTORY except that new history
lines are added to the $HISTFILE incrementally (as soon as they
are entered), rather than waiting until the shell is killed.
The file is periodically trimmed to the number of lines speci-
fied by $SAVEHIST, but can exceed this value between trimmings.
INTERACTIVE (-i, ksh: -i)
This is an interactive shell. This option is set upon initial-
isation if the standard input is a tty and commands are being
read from standard input. (See the discussion of SHIN_STDIN.)
This heuristic may be overridden by specifying a state for this
option on the command line. The value of this option cannot be
changed anywhere other than the command line.
INTERACTIVE_COMMENTS (-k) <K> <S>
Allow comments even in interactive shells.
KSH_ARRAYS <K> <S>
Emulate ksh array handling as closely as possible. If this
option is set, array elements are numbered from zero, an array
parameter without subscript refers to the first element instead
of the whole array, and braces are required to delimit a sub-
script (‘${path[2]}’ rather than just ‘$path[2]’).
KSH_AUTOLOAD <K> <S>
Emulate ksh function autoloading. This means that when a func-
tion is autoloaded, the corresponding file is merely executed,
and must define the function itself. (By default, the function
is defined to the contents of the file. However, the most com-
mon ksh-style case - of the file containing only a simple defi-
nition of the function - is always handled in the ksh-compati-
ble manner.)
KSH_GLOB <K>
In pattern matching, the interpretation of parentheses is
affected by a preceding ‘@’, ‘*’, ‘+’, ‘?’ or ‘!’. See the
section ‘Filename Generation’.
KSH_OPTION_PRINT <K>
Alters the way options settings are printed: instead of sepa-
rate lists of set and unset options, all options are shown,
marked ‘on’ if they are in the non-default state, ‘off’ other-
wise.
KSH_TYPESET <K>
Alters the way arguments to the typeset family of commands,
including declare, export, float, integer, local and readonly,
are processed. Without this option, zsh will perform normal
word splitting after command and parameter expansion in argu-
ments of an assignment; with it, word splitting does not take
place in those cases.
LIST_AMBIGUOUS <D>
This option works when AUTO_LIST or BASH_AUTO_LIST is also set.
If there is an unambiguous prefix to insert on the command
line, that is done without a completion list being displayed;
in other words, auto-listing behaviour only takes place when
nothing would be inserted. In the case of BASH_AUTO_LIST, this
means that the list will be delayed to the third call of the
function.
LIST_BEEP <D>
Beep on an ambiguous completion. More accurately, this forces
the completion widgets to return status 1 on an ambiguous com-
pletion, which causes the shell to beep if the option BEEP is
also set; this may be modified if completion is called from a
user-defined widget.
LIST_PACKED
Try to make the completion list smaller (occupying less lines)
by printing the matches in columns with different widths.
LIST_ROWS_FIRST
Lay out the matches in completion lists sorted horizontally,
that is, the second match is to the right of the first one, not
under it as usual.
LIST_TYPES (-X) <D>
When listing files that are possible completions, show the type
of each file with a trailing identifying mark.
LOCAL_OPTIONS <K>
If this option is set at the point of return from a shell func-
tion, all the options (including this one) which were in force
upon entry to the function are restored. Otherwise, only this
option and the XTRACE and PRINT_EXIT_VALUE options are
restored. Hence if this is explicitly unset by a shell func-
tion the other options in force at the point of return will
remain so. A shell function can also guarantee itself a known
shell configuration with a formulation like ‘emulate -L zsh’;
the -L activates LOCAL_OPTIONS.
LOCAL_TRAPS <K>
If this option is set when a signal trap is set inside a func-
tion, then the previous status of the trap for that signal will
be restored when the function exits. Note that this option
must be set prior to altering the trap behaviour in a function;
unlike LOCAL_OPTIONS, the value on exit from the function is
irrelevant. However, it does not need to be set before any
global trap for that to be correctly restored by a function.
For example,
unsetopt localtraps
trap - INT
fn() { setopt localtraps; trap ’’ INT; sleep 3; }
will restore normally handling of SIGINT after the function
exits.
LOGIN (-l, ksh: -l)
This is a login shell. If this option is not explicitly set,
the shell is a login shell if the first character of the
argv[0] passed to the shell is a ‘-’.
LONG_LIST_JOBS (-R)
List jobs in the long format by default.
MAGIC_EQUAL_SUBST
All unquoted arguments of the form ‘anything=expression’
appearing after the command name have filename expansion (that
is, where expression has a leading ‘~’ or ‘=’) performed on
expression as if it were a parameter assignment. The argument
is not otherwise treated specially; it is passed to the command
as a single argument, and not used as an actual parameter
assignment. For example, in echo foo=~/bar:~/rod, both occur-
rences of ~ would be replaced. Note that this happens anyway
with typeset and similar statements.
This option respects the setting of the KSH_TYPESET option. In
other words, if both options are in effect, arguments looking
like assignments will not undergo wordsplitting.
MAIL_WARNING (-U)
Print a warning message if a mail file has been accessed since
the shell last checked.
MARK_DIRS (-8, ksh: -X)
Append a trailing ‘/’ to all directory names resulting from
filename generation (globbing).
MENU_COMPLETE (-Y)
On an ambiguous completion, instead of listing possibilities or
beeping, insert the first match immediately. Then when comple-
tion is requested again, remove the first match and insert the
second match, etc. When there are no more matches, go back to
the first one again. reverse-menu-complete may be used to loop
through the list in the other direction. This option overrides
AUTO_MENU.
MONITOR (-m, ksh: -m)
Allow job control. Set by default in interactive shells.
MULTIOS <Z>
Perform implicit tees or cats when multiple redirections are
attempted (see the section ‘Redirection’).
NOMATCH (+3) <C> <Z>
If a pattern for filename generation has no matches, print an
error, instead of leaving it unchanged in the argument list.
This also applies to file expansion of an initial ‘~’ or ‘=’.
NOTIFY (-5, ksh: -b) <Z>
Report the status of background jobs immediately, rather than
waiting until just before printing a prompt.
NULL_GLOB (-G)
If a pattern for filename generation has no matches, delete the
pattern from the argument list instead of reporting an error.
Overrides NOMATCH.
NUMERIC_GLOB_SORT
If numeric filenames are matched by a filename generation pat-
tern, sort the filenames numerically rather than lexicographi-
cally.
OCTAL_ZEROES <S>
Interpret any integer constant beginning with a 0 as octal, per
IEEE Std 1003.2-1992 (ISO 9945-2:1993). This is not enabled by
default as it causes problems with parsing of, for example,
date and time strings with leading zeroes.
OVERSTRIKE
Start up the line editor in overstrike mode.
PATH_DIRS (-Q)
Perform a path search even on command names with slashes in
them. Thus if ‘/usr/local/bin’ is in the user’s path, and he
or she types ‘X11/xinit’, the command
‘/usr/local/bin/X11/xinit’ will be executed (assuming it
exists). Commands explicitly beginning with ‘/’, ‘./’ or ‘../’
are not subject to the path search. This also applies to the .
builtin.
Note that subdirectories of the current directory are always
searched for executables specified in this form. This takes
place before any search indicated by this option, and regard-
less of whether ‘.’ or the current directory appear in the com-
mand search path.
POSIX_BUILTINS <K> <S>
When this option is set the command builtin can be used to exe-
cute shell builtin commands. Parameter assignments specified
before shell functions and special builtins are kept after the
command completes unless the special builtin is prefixed with
the command builtin. Special builtins are ., :, break, con-
tinue, declare, eval, exit, export, integer, local, readonly,
return, set, shift, source, times, trap and unset.
PRINT_EIGHT_BIT
Print eight bit characters literally in completion lists, etc.
This option is not necessary if your system correctly returns
the printability of eight bit characters (see ctype(3)).
PRINT_EXIT_VALUE (-1)
Print the exit value of programs with non-zero exit status.
PRIVILEGED (-p, ksh: -p)
Turn on privileged mode. This is enabled automatically on
startup if the effective user (group) ID is not equal to the
real user (group) ID. Turning this option off causes the
effective user and group IDs to be set to the real user and
group IDs. This option disables sourcing user startup files.
If zsh is invoked as ‘sh’ or ‘ksh’ with this option set,
/etc/suid_profile is sourced (after /etc/profile on interactive
shells). Sourcing ~/.profile is disabled and the contents of
the ENV variable is ignored. This option cannot be changed
using the -m option of setopt and unsetopt, and changing it
inside a function always changes it globally regardless of the
LOCAL_OPTIONS option.
PROMPT_BANG <K>
If set, ‘!’ is treated specially in prompt expansion. See the
section ‘Prompt Expansion’.
PROMPT_CR (+V) <D>
Print a carriage return just before printing a prompt in the
line editor. This is on by default as multi-line editing is
only possible if the editor knows where the start of the line
appears.
PROMPT_PERCENT <C> <Z>
If set, ‘%’ is treated specially in prompt expansion. See the
section ‘Prompt Expansion’.
PROMPT_SUBST <K>
If set, parameter expansion, command substitution and arith-
metic expansion are performed in prompts.
PUSHD_IGNORE_DUPS
Don’t push multiple copies of the same directory onto the
directory stack.
PUSHD_MINUS
Exchanges the meanings of ‘+’ and ‘-’ when used with a number
to specify a directory in the stack.
PUSHD_SILENT (-E)
Do not print the directory stack after pushd or popd.
PUSHD_TO_HOME (-D)
Have pushd with no arguments act like ‘pushd $HOME’.
RC_EXPAND_PARAM (-P)
Array expansions of the form ‘foo${xx}bar’, where the parameter
xx is set to (a b c), are substituted with ‘fooabar foobbar
foocbar’ instead of the default ‘fooa b cbar’.
RC_QUOTES
Allow the character sequence ‘’’’ to signify a single quote
within singly quoted strings. Note this does not apply in
quoted strings using the format $’...’, where a backslashed
single quote can be used.
RCS (+f) <D>
After /etc/zshenv is sourced on startup, source the .zshenv,
/etc/zprofile, .zprofile, /etc/zshrc, .zshrc, /etc/zlogin,
.zlogin, and .zlogout files, as described in the section
‘Files’. If this option is unset, the /etc/zshenv file is
still sourced, but any of the others will not be; it can be set
at any time to prevent the remaining startup files after the
currently executing one from being sourced.
REC_EXACT (-S)
In completion, recognize exact matches even if they are ambigu-
ous.
RESTRICTED (-r)
Enables restricted mode. This option cannot be changed using
unsetopt, and setting it inside a function always changes it
globally regardless of the LOCAL_OPTIONS option. See the sec-
tion ‘Restricted Shell’.
RM_STAR_SILENT (-H) <K> <S>
Do not query the user before executing ‘rm *’ or ‘rm path/*’.
RM_STAR_WAIT
If querying the user before executing ‘rm *’ or ‘rm path/*’,
first wait ten seconds and ignore anything typed in that time.
This avoids the problem of reflexively answering ‘yes’ to the
query when one didn’t really mean it. The wait and query can
always be avoided by expanding the ‘*’ in ZLE (with tab).
SHARE_HISTORY <K>
This option both imports new commands from the history file,
and also causes your typed commands to be appended to the his-
tory file (the latter is like specifying INC_APPEND_HISTORY).
The history lines are also output with timestamps ala
EXTENDED_HISTORY (which makes it easier to find the spot where
we left off reading the file after it gets re-written).
By default, history movement commands visit the imported lines
as well as the local lines, but you can toggle this on and off
with the set-local-history zle binding. It is also possible to
create a zle widget that will make some commands ignore
imported commands, and some include them.
If you find that you want more control over when commands get
imported, you may wish to turn SHARE_HISTORY off,
INC_APPEND_HISTORY on, and then manually import commands when-
ever you need them using ‘fc -RI’.
SH_FILE_EXPANSION <K> <S>
Perform filename expansion (e.g., ~ expansion) before parameter
expansion, command substitution, arithmetic expansion and brace
expansion. If this option is unset, it is performed after
brace expansion, so things like ‘~$USERNAME’ and ‘~{pfal-
stad,rc}’ will work.
SH_GLOB <K> <S>
Disables the special meaning of ‘(’, ‘|’, ‘)’ and ’<’ for glob-
bing the result of parameter and command substitutions, and in
some other places where the shell accepts patterns. This
option is set by default if zsh is invoked as sh or ksh.
SHIN_STDIN (-s, ksh: -s)
Commands are being read from the standard input. Commands are
read from standard input if no command is specified with -c and
no file of commands is specified. If SHIN_STDIN is set explic-
itly on the command line, any argument that would otherwise
have been taken as a file to run will instead be treated as a
normal positional parameter. Note that setting or unsetting
this option on the command line does not necessarily affect the
state the option will have while the shell is running - that is
purely an indicator of whether on not commands are actually
being read from standard input. The value of this option can-
not be changed anywhere other than the command line.
SH_NULLCMD <K> <S>
Do not use the values of NULLCMD and READNULLCMD when doing
redirections, use ‘:’ instead (see the section ‘Redirection’).
SH_OPTION_LETTERS <K> <S>
If this option is set the shell tries to interpret single let-
ter options (which are used with set and setopt) like ksh does.
This also affects the value of the - special parameter.
SHORT_LOOPS <C> <Z>
Allow the short forms of for, repeat, select, if, and function
constructs.
SH_WORD_SPLIT (-y) <K> <S>
Causes field splitting to be performed on unquoted parameter
expansions. Note that this option has nothing to do with word
splitting. (See the section ‘Parameter Expansion’.)
SINGLE_COMMAND (-t, ksh: -t)
If the shell is reading from standard input, it exits after a
single command has been executed. This also makes the shell
non-interactive, unless the INTERACTIVE option is explicitly
set on the command line. The value of this option cannot be
changed anywhere other than the command line.
SINGLE_LINE_ZLE (-M) <K>
Use single-line command line editing instead of multi-line.
SUN_KEYBOARD_HACK (-L)
If a line ends with a backquote, and there are an odd number of
backquotes on the line, ignore the trailing backquote. This is
useful on some keyboards where the return key is too small, and
the backquote key lies annoyingly close to it.
TRANSIENT_RPROMPT
Remove any right prompt from display when accepting a command
line. This may be useful with terminals with other cut/paste
methods.
TYPESET_SILENT
If this is unset, executing any of the ‘typeset’ family of com-
mands with no options and a list of parameters that have no
values to be assigned but already exist will display the value
of the parameter. If the option is set, they will only be
shown when parameters are selected with the ‘-m’ option. The
option ‘-p’ is available whether or not the option is set.
UNSET (+u, ksh: +u) <K> <S> <Z>
Treat unset parameters as if they were empty when substituting.
Otherwise they are treated as an error.
VERBOSE (-v, ksh: -v)
Print shell input lines as they are read.
VI If ZLE is loaded, turning on this option has the equivalent
effect of ‘bindkey -v’. In addition, the EMACS option is
unset. Turning it off has no effect. The option setting is
not guaranteed to reflect the current keymap. This option is
provided for compatibility; bindkey is the recommended inter-
face.
XTRACE (-x, ksh: -x)
Print commands and their arguments as they are executed.
ZLE (-Z)
Use the zsh line editor. Set by default in interactive shells
connected to a terminal.
OPTION ALIASES
Some options have alternative names. These aliases are never used for
output, but can be used just like normal option names when specifying
options to the shell.
BRACE_EXPAND
NO_IGNORE_BRACES (ksh and bash compatibility)
DOT_GLOB
GLOB_DOTS (bash compatibility)
HASH_ALL
HASH_CMDS (bash compatibility)
HIST_APPEND
APPEND_HISTORY (bash compatibility)
HIST_EXPAND
BANG_HIST (bash compatibility)
LOG NO_HIST_NO_FUNCTIONS (ksh compatibility)
MAIL_WARN
MAIL_WARNING (bash compatibility)
ONE_CMD
SINGLE_COMMAND (bash compatibility)
PHYSICAL
CHASE_LINKS (ksh and bash compatibility)
PROMPT_VARS
PROMPT_SUBST (bash compatibility)
STDIN SHIN_STDIN (ksh compatibility)
TRACK_ALL
HASH_CMDS (ksh compatibility)
SINGLE LETTER OPTIONS
Default set
-0 CORRECT
-1 PRINT_EXIT_VALUE
-2 NO_BAD_PATTERN
-3 NO_NOMATCH
-4 GLOB_DOTS
-5 NOTIFY
-6 BG_NICE
-7 IGNORE_EOF
-8 MARK_DIRS
-9 AUTO_LIST
-B NO_BEEP
-C NO_CLOBBER
-D PUSHD_TO_HOME
-E PUSHD_SILENT
-F NO_GLOB
-G NULL_GLOB
-H RM_STAR_SILENT
-I IGNORE_BRACES
-J AUTO_CD
-K NO_BANG_HIST
-L SUN_KEYBOARD_HACK
-M SINGLE_LINE_ZLE
-N AUTO_PUSHD
-O CORRECT_ALL
-P RC_EXPAND_PARAM
-Q PATH_DIRS
-R LONG_LIST_JOBS
-S REC_EXACT
-T CDABLE_VARS
-U MAIL_WARNING
-V NO_PROMPT_CR
-W AUTO_RESUME
-X LIST_TYPES
-Y MENU_COMPLETE
-Z ZLE
-a ALL_EXPORT
-e ERR_EXIT
-f NO_RCS
-g HIST_IGNORE_SPACE
-h HIST_IGNORE_DUPS
-i INTERACTIVE
-k INTERACTIVE_COMMENTS
-l LOGIN
-m MONITOR
-n NO_EXEC
-p PRIVILEGED
-r RESTRICTED
-s SHIN_STDIN
-t SINGLE_COMMAND
-u NO_UNSET
-v VERBOSE
-w CHASE_LINKS
-x XTRACE
-y SH_WORD_SPLIT
sh/ksh emulation set
-C NO_CLOBBER
-X MARK_DIRS
-a ALL_EXPORT
-b NOTIFY
-e ERR_EXIT
-f NO_GLOB
-i INTERACTIVE
-l LOGIN
-m MONITOR
-n NO_EXEC
-p PRIVILEGED
-r RESTRICTED
-s SHIN_STDIN
-t SINGLE_COMMAND
-u NO_UNSET
-v VERBOSE
-x XTRACE
Also note
-A Used by set for setting arrays
-b Used on the command line to specify end of option processing
-c Used on the command line to specify a single command
-m Used by setopt for pattern-matching option setting
-o Used in all places to allow use of long option names
ZSHBUILTINS(1) ZSHBUILTINS(1)
-s Used by set to sort positional parameters
NAME
zshbuiltins - zsh built-in commands
SHELL BUILTIN COMMANDS
- simple command
See the section ‘Precommand Modifiers’.
. file [ arg ... ]
Read commands from file and execute them in the current shell
environment.
If file does not contain a slash, or if PATH_DIRS is set, the
shell looks in the components of $path to find the directory
containing file. Files in the current directory are not read
unless ‘.’ appears somewhere in $path. If a file named
‘file.zwc’ is found, is newer than file, and is the compiled
form (created with the zcompile builtin) of file, then commands
are read from that file instead of file.
If any arguments arg are given, they become the positional
parameters; the old positional parameters are restored when the
file is done executing. The exit status is the exit status of
the last command executed.
: [ arg ... ]
This command does nothing, although normal argument expansions
is performed which may have effects on shell parameters. A
zero exit code is returned.
alias [ {+|-}gmrsL ] [ name[=value] ... ]
For each name with a corresponding value, define an alias with
that value. A trailing space in value causes the next word to
be checked for alias expansion. If the -g flag is present,
define a global alias; global aliases are expanded even if they
do not occur in command position.
If the -s flags is present, define a suffix alias: if the com-
mand word on a command line is in the form ‘text.name’, where
text is any non-empty string, it is replaced by the text ‘value
text.name’. Note that name is treated as a literal string, not
a pattern. A trailing space in value is not special in this
case. For example,
alias -s ps=gv
will cause the command ‘*.ps’ to be expanded to ‘gv *.ps’. As
alias expansion is carried out earlier than globbing, the
‘*.ps’ will then be expanded. Suffix aliases constitute a dif-
ferent name space from other aliases (so in the above example
it is still possible to create an alias for the command ps) and
the two sets are never listed together.
For each name with no value, print the value of name, if any.
With no arguments, print all currently defined aliases other
than suffix aliases. If the -m flag is given the arguments are
taken as patterns (they should be quoted to preserve them from
being interpreted as glob patterns), and the aliases matching
these patterns are printed. When printing aliases and one of
the -g, -r or -s flags is present, restrict the printing to
global, regular or suffix aliases, respectively; a regular
alias is one which is neither a global nor a suffix alias.
Using ‘+’ instead of ‘-’, or ending the option list with a sin-
gle ‘+’, prevents the values of the aliases from being printed.
If the -L flag is present, then print each alias in a manner
suitable for putting in a startup script. The exit status is
nonzero if a name (with no value) is given for which no alias
has been defined.
autoload [ {+|-}UXmt ] [ -wkz ] [ name ... ]
Equivalent to functions -u, with the exception of -X/+X, -w, -k
and -z.
The flag -X may be used only inside a shell function, and may
not be followed by a name. It causes the calling function to
be marked for autoloading and then immediately loaded and exe-
cuted, with the current array of positional parameters as argu-
ments. This replaces the previous definition of the function.
If no function definition is found, an error is printed and the
function remains undefined and marked for autoloading.
The flag +X attempts to load each name as an autoloaded func-
tion, but does not execute it. The exit status is zero (suc-
cess) if the function was not previously defined and a defini-
tion for it was found. This does not replace any existing def-
inition of the function. The exit status is nonzero (failure)
if the function was already defined or when no definition was
found. In the latter case the function remains undefined and
marked for autoloading.
The flag +X may be combined with either -k or -z to make the
function be loaded using ksh-style or zsh-style autoloading,
respectively. If neither is given, the current setting of the
KSH_AUTOLOAD options determines how the function is loaded.
With ksh-style autoloading, the contents of the file will not
be executed immediately. Instead, the function created will
contain the contents of the file plus a call to the function
itself appended to it, thus given normal ksh autoloading
behaviour on the first call to the function.
With the -w flag, the names are taken as names of files com-
piled with the zcompile builtin, and all functions defined in
them are marked for autoloading.
bg [ job ... ]
job ... &
Put each specified job in the background, or the current job if
none is specified.
bindkey
See the section ‘Zle Builtins’ in zshzle(1).
break [ n ]
Exit from an enclosing for, while, until, select or repeat
loop. If n is specified, then break n levels instead of just
one.
builtin name [ args ... ]
Executes the builtin name, with the given args.
bye Same as exit.
cap See the section ‘The zsh/cap Module’ in zshmodules(1).
cd [ -sLP ] [ arg ]
cd [ -sLP ] old new
cd [ -sLP ] {+|-}n
Change the current directory. In the first form, change the
current directory to arg, or to the value of $HOME if arg is
not specified. If arg is ‘-’, change to the value of $OLDPWD,
the previous directory. Otherwise, if a directory named arg is
not found in the current directory and arg does not begin with
a slash, search each component of the shell parameter cdpath.
If no directory is found and the option CDABLE_VARS is set, and
a parameter named arg exists whose value begins with a slash,
treat its value as the directory. In that case, the parameter
is added to the named directory hash table.
The second form of cd substitutes the string new for the string
old in the name of the current directory, and tries to change
to this new directory.
The third form of cd extracts an entry from the directory
stack, and changes to that directory. An argument of the form
‘+n’ identifies a stack entry by counting from the left of the
list shown by the dirs command, starting with zero. An argu-
ment of the form ‘-n’ counts from the right. If the
PUSHD_MINUS option is set, the meanings of ‘+’ and ‘-’ in this
context are swapped.
If the -s option is specified, cd refuses to change the current
directory if the given pathname contains symlinks. If the -P
option is given or the CHASE_LINKS option is set, symbolic
links are resolved to their true values. If the -L option is
given symbolic links are followed regardless of the state of
the CHASE_LINKS option.
chdir Same as cd.
clone See the section ‘The zsh/clone Module’ in zshmodules(1).
command [ -pvV ] simple command
The simple command argument is taken as an external command
instead of a function or builtin and is executed. If the
POSIX_BUILTINS option is set, builtins will also be executed
but certain special properties of them are suppressed. The -p
flag causes a default path to be searched instead of that in
$path. With the -v flag, command is similar to whence and with
-V, it is equivalent to whence -v.
See also the section ‘Precommand Modifiers’.
comparguments
See the section ‘The zsh/computil Module’ in zshmodules(1).
compcall
See the section ‘The zsh/compctl Module’ in zshmodules(1).
compctl
See the section ‘The zsh/compctl Module’ in zshmodules(1).
compdescribe
See the section ‘The zsh/computil Module’ in zshmodules(1).
compfiles
See the section ‘The zsh/computil Module’ in zshmodules(1).
compgroups
See the section ‘The zsh/computil Module’ in zshmodules(1).
compquote
See the section ‘The zsh/computil Module’ in zshmodules(1).
comptags
See the section ‘The zsh/computil Module’ in zshmodules(1).
comptry
See the section ‘The zsh/computil Module’ in zshmodules(1).
compvalues
See the section ‘The zsh/computil Module’ in zshmodules(1).
continue [ n ]
Resume the next iteration of the enclosing for, while, until,
select or repeat loop. If n is specified, break out of n-1
loops and resume at the nth enclosing loop.
declare
Same as typeset.
dirs [ -c ] [ arg ... ]
dirs [ -lpv ]
With no arguments, print the contents of the directory stack.
Directories are added to this stack with the pushd command, and
removed with the cd or popd commands. If arguments are speci-
fied, load them onto the directory stack, replacing anything
that was there, and push the current directory onto the stack.
-c clear the directory stack.
-l print directory names in full instead of using of using
~ expressions.
-p print directory entries one per line.
-v number the directories in the stack when printing.
disable [ -afmrs ] name ...
Temporarily disable the named hash table elements. The default
is to disable builtin commands. This allows you to use an
external command with the same name as a builtin command. The
-a option causes disable to act on regular or global aliases.
The -s option causes disable to act on suffix aliases. The -f
option causes disable to act on shell functions. The -r
options causes disable to act on reserved words. Without argu-
ments all disabled hash table elements from the corresponding
hash table are printed. With the -m flag the arguments are
taken as patterns (which should be quoted to prevent them from
undergoing filename expansion), and all hash table elements
from the corresponding hash table matching these patterns are
disabled. Disabled objects can be enabled with the enable com-
mand.
disown [ job ... ]
job ... &|
job ... &!
Remove the specified jobs from the job table; the shell will no
longer report their status, and will not complain if you try to
exit an interactive shell with them running or stopped. If no
job is specified, disown the current job.
If the jobs are currently stopped and the AUTO_CONTINUE option
is not set, a warning is printed containing information about
how to make them running after they have been disowned. If one
of the latter two forms is used, the jobs will automatically be
made running, independent of the setting of the AUTO_CONTINUE
option.
echo [ -neE ] [ arg ... ]
Write each arg on the standard output, with a space separating
each one. If the -n flag is not present, print a newline at
the end. echo recognizes the following escape sequences:
\a bell character
\b backspace
\c suppress final newline
\e escape
\f form feed
\n linefeed (newline)
\r carriage return
\t horizontal tab
\v vertical tab
\\ backslash
\0NNN character code in octal
\xNN character code in hexadecimal
\uNNNN unicode character code in hexadecimal
\UNNNNNNNN
unicode character code in hexadecimal
The -E flag, or the BSD_ECHO option, can be used to disable
these escape sequences. In the latter case, -e flag can be
used to enable them.
echotc See the section ‘The zsh/termcap Module’ in zshmodules(1).
echoti See the section ‘The zsh/terminfo Module’ in zshmodules(1).
emulate [ -LR ] {zsh|sh|ksh|csh}
Set up zsh options to emulate the specified shell as much as
possible. csh will never be fully emulated. If the argument
is not one of the shells listed above, zsh will be used as a
default; more precisely, the tests performed on the argument
are the same as those used to determine the emulation at
startup based on the shell name, see the section ‘Compatibil-
ity’ in zshmisc(1) . If the -R option is given, all options
are reset to their default value corresponding to the specified
emulation mode, except for certain options describing the
interactive environment; otherwise, only those options likely
to cause portability problems in scripts and functions are
altered. If the -L option is given, the options LOCAL_OPTIONS
and LOCAL_TRAPS will be set as well, causing the effects of the
emulate command and any setopt and trap commands to be local to
the immediately surrounding shell function, if any; normally
these options are turned off in all emulation modes except ksh.
enable [ -afmrs ] name ...
Enable the named hash table elements, presumably disabled ear-
lier with disable. The default is to enable builtin commands.
The -a option causes enable to act on regular or global
aliases. The -s option causes enable to act on suffix aliases.
The -f option causes enable to act on shell functions. The -r
option causes enable to act on reserved words. Without argu-
ments all enabled hash table elements from the corresponding
hash table are printed. With the -m flag the arguments are
taken as patterns (should be quoted) and all hash table ele-
ments from the corresponding hash table matching these patterns
are enabled. Enabled objects can be disabled with the disable
builtin command.
eval [ arg ... ]
Read the arguments as input to the shell and execute the
resulting command in the current shell process.
exec simple command
See the section ‘Precommand Modifiers’.
exit [ n ]
Exit the shell with the exit code specified by n; if none is
specified, use the exit code from the last command executed.
An EOF condition will also cause the shell to exit, unless the
IGNORE_EOF option is set.
export [ name[=value] ... ]
The specified names are marked for automatic export to the
environment of subsequently executed commands. Equivalent to
typeset -gx. If a parameter specified does not already exist,
it is created in the global scope.
false [ arg ... ]
Do nothing and return an exit code of 1.
fc [ -e ename ] [ -nlrdDfEim ] [ old=new ... ] [ first [ last ] ]
fc -ARWI [ filename ]
Select a range of commands from first to last from the history
list. The arguments first and last may be specified as a num-
ber or as a string. A negative number is used as an offset to
the current history event number. A string specifies the most
recent event beginning with the given string. All substitu-
tions old=new, if any, are then performed on the commands.
If the -l flag is given, the resulting commands are listed on
standard output. If the -m flag is also given the first argu-
ment is taken as a pattern (should be quoted) and only the his-
tory events matching this pattern will be shown. Otherwise the
editor program ename is invoked on a file containing these his-
tory events. If ename is not given, the value of the parameter
FCEDIT is used. If ename is ‘-’, no editor is invoked. When
editing is complete, the edited command is executed.
If first is not specified, it will be set to -1 (the most
recent event), or to -16 if the -l flag is given. If last is
not specified, it will be set to first, or to -1 if the -l flag
is given.
The flag -r reverses the order of the commands and the flag -n
suppresses command numbers when listing. Also when listing, -d
prints timestamps for each command, and -f prints full
time-date stamps. Adding the -E flag causes the dates to be
printed as ‘dd.mm.yyyy’, instead of the default ‘mm/dd/yyyy’.
Adding the -i flag causes the dates to be printed in ISO8601
‘yyyy-mm-dd’ format. With the -D flag, fc prints elapsed
times.
‘fc -R’ reads the history from the given file, ‘fc -W’ writes
the history out to the given file, and ‘fc -A’ appends the his-
tory out to the given file. If no filename is specified, the
$HISTFILE is assumed. If the -I option is added to -R, only
those events that are not already contained within the internal
history list are added. If the -I option is added to -A or -W,
only those events that are new since last incremental
append/write to the history file are appended/written. In any
case, the created file will have no more than $SAVEHIST
entries.
fg [ job ... ]
job ...
Bring each specified job in turn to the foreground. If no job
is specified, resume the current job.
float [ {+|-}EFHghlprtux ] [ name[=value] ... ]
Equivalent to typeset -E, except that options irrelevant to
floating point numbers are not permitted.
functions [ {+|-}UXmtu ] [ name ... ]
Equivalent to typeset -f.
getcap See the section ‘The zsh/cap Module’ in zshmodules(1).
getln [ -AclneE ] name ...
Read the top value from the buffer stack and put it in the
shell parameter name. Equivalent to read -zr.
getopts optstring name [ arg ... ]
Checks the args for legal options. If the args are omitted,
use the positional parameters. A valid option argument begins
with a ‘+’ or a ‘-’. An argument not beginning with a ‘+’ or a
‘-’, or the argument ‘--’, ends the options. Note that a sin-
gle ‘-’ is not considered a valid option argument. optstring
contains the letters that getopts recognizes. If a letter is
followed by a ‘:’, that option is expected to have an argument.
The options can be separated from the argument by blanks.
Each time it is invoked, getopts places the option letter it
finds in the shell parameter name, prepended with a ‘+’ when
arg begins with a ‘+’. The index of the next arg is stored in
OPTIND. The option argument, if any, is stored in OPTARG.
The first option to be examined may be changed by explicitly
assigning to OPTIND. OPTIND has an initial value of 1, and is
normally reset to 1 upon exit from a shell function. OPTARG is
not reset and retains its value from the most recent call to
getopts. If either of OPTIND or OPTARG is explicitly unset, it
remains unset, and the index or option argument is not stored.
The option itself is still stored in name in this case.
A leading ‘:’ in optstring causes getopts to store the letter
of any invalid option in OPTARG, and to set name to ‘?’ for an
unknown option and to ‘:’ when a required option is missing.
Otherwise, getopts sets name to ‘?’ and prints an error message
when an option is invalid. The exit status is nonzero when
there are no more options.
hash [ -Ldfmrv ] [ name[=value] ] ...
hash can be used to directly modify the contents of the command
hash table, and the named directory hash table. Normally one
would modify these tables by modifying one’s PATH (for the com-
mand hash table) or by creating appropriate shell parameters
(for the named directory hash table). The choice of hash table
to work on is determined by the -d option; without the option
the command hash table is used, and with the option the named
directory hash table is used.
Given no arguments, and neither the -r or -f options, the
selected hash table will be listed in full.
The -r option causes the selected hash table to be emptied. It
will be subsequently rebuilt in the normal fashion. The -f
option causes the selected hash table to be fully rebuilt imme-
diately. For the command hash table this hashes all the abso-
lute directories in the PATH, and for the named directory hash
table this adds all users’ home directories. These two options
cannot be used with any arguments.
The -m option causes the arguments to be taken as patterns
(which should be quoted) and the elements of the hash table
matching those patterns are printed. This is the only way to
display a limited selection of hash table elements.
For each name with a corresponding value, put ‘name’ in the
selected hash table, associating it with the pathname ‘value’.
In the command hash table, this means that whenever ‘name’ is
used as a command argument, the shell will try to execute the
file given by ‘value’. In the named directory hash table, this
means that ‘value’ may be referred to as ‘~name’.
For each name with no corresponding value, attempt to add name
to the hash table, checking what the appropriate value is in
the normal manner for that hash table. If an appropriate value
can’t be found, then the hash table will be unchanged.
The -v option causes hash table entries to be listed as they
are added by explicit specification. If has no effect if used
with -f.
If the -L flag is present, then each hash table entry is
printed in the form of a call to hash.
history
Same as fc -l.
integer [ {+|-}Hghilprtux ] [ name[=value] ... ]
Equivalent to typeset -i, except that options irrelevant to
integers are not permitted.
jobs [ -dlprs ] [ job ... ]
jobs -Z string
Lists information about each given job, or all jobs if job is
omitted. The -l flag lists process IDs, and the -p flag lists
process groups. If the -r flag is specified only running jobs
will be listed and if the -s flag is given only stopped jobs
are shown. If the -d flag is given, the directory from which
the job was started (which may not be the current directory of
the job) will also be shown.
The -Z option replaces the shell’s argument and environment
space with the given string, truncated if necessary to fit.
This will normally be visible in ps (ps(1)) listings. This
feature is typically used by daemons, to indicate their state.
kill [ -s signal_name | -n signal_number | -sig ] job ...
kill -l [ sig ... ]
Sends either SIGTERM or the specified signal to the given jobs
or processes. Signals are given by number or by names, with or
without the ‘SIG’ prefix. If the signal being sent is not
‘KILL’ or ‘CONT’, then the job will be sent a ‘CONT’ signal if
it is stopped. The argument job can be the process ID of a job
not in the job list. In the second form, kill -l, if sig is
not specified the signal names are listed. Otherwise, for each
sig that is a name, the corresponding signal number is listed.
For each sig that is a signal number or a number representing
the exit status of a process which was terminated or stopped by
a signal the name of the signal is printed.
let arg ...
Evaluate each arg as an arithmetic expression. See the section
‘Arithmetic Evaluation’ for a description of arithmetic expres-
sions. The exit status is 0 if the value of the last expres-
sion is nonzero, and 1 otherwise.
limit [ -hs ] [ resource [ limit ] ] ...
Set or display resource limits. Unless the -s flag is given,
the limit applies only the children of the shell. If -s is
given without other arguments, the resource limits of the cur-
rent shell is set to the previously set resource limits of the
children.
If limit is not specified, print the current limit placed on
resource, otherwise set the limit to the specified value. If
the -h flag is given, use hard limits instead of soft limits.
If no resource is given, print all limits.
resource can be one of:
addressspace
Maximum amount of address space used.
aiomemorylocked
Maximum amount of memory locked in RAM for AIO opera-
tions.
aiooperations
Maximum number of AIO operations.
cachedthreads
Maximum number of cached threads.
coredumpsize
Maximum size of a core dump.
cputime
Maximum CPU seconds per process.
datasize
Maximum data size (including stack) for each process.
descriptors
Maximum value for a file descriptor.
filesize
Largest single file allowed.
maxproc
Maximum number of processes.
maxpthreads
Maximum number of threads per process.
memorylocked
Maximum amount of memory locked in RAM.
memoryuse
Maximum resident set size.
resident
Maximum resident set size.
sockbufsize
Maximum size of all socket buffers.
stacksize
Maximum stack size for each process.
vmemorysize
Maximum amount of virtual memory.
Which of these resource limits are available depends on the
system. resource can be abbreviated to any unambiguous prefix.
limit is a number, with an optional scaling factor, as follows:
nh hours
nk kilobytes (default)
nm megabytes or minutes
[mm:]ss
minutes and seconds
local [ {+|-}AEFHLRUZahilprtux [n]] [ name[=value] ] ...
Same as typeset, except that the options -g, and -f are not
permitted. In this case the -x option does not force the use
of -g, i.e. exported variables will be local to functions.
log List all users currently logged in who are affected by the cur-
rent setting of the watch parameter.
logout [ n ]
Same as exit, except that it only works in a login shell.
noglob simple command
See the section ‘Precommand Modifiers’.
popd [ {+|-}n ]
Remove an entry from the directory stack, and perform a cd to
the new top directory. With no argument, the current top entry
is removed. An argument of the form ‘+n’ identifies a stack
entry by counting from the left of the list shown by the dirs
command, starting with zero. An argument of the form -n counts
from the right. If the PUSHD_MINUS option is set, the meanings
of ‘+’ and ‘-’ in this context are swapped.
print [ -abcDilmnNoOpPrsz ] [ -u n ] [ -f format ] [ -C cols ]
[ -R [ -en ]] [ arg ... ]
With the ‘-f’ option the arguments are printed as described by
printf. With no flags or with the flag ‘-’, the arguments are
printed on the standard output as described by echo, with the
following differences: the escape sequence ‘\M-x’ metafies the
character x (sets the highest bit), ‘\C-x’ produces a control
character (‘\C-@’ and ‘\C-?’ give the characters NUL and
delete), and ‘\E’ is a synonym for ‘\e’. Finally, if not in an
escape sequence, ‘\’ escapes the following character and is not
printed.
-a Print arguments with the column incrementing first.
Only useful with the -c and -C options.
-b Recognize all the escape sequences defined for the bind-
key command, see zshzle(1).
-c Print the arguments in columns. Unless -a is also
given, arguments are printed with the row incrementing
first.
-C cols
Print the arguments in cols columns. Unless -a is also
given, arguments are printed with the row incrementing
first.
-D Treat the arguments as directory names, replacing pre-
fixes with ~ expressions, as appropriate.
-i If given together with -o or -O, sorting is performed
case-independently.
-l Print the arguments separated by newlines instead of
spaces.
-m Take the first argument as a pattern (should be quoted),
and remove it from the argument list together with sub-
sequent arguments that do not match this pattern.
-n Do not add a newline to the output.
-N Print the arguments separated and terminated by nulls.
-o Print the arguments sorted in ascending order.
-O Print the arguments sorted in descending order.
-p Print the arguments to the input of the coprocess.
-P Perform prompt expansion (see zshmisc(1)).
-r Ignore the escape conventions of echo.
-R Emulate the BSD echo command, which does not process
escape sequences unless the -e flag is given. The -n
flag suppresses the trailing newline. Only the -e and
-n flags are recognized after -R; all other arguments
and options are printed.
-s Place the results in the history list instead of on the
standard output.
-u n Print the arguments to file descriptor n.
-z Push the arguments onto the editing buffer stack, sepa-
rated by spaces.
If any of ‘-m’, ‘-o’ or ‘-O’ are used in combination with ‘-f’
and there are no arguments (after the removal process in the
case of ‘-m’) then nothing is printed.
printf format [ arg ... ]
Print the arguments according to the format specification. For-
matting rules are the same as used in C. The same escape
sequences as for echo are recognised in the format. All C con-
version specifications ending in one of csdiouxXeEfgGn are han-
dled. In addition to this, ‘%b’ can be used instead of ‘%s’ to
cause escape sequences in the argument to be recognised and
‘%q’ can be used to quote the argument in such a way that
allows it to be reused as shell input. With the numeric format
specifiers, if the corresponding argument starts with a quote
character, the numeric value of the following character is used
as the number to print otherwise the argument is evaluated as
an arithmetic expression. See the section ‘Arithmetic Evalua-
tion’ for a description of arithmetic expressions. With ‘%n’,
the corresponding argument is taken as an identifier which is
created as an integer parameter.
Normally, conversion specifications are applied to each argu-
ment in order but they can explicitly specify the nth argument
is to be used by replacing ‘%’ by ‘%n$’ and ‘*’ by ‘*n$’. It
is recommended that you do not mix references of this explicit
style with the normal style and the handling of such mixed
styles may be subject to future change.
If arguments remain unused after formatting, the format string
is reused until all arguments have been consumed. With the
print builtin, this can be suppressed by using the -r option.
If more arguments are required by the format than have been
specified, the behaviour is as if zero or an empty string had
been specified as the argument.
pushd [ -sLP ] [ arg ]
pushd [ -sLP ] old new
pushd [ -sLP ] {+|-}n
Change the current directory, and push the old current direc-
tory onto the directory stack. In the first form, change the
current directory to arg. If arg is not specified, change to
the second directory on the stack (that is, exchange the top
two entries), or change to $HOME if the PUSHD_TO_HOME option is
set or if there is only one entry on the stack. Otherwise, arg
is interpreted as it would be by cd. The meaning of old and
new in the second form is also the same as for cd.
The third form of pushd changes directory by rotating the
directory list. An argument of the form ‘+n’ identifies a
stack entry by counting from the left of the list shown by the
dirs command, starting with zero. An argument of the form ‘-n’
counts from the right. If the PUSHD_MINUS option is set, the
meanings of ‘+’ and ‘-’ in this context are swapped.
If the option PUSHD_SILENT is not set, the directory stack will
be printed after a pushd is performed.
The options -s, -L and -P have the same meanings as for the cd
builtin.
pushln [ arg ... ]
Equivalent to print -nz.
pwd [ -rLP ]
Print the absolute pathname of the current working directory.
If the -r or the -P flag is specified, or the CHASE_LINKS
option is set and the -L flag is not given, the printed path
will not contain symbolic links.
r Same as fc -e -.
read [ -rszpqAclneE ] [ -t [ num ] ] [ -k [ num ] ] [ -d delim ]
[ -u n ] [ name[?prompt] ] [ name ... ]
Read one line and break it into fields using the characters in
$IFS as separators, except as noted below. The first field is
assigned to the first name, the second field to the second
name, etc., with leftover fields assigned to the last name. If
name is omitted then REPLY is used for scalars and reply for
arrays.
-r Raw mode: a ‘\’ at the end of a line does not signify
line continuation and backslashes in the line don’t
quote the following character and are not removed.
-s Don’t echo back characters if reading from the terminal.
Currently does not work with the -q option.
-q Read only one character from the terminal and set name
to ‘y’ if this character was ‘y’ or ‘Y’ and to ‘n’ oth-
erwise. With this flag set the return value is zero
only if the character was ‘y’ or ‘Y’. Note that this
always reads from the terminal, even if used with the -p
or -u or -z flags or with redirected input. This option
may also be used within zle widgets.
-k [ num ]
Read only one (or num) characters. All are assigned to
the first name, without word splitting. This flag is
ignored when -q is present. Input is read from the ter-
minal unless one of -u or -p is present. This option
may also be used within zle widgets.
-z Read one entry from the editor buffer stack and assign
it to the first name, without word splitting. Text is
pushed onto the stack with ‘print -z’ or with push-line
from the line editor (see zshzle(1)). This flag is
ignored when the -k or -q flags are present.
-e
-E The input read is printed (echoed) to the standard out-
put. If the -e flag is used, no input is assigned to
the parameters.
-A The first name is taken as the name of an array and all
words are assigned to it.
-c
-l These flags are allowed only if called inside a function
used for completion (specified with the -K flag to com-
pctl). If the -c flag is given, the words of the cur-
rent command are read. If the -l flag is given, the
whole line is assigned as a scalar. If both flags are
present, -l is used and -c is ignored.
-n Together with -c, the number of the word the cursor is
on is read. With -l, the index of the character the
cursor is on is read. Note that the command name is
word number 1, not word 0, and that when the cursor is
at the end of the line, its character index is the
length of the line plus one.
-u n Input is read from file descriptor n.
-p Input is read from the coprocess.
-d delim
Input is terminated by the first character of delim
instead of by newline.
-t [ num ]
Test if input is available before attempting to read.
If num is present, it must begin with a digit and will
be evaluated to give a number of seconds, which may be a
floating point number; in this case the read times out
if input is not available within this time. If num is
not present, it is taken to be zero, so that read
returns immediately if no input is available. If no
input is available, return status 1 and do not set any
variables.
This option is not available when reading from the edi-
tor buffer with -z, when called from within completion
with -c or -l, with -q which clears the input queue
before reading, or within zle where other mechanisms
should be used to test for input.
Note that read does not attempt to alter the input pro-
cessing mode. The default mode is canonical input, in
which an entire line is read at a time, so usually ‘read
-t’ will not read anything until an entire line has been
typed. However, when reading from the terminal with -k
input is processed one key at a time; in this case, only
availability of the first character is tested, so that
e.g. ‘read -t -k 2’ can still block on the second char-
acter. Use two instances of ‘read -t -k’ if this is not
what is wanted. If the first argument contains a ‘?’,
the remainder of this word is used as a prompt on stan-
dard error when the shell is interactive.
The value (exit status) of read is 1 when an end-of-file is
encountered, or when -c or -l is present and the command is not
called from a compctl function, or as described for -q. Other-
wise the value is 0.
The behavior of some combinations of the -k, -p, -q, -u and -z
flags is undefined. Presently -q cancels all the others, -p
cancels -u, -k cancels -z, and otherwise -z cancels both -p and
-u.
The -c or -l flags cancel any and all of -kpquz.
readonly
Same as typeset -r.
rehash Same as hash -r.
return [ n ]
Causes a shell function or . script to return to the invoking
script with the return status specified by n. If n is omitted,
the return status is that of the last command executed.
If return was executed from a trap in a TRAPNAL function, the
effect is different for zero and non-zero return status. With
zero status (or after an implicit return at the end of the
trap), the shell will return to whatever it was previously pro-
cessing; with a non-zero status, the shell will behave as
interrupted except that the return status of the trap is
retained. Note that the numeric value of the signal which
caused the trap is passed as the first argument, so the state-
ment ‘return $((128+$1))’ will return the same status as if the
signal had not been trapped.
sched See the section ‘The zsh/sched Module’ in zshmodules(1).
set [ {+|-}options | {+|-}o [ option_name ] ] ... [ {+|-}A [ name ] ]
[ arg ... ]
Set the options for the shell and/or set the positional parame-
ters, or declare and set an array. If the -s option is given,
it causes the specified arguments to be sorted before assigning
them to the positional parameters (or to the array name if -A
is used). With +s sort arguments in descending order. For the
meaning of the other flags, see zshoptions(1). Flags may be
specified by name using the -o option. If no option name is
supplied with -o, the current option states are printed. With
+o they are printed in a form that can be used as input to the
shell.
If the -A flag is specified, name is set to an array containing
the given args; if no name is specified, all arrays are printed
together with their values.
If +A is used and name is an array, the given arguments will
replace the initial elements of that array; if no name is spec-
ified, all arrays are printed without their values.
The behaviour of arguments after -A name or +A name depends on
whether the option KSH_ARRAYS is set. If it is not set, all
arguments following name are treated as values for the array,
regardless of their form. If the option is set, normal option
processing continues at that point; only regular arguments are
treated as values for the array. This means that
set -A array -x -- foo
sets array to ‘-x -- foo’ if KSH_ARRAYS is not set, but sets
the array to foo and turns on the option ‘-x’ if it is set.
If the -A flag is not present, but there are arguments beyond
the options, the positional parameters are set. If the option
list (if any) is terminated by ‘--’, and there are no further
arguments, the positional parameters will be unset.
If no arguments and no ‘--’ are given, then the names and val-
ues of all parameters are printed on the standard output. If
the only argument is ‘+’, the names of all parameters are
printed.
setcap See the section ‘The zsh/cap Module’ in zshmodules(1).
setopt [ {+|-}options | {+|-}o option_name ] [ name ... ]
Set the options for the shell. All options specified either
with flags or by name are set. If no arguments are supplied,
the names of all options currently set are printed. If the -m
flag is given the arguments are taken as patterns (which should
be quoted to protect them from filename expansion), and all
options with names matching these patterns are set.
shift [ n ] [ name ... ]
The positional parameters ${n+1} ... are renamed to $1 ...,
where n is an arithmetic expression that defaults to 1. If any
names are given then the arrays with these names are shifted
instead of the positional parameters.
source file [ arg ... ]
Same as ., except that the current directory is always searched
and is always searched first, before directories in $path.
stat See the section ‘The zsh/stat Module’ in zshmodules(1).
suspend [ -f ]
Suspend the execution of the shell (send it a SIGTSTP) until it
receives a SIGCONT. Unless the -f option is given, this will
refuse to suspend a login shell.
test [ arg ... ]
[ [ arg ... ] ]
Like the system version of test. Added for compatibility; use
conditional expressions instead (see the section ‘Conditional
Expressions’).
times Print the accumulated user and system times for the shell and
for processes run from the shell.
trap [ arg [ sig ... ] ]
arg is a series of commands (usually quoted to protect it from
immediate evaluation by the shell) to be read and executed when
the shell receives sig. Each sig can be given as a number or
as the name of a signal. If arg is ‘-’, then all traps sig are
reset to their default values. If arg is the empty string,
then this signal is ignored by the shell and by the commands it
invokes.
If sig is ZERR then arg will be executed after each command
with a nonzero exit status. If sig is DEBUG then arg will be
executed after each command. If sig is 0 or EXIT and the trap
statement is executed inside the body of a function, then the
command arg is executed after the function completes. If sig
is 0 or EXIT and the trap statement is not executed inside the
body of a function, then the command arg is executed when the
shell terminates.
The trap command with no arguments prints a list of commands
associated with each signal.
Note that traps defined with the trap builtin are slightly dif-
ferent from those defined as ‘TRAPNAL () { ... }’, as the lat-
ter have their own function environment (line numbers, local
variables, etc.) while the former use the environment of the
command in which they were called. For example,
trap ’print $LINENO’ DEBUG
will print the line number of a command executed after it has
run, while
TRAPDEBUG() { print $LINENO; }
will always print the number zero.
true [ arg ... ]
Do nothing and return an exit code of 0.
ttyctl -fu
The -f option freezes the tty, and -u unfreezes it. When the
tty is frozen, no changes made to the tty settings by external
programs will be honored by the shell, except for changes in
the size of the screen; the shell will simply reset the set-
tings to their previous values as soon as each command exits or
is suspended. Thus, stty and similar programs have no effect
when the tty is frozen. Without options it reports whether the
terminal is frozen or not.
type [ -wfpams ] name ...
Equivalent to whence -v.
typeset [ {+|-}AEFHLRUZafghilprtuxm [n]] [ name[=value] ... ]
typeset -T [ {+|-}LRUZrux ] SCALAR[=value] array [ sep ]
Set or display attributes and values for shell parameters.
A parameter is created for each name that does not already
refer to one. When inside a function, a new parameter is cre-
ated for every name (even those that already exist), and is
unset again when the function completes. See ‘Local Parame-
ters’ in zshparam(1). The same rules apply to special shell
parameters, which retain their special attributes when made
local.
For each name=value assignment, the parameter name is set to
value. Note that arrays currently cannot be assigned in type-
set expressions, only scalars and integers.
If the shell option TYPESET_SILENT is not set, for each remain-
ing name that refers to a parameter that is set, the name and
value of the parameter are printed in the form of an assign-
ment. Nothing is printed for newly-created parameters, or when
any attribute flags listed below are given along with the name.
Using ‘+’ instead of minus to introduce an attribute turns it
off.
If the -p option is given, parameters and values are printed in
the form of a typeset comand and an assignment (which will be
printed separately for arrays and associative arrays), regard-
less of other flags and options. Note that the -h flag on
parameters is respected; no value will be shown for these
parameters.
If the -T option is given, two or three arguments must be
present (an exception is that zero arguments are allowed to
show the list of parameters created in this fashion). The
first two are the name of a scalar and an array parameter (in
that order) that will be tied together in the manner of $PATH
and $path. The optional third argument is a single-character
separator which will be used to join the elements of the array
to form the scalar; if absent, a colon is used, as with $PATH.
Only the first character of the separator is significant; any
remaining characters are ignored. Only the scalar parameter
may be assigned an initial value. Both the scalar and the
array may otherwise be manipulated as normal. If one is unset,
the other will automatically be unset too. There is no way of
untying the variables without unsetting them, or converting the
type of one of them with another typeset command; +T does not
work, assigning an array to SCALAR is an error, and assigning a
scalar to array sets it to be a single-element array. Note
that both ‘typeset -xT ...’ and ‘export -T ...’ work, but only
the scalar will be marked for export. Setting the value using
the scalar version causes a split on all separators (which can-
not be quoted).
The -g (global) flag is treated specially: it means that any
resulting parameter will not be restricted to local scope.
Note that this does not necessarily mean that the parameter
will be global, as the flag will apply to any existing parame-
ter (even if unset) from an enclosing function. This flag does
not affect the parameter after creation, hence it has no effect
when listing existing parameters, nor does the flag +g have any
effect except in combination with -m (see below).
If no name is present, the names and values of all parameters
are printed. In this case the attribute flags restrict the
display to only those parameters that have the specified
attributes, and using ‘+’ rather than ‘-’ to introduce the flag
suppresses printing of the values of parameters when there is
no parameter name. Also, if the last option is the word ‘+’,
then names are printed but values are not.
If the -m flag is given the name arguments are taken as pat-
terns (which should be quoted). With no attribute flags, all
parameters (or functions with the -f flag) with matching names
are printed (the shell option TYPESET_SILENT is not used in
this case). Note that -m is ignored if no patterns are given.
If the +g flag is combined with -m, a new local parameter is
created for every matching parameter that is not already local.
Otherwise -m applies all other flags or assignments to the
existing parameters. Except when assignments are made with
name=value, using +m forces the matching parameters to be
printed, even inside a function.
If no attribute flags are given and either no -m flag is
present or the +m form was used, each parameter name printed is
preceded by a list of the attributes of that parameter (array,
association, exported, integer, readonly). If +m is used with
attribute flags, and all those flags are introduced with +, the
matching parameter names are printed but their values are not.
The following attribute flags may be specified:
-A The names refer to associative array parameters; see
‘Array Parameters’ in zshparam(1).
-L Left justify and remove leading blanks from value. If n
is nonzero, it defines the width of the field; otherwise
it is determined by the width of the value of the first
assignment. When the parameter is expanded, it is
filled on the right with blanks or truncated if neces-
sary to fit the field. Leading zeros are removed if the
-Z flag is also set.
-R Right justify and fill with leading blanks. If n is
nonzero if defines the width of the field; otherwise it
is determined by the width of the value of the first
assignment. When the parameter is expanded, the field
is left filled with blanks or truncated from the end.
-U For arrays (but not for associative arrays), keep only
the first occurrence of each duplicated value. This may
also be set for colon-separated special parameters like
PATH or FIGNORE, etc. This flag has a different meaning
when used with -f; see below.
-Z Right justify and fill with leading zeros if the first
non-blank character is a digit and the -L flag has not
been set. If n is nonzero it defines the width of the
field; otherwise it is determined by the width of the
value of the first assignment.
-a The names refer to array parameters. An array parameter
may be created this way, but it may not be assigned to
in the typeset statement. When displaying, both normal
and associative arrays are shown.
-f The names refer to functions rather than parameters. No
assignments can be made, and the only other valid flags
are -t, -u and -U. The flag -t turns on execution trac-
ing for this function. The -u and -U flags cause the
function to be marked for autoloading; -U also causes
alias expansion to be suppressed when the function is
loaded. The fpath parameter will be searched to find
the function definition when the function is first ref-
erenced; see the section ‘Functions’.
-h Hide: only useful for special parameters (those marked
‘<S>’ in the table in zshparams(1)), and for local
parameters with the same name as a special parameter,
though harmless for others. A special parameter with
this attribute will not retain its special effect when
made local. Thus after ‘typeset -h PATH’, a function
containing ‘typeset PATH’ will create an ordinary local
parameter without the usual behaviour of PATH. Alterna-
tively, the local parameter may itself be given this
attribute; hence inside a function ‘typeset -h PATH’
creates an ordinary local parameter and the special PATH
parameter is not altered in any way. It is also possi-
ble to create a local parameter using ‘typeset +h spe-
cial’, where the local copy of special will retain its
special properties regardless of having the -h
attribute. Global special parameters loaded from shell
modules (currently those in zsh/mapfile and zsh/parame-
ter) are automatically given the -h attribute to avoid
name clashes.
-H Hide value: specifies that typeset will not display the
value of the parameter when listing parameters; the dis-
play for such parameters is always as if the ‘+’ flag
had been given. Use of the parameter is in other
respects normal, and the option does not apply if the
parameter is specified by name, or by pattern with the
-m option. This is on by default for the parameters in
the zsh/parameter and zsh/mapfile modules. Note, how-
ever, that unlike the -h flag this is also useful for
non-special parameters.
-i Use an internal integer representation. If n is nonzero
it defines the output arithmetic base, otherwise it is
determined by the first assignment.
-E Use an internal double-precision floating point repre-
sentation. On output the variable will be converted to
scientific notation. If n is nonzero it defines the
number of significant figures to display; the default is
ten.
-F Use an internal double-precision floating point repre-
sentation. On output the variable will be converted to
fixed-point decimal notation. If n is nonzero it
defines the number of digits to display after the deci-
mal point; the default is ten.
-l Convert the result to lower case whenever the parameter
is expanded. The value is not converted when assigned.
-r The given names are marked readonly. Note that if name
is a special parameter, the readonly attribute can be
turned on, but cannot then be turned off.
-t Tags the named parameters. Tags have no special meaning
to the shell. This flag has a different meaning when
used with -f; see above.
-u Convert the result to upper case whenever the parameter
is expanded. The value is not converted when assigned.
This flag has a different meaning when used with -f; see
above.
-x Mark for automatic export to the environment of subse-
quently executed commands. If the option GLOBAL_EXPORT
is set, this implies the option -g, unless +g is also
explicitly given; in other words the parameter is not
made local to the enclosing function. This is for com-
patibility with previous versions of zsh.
ulimit [ -SHacdflmnpstv [ limit ] ... ]
Set or display resource limits of the shell and the processes
started by the shell. The value of limit can be a number in
the unit specified below or the value ‘unlimited’. By default,
only soft limits are manipulated. If the -H flag is given use
hard limits instead of soft limits. If the -S flag is given
together with the -H flag set both hard and soft limits. If no
options are used, the file size limit (-f) is assumed. If
limit is omitted the current value of the specified resources
are printed. When more than one resource values are printed
the limit name and unit is printed before each value.
-a Lists all of the current resource limits.
-c 512-byte blocks on the size of core dumps.
-d K-bytes on the size of the data segment.
-f 512-byte blocks on the size of files written.
-l K-bytes on the size of locked-in memory.
-m K-bytes on the size of physical memory.
-n open file descriptors.
-s K-bytes on the size of the stack.
-t CPU seconds to be used.
-u processes available to the user.
-v K-bytes on the size of virtual memory. On some systems
this refers to the limit called ‘address space’.
umask [ -S ] [ mask ]
The umask is set to mask. mask can be either an octal number
or a symbolic value as described in chmod(1). If mask is omit-
ted, the current value is printed. The -S option causes the
mask to be printed as a symbolic value. Otherwise, the mask is
printed as an octal number. Note that in the symbolic form the
permissions you specify are those which are to be allowed (not
denied) to the users specified.
unalias
Same as unhash -a.
unfunction
Same as unhash -f.
unhash [ -adfms ] name ...
Remove the element named name from an internal hash table. The
default is remove elements from the command hash table. The -a
option causes unhash to remove regular or global aliases. The
-s option causes unhash to remove suffix aliases. The -f
option causes unhash to remove shell functions. The -d options
causes unhash to remove named directories. If the -m flag is
given the arguments are taken as patterns (should be quoted)
and all elements of the corresponding hash table with matching
names will be removed.
unlimit [ -hs ] resource ...
The resource limit for each resource is set to the hard limit.
If the -h flag is given and the shell has appropriate privi-
leges, the hard resource limit for each resource is removed.
The resources of the shell process are only changed if the -s
flag is given.
unset [ -fmv ] name ...
Each named parameter is unset. Local parameters remain local
even if unset; they appear unset within scope, but the previous
value will still reappear when the scope ends.
Individual elements of associative array parameters may be
unset by using subscript syntax on name, which should be quoted
(or the entire command prefixed with noglob) to protect the
subscript from filename generation.
If the -m flag is specified the arguments are taken as patterns
(should be quoted) and all parameters with matching names are
unset. Note that this cannot be used when unsetting associa-
tive array elements, as the subscript will be treated as part
of the pattern.
The -v flag specifies that name refers to parameters. This is
the default behaviour.
unset -f is equivalent to unfunction.
unsetopt [ {+|-}options | {+|-}o option_name ] [ name ... ]
Unset the options for the shell. All options specified either
with flags or by name are unset. If no arguments are supplied,
the names of all options currently unset are printed. If the
-m flag is given the arguments are taken as patterns (which
should be quoted to preserve them from being interpreted as
glob patterns), and all options with names matching these pat-
terns are unset.
vared See the section ‘Zle Builtins’ in zshzle(1).
wait [ job ... ]
Wait for the specified jobs or processes. If job is not given
then all currently active child processes are waited for. Each
job can be either a job specification or the process ID of a
job in the job table. The exit status from this command is
that of the job waited for.
whence [ -vcwfpams ] name ...
For each name, indicate how it would be interpreted if used as
a command name.
-v Produce a more verbose report.
-c Print the results in a csh-like format. This takes
precedence over -v.
-w For each name, print ‘name: word’ where word is one of
alias, builtin, command, function, hashed, reserved or
none, according as name corresponds to an alias, a
built-in command, an external command, a shell function,
a command defined with the hash builtin, a reserved
word, or is not recognised. This takes precedence over
-v and -c.
-f Causes the contents of a shell function to be displayed,
which would otherwise not happen unless the -c flag were
used.
-p Do a path search for name even if it is an alias,
reserved word, shell function or builtin.
-a Do a search for all occurrences of name throughout the
command path. Normally only the first occurrence is
printed.
-m The arguments are taken as patterns (should be quoted),
and the information is displayed for each command match-
ing one of these patterns.
-s If a pathname contains symlinks, print the symlink-free
pathname as well.
where [ -wpms ] name ...
Equivalent to whence -ca.
which [ -wpams ] name ...
Equivalent to whence -c.
zcompile [ -U ] [ -z | -k ] [ -R | -M ] file [ name ... ]
zcompile -ca [ -m ] [ -R | -M ] file [ name ... ]
zcompile -t file [ name ... ]
This builtin command can be used to compile functions or
scripts, storing the compiled form in a file, and to examine
files containing the compiled form. This allows faster
autoloading of functions and execution of scripts by avoiding
parsing of the text when the files are read.
The first form (without the -c, -a or -t options) creates a
compiled file. If only the file argument is given, the output
file has the name ‘file.zwc’ and will be placed in the same
directory as the file. The shell will load the compiled file
instead of the normal function file when the function is
autoloaded; see the section ‘Autoloading Functions’ in zsh-
func(1) for a description of how autoloaded functions are
searched. The extension .zwc stands for ‘zsh word code’.
If there is at least one name argument, all the named files are
compiled into the output file given as the first argument. If
file does not end in .zwc, this extension is automatically
appended. Files containing multiple compiled functions are
called ‘digest’ files, and are intended to be used as elements
of the FPATH/fpath special array.
The second form, with the -c or -a options, writes the compiled
definitions for all the named functions into file. For -c, the
names must be functions currently defined in the shell, not
those marked for autoloading. Undefined functions that are
marked for autoloading may be written by using the -a option,
in which case the fpath is searched and the contents of the
definition files for those functions, if found, are compiled
into file. If both -c and -a are given, names of both defined
functions and functions marked for autoloading may be given.
In either case, the functions in files written with the -c or
-a option will be autoloaded as if the KSH_AUTOLOAD option were
unset.
The reason for handling loaded and not-yet-loaded functions
with different options is that some definition files for
autoloading define multiple functions, including the function
with the same name as the file, and, at the end, call that
function. In such cases the output of ‘zcompile -c’ does not
include the additional functions defined in the file, and any
other initialization code in the file is lost. Using ‘zcompile
-a’ captures all this extra information.
If the -m option is combined with -c or -a, the names are used
as patterns and all functions whose names match one of these
patterns will be written. If no name is given, the definitions
of all functions currently defined or marked as autoloaded will
be written.
The third form, with the -t option, examines an existing com-
piled file. Without further arguments, the names of the origi-
nal files compiled into it are listed. The first line of out-
put shows the version of the shell which compiled the file and
how the file will be used (i.e. by reading it directly or by
mapping it into memory). With arguments, nothing is output and
the return value is set to zero if definitions for all names
were found in the compiled file, and non-zero if the definition
for at least one name was not found.
Other options:
-U Aliases are not expanded when compiling the named files.
-R When the compiled file is read, its contents are copied
into the shell’s memory, rather than memory-mapped (see
-M). This happens automatically on systems that do not
support memory mapping.
When compiling scripts instead of autoloadable func-
tions, it is often desirable to use this option; other-
wise the whole file, including the code to define func-
tions which have already been defined, will remain
mapped, consequently wasting memory.
-M The compiled file is mapped into the shell’s memory when
read. This is done in such a way that multiple instances
of the shell running on the same host will share this
mapped file. If neither -R nor -M is given, the zcom-
pile builtin decides what to do based on the size of the
compiled file.
-k
-z These options are used when the compiled file contains
functions which are to be autoloaded. If -z is given,
the function will be autoloaded as if the KSH_AUTOLOAD
option is not set, even if it is set at the time the
compiled file is read, while if the -k is given, the
function will be loaded as if KSH_AUTOLOAD is set. If
neither of these options is given, the function will be
loaded as determined by the setting of the KSH_AUTOLOAD
option at the time the compiled file is read.
These options may also appear as many times as necessary
between the listed names to specify the loading style of
all following functions, up to the next -k or -z.
The created file always contains two versions of the
compiled format, one for big-endian machines and one for
small-endian machines. The upshot of this is that the
compiled file is machine independent and if it is read
or mapped, only one half of the file is actually used
(and mapped).
zformat
See the section ‘The zsh/zutil Module’ in zshmodules(1).
zftp See the section ‘The zsh/zftp Module’ in zshmodules(1).
zle See the section ‘Zle Builtins’ in zshzle(1).
zmodload [ -dL ] [ ... ]
zmodload -e [ -A ] [ ... ]
zmodload [ -a [ -bcpf [ -I ] ] ] [ -iL ] ...
zmodload -u [ -abcdpf [ -I ] ] [ -iL ] ...
zmodload -A [ -L ] [ modalias[=module] ... ]
zmodload -R modalias ...
Performs operations relating to zsh’s loadable modules. Load-
ing of modules while the shell is running (‘dynamical loading’)
is not available on all operating systems, or on all installa-
tions on a particular operating system, although the zmodload
command itself is always available and can be used to manipu-
late modules built into versions of the shell executable with-
out dynamical loading.
Without arguments the names of all currently loaded binary mod-
ules are printed. The -L option causes this list to be in the
form of a series of zmodload commands. Forms with arguments
are:
zmodload [ -i ] name ...
zmodload -u [ -i ] name ...
In the simplest case, zmodload loads a binary module.
The module must be in a file with a name consisting of
the specified name followed by a standard suffix, usu-
ally ‘.so’ (‘.sl’ on HPUX). If the module to be loaded
is already loaded and the -i option is given, the dupli-
cate module is ignored. Otherwise zmodload prints an
error message.
The named module is searched for in the same way a com-
mand is, using $module_path instead of $path. However,
the path search is performed even when the module name
contains a ‘/’, which it usually does. There is no way
to prevent the path search.
With -u, zmodload unloads modules. The same name must
be given that was given when the module was loaded, but
it is not necessary for the module to exist in the
filesystem. The -i option suppresses the error if the
module is already unloaded (or was never loaded).
Each module has a boot and a cleanup function. The mod-
ule will not be loaded if its boot function fails. Sim-
ilarly a module can only be unloaded if its cleanup
function runs successfully.
zmodload -d [ -L ] [ name ]
zmodload -d name dep ...
zmodload -ud name [ dep ... ]
The -d option can be used to specify module dependen-
cies. The modules named in the second and subsequent
arguments will be loaded before the module named in the
first argument.
With -d and one argument, all dependencies for that mod-
ule are listed. With -d and no arguments, all module
dependencies are listed. This listing is by default in
a Makefile-like format. The -L option changes this for-
mat to a list of zmodload -d commands.
If -d and -u are both used, dependencies are removed.
If only one argument is given, all dependencies for that
module are removed.
zmodload -ab [ -L ]
zmodload -ab [ -i ] name [ builtin ... ]
zmodload -ub [ -i ] builtin ...
The -ab option defines autoloaded builtins. It defines
the specified builtins. When any of those builtins is
called, the module specified in the first argument is
loaded. If only the name is given, one builtin is
defined, with the same name as the module. -i sup-
presses the error if the builtin is already defined or
autoloaded, regardless of which module it came from.
With -ab and no arguments, all autoloaded builtins are
listed, with the module name (if different) shown in
parentheses after the builtin name. The -L option
changes this format to a list of zmodload -a commands.
If -b is used together with the -u option, it removes
builtins previously defined with -ab. This is only pos-
sible if the builtin is not yet loaded. -i suppresses
the error if the builtin is already removed (or never
existed).
zmodload -ac [ -IL ]
zmodload -ac [ -iI ] name [ cond ... ]
zmodload -uc [ -iI ] cond ...
The -ac option is used to define autoloaded condition
codes. The cond strings give the names of the conditions
defined by the module. The optional -I option is used to
define infix condition names. Without this option prefix
condition names are defined.
If given no condition names, all defined names are
listed (as a series of zmodload commands if the -L
option is given).
The -uc option removes definitions for autoloaded condi-
tions.
zmodload -ap [ -L ]
zmodload -ap [ -i ] name [ parameter ... ]
zmodload -up [ -i ] parameter ...
The -p option is like the -b and -c options, but makes
zmodload work on autoloaded parameters instead.
zmodload -af [ -L ]
zmodload -af [ -i ] name [ function ... ]
zmodload -uf [ -i ] function ...
The -f option is like the -b, -p, and -c options, but
makes zmodload work on autoloaded math functions
instead.
zmodload -a [ -L ]
zmodload -a [ -i ] name [ builtin ... ]
zmodload -ua [ -i ] builtin ...
Equivalent to -ab and -ub.
zmodload -e [ -A ] [ string ... ]
The -e option without arguments lists all loaded mod-
ules; if the -A option is also given, module aliases
corresponding to loaded modules are also shown. With
arguments only the return status is set to zero if all
strings given as arguments are names of loaded modules
and to one if at least on string is not the name of a
loaded module. This can be used to test for the avail-
ability of things implemented by modules. In this case,
any aliases are automatically resolved and the -A flag
is not used.
zmodload -A [ -L ] [ modalias[=module] ... ]
For each argument, if both modalias and module are
given, define modalias to be an alias for the module
module. If the module modalias is ever subsequently
requested, either via a call to zmodload or implicitly,
the shell will attempt to load module instead. If mod-
ule is not given, show the definition of modalias. If
no arguments are given, list all defined module aliases.
When listing, if the -L flag was also given, list the
definition as a zmodload command to recreate the alias.
The existence of aliases for modules is completely inde-
pendent of whether the name resolved is actually loaded
as a module: while the alias exists, loading and unload-
ing the module under any alias has exactly the same
effect as using the resolved name, and does not affect
the connection between the alias and the resolved name
which can be removed either by zmodload -R or by
redefining the alias. Chains of aliases (i.e. where the
first resolved name is itself an alias) are valid so
long as these are not circular. As the aliases take the
same format as module names, they may include path sepa-
rators: in this case, there is no requirement for any
part of the path named to exist as the alias will be
resolved first. For example, ‘any/old/alias’ is always
a valid alias.
Dependencies added to aliased modules are actually added
to the resolved module; these remain if the alias is
removed. It is valid to create an alias whose name is
one of the standard shell modules and which resolves to
a different module. However, if a module has dependen-
cies, it will not be possible to use the module name as
an alias as the module will already be marked as a load-
able module in its own right.
Apart from the above, aliases can be used in the zmod-
load command anywhere module names are required. How-
ever, aliases will not be shown in lists of loaded mod-
ules with a bare ‘zmodload’.
zmodload -R modalias ...
For each modalias argument that was previously defined
as a module alias via zmodload -A, delete the alias. If
any was not defined, an error is caused and the remain-
der of the line is ignored.
Note that zsh makes no distinction between modules that were
linked into the shell and modules that are loaded dynamically.
In both cases this builtin command has to be used to make
available the builtins and other things defined by modules
(unless the module is autoloaded on these definitions). This is
true even for systems that don’t support dynamic loading of
modules.
zparseopts
See the section ‘The zsh/zutil Module’ in zshmodules(1).
zprof See the section ‘The zsh/zprof Module’ in zshmodules(1).
zpty See the section ‘The zsh/zpty Module’ in zshmodules(1).
zregexparse
See the section ‘The zsh/zutil Module’ in zshmodules(1).
zsocket
See the section ‘The zsh/net/socket Module’ in zshmodules(1).
zstyle See the section ‘The zsh/zutil Module’ in zshmodules(1).
ZSHZLE(1) ZSHZLE(1)
ztcp See the section ‘The zsh/net/tcp Module’ in zshmodules(1).
NAME
zshzle - zsh command line editor
DESCRIPTION
If the ZLE option is set (which it is by default in interactive
shells) and the shell input is attached to the terminal, the user is
able to edit command lines.
There are two display modes. The first, multiline mode, is the
default. It only works if the TERM parameter is set to a valid termi-
nal type that can move the cursor up. The second, single line mode,
is used if TERM is invalid or incapable of moving the cursor up, or if
the SINGLE_LINE_ZLE option is set. This mode is similar to ksh, and
uses no termcap sequences. If TERM is "emacs", the ZLE option will be
unset by default.
The parameters BAUD, COLUMNS, and LINES are also used by the line edi-
tor. See Parameters Used By The Shell in zshparam(1).
KEYMAPS
A keymap in ZLE contains a set of bindings between key sequences and
ZLE commands. The empty key sequence cannot be bound.
There can be any number of keymaps at any time, and each keymap has
one or more names. If all of a keymap’s names are deleted, it disap-
pears. bindkey can be used to manipulate keymap names.
Initially, there are four keymaps:
emacs EMACS emulation
viins vi emulation - insert mode
vicmd vi emulation - command mode
.safe fallback keymap
The ‘.safe’ keymap is special. It can never be altered, and the name
can never be removed. However, it can be linked to other names, which
can be removed. In the future other special keymaps may be added;
users should avoid using names beginning with ‘.’ for their own
keymaps.
In addition to these four names, either ‘emacs’ or ‘viins’ is also
linked to the name ‘main’. If one of the VISUAL or EDITOR environment
variables contain the string ‘vi’ when the shell starts up then it
will be ‘viins’, otherwise it will be ‘emacs’. bindkey’s -e and -v
options provide a convenient way to override this default choice.
When the editor starts up, it will select the ‘main’ keymap. If that
keymap doesn’t exist, it will use ‘.safe’ instead.
In the ‘.safe’ keymap, each single key is bound to self-insert, except
for ^J (line feed) and ^M (return) which are bound to accept-line.
This is deliberately not pleasant to use; if you are using it, it
means you deleted the main keymap, and you should put it back.
Reading Commands
When ZLE is reading a command from the terminal, it may read a
sequence that is bound to some command and is also a prefix of a
longer bound string. In this case ZLE will wait a certain time to see
if more characters are typed, and if not (or they don’t match any
longer string) it will execute the binding. This timeout is defined
by the KEYTIMEOUT parameter; its default is 0.4 sec. There is no
timeout if the prefix string is not itself bound to a command.
As well as ZLE commands, key sequences can be bound to other strings,
by using ‘bindkey -s’. When such a sequence is read, the replacement
string is pushed back as input, and the command reading process starts
again using these fake keystrokes. This input can itself invoke fur-
ther replacement strings, but in order to detect loops the process
will be stopped if there are twenty such replacements without a real
command being read.
ZLE BUILTINS
The ZLE module contains three related builtin commands. The bindkey
command manipulates keymaps and key bindings; the vared command
invokes ZLE on the value of a shell parameter; and the zle command
manipulates editing widgets and allows command line access to ZLE com-
mands from within shell functions.
bindkey [ options ] -l
bindkey [ options ] -d
bindkey [ options ] -D keymap ...
bindkey [ options ] -A old-keymap new-keymap
bindkey [ options ] -N new-keymap [ old-keymap ]
bindkey [ options ] -m
bindkey [ options ] -r in-string ...
bindkey [ options ] -s in-string out-string ...
bindkey [ options ] in-string command ...
bindkey [ options ] [ in-string ]
bindkey’s options can be divided into three categories: keymap
selection, operation selection, and others. The keymap selec-
tion options are:
-e Selects keymap ‘emacs’, and also links it to ‘main’.
-v Selects keymap ‘viins’, and also links it to ‘main’.
-a Selects keymap ‘vicmd’.
-M keymap
The keymap specifies a keymap name.
If a keymap selection is required and none of the options above
are used, the ‘main’ keymap is used. Some operations do not
permit a keymap to be selected, namely:
-l List all existing keymap names. If the -L option is
also used, list in the form of bindkey commands to cre-
ate the keymaps.
-d Delete all existing keymaps and reset to the default
state.
-D keymap ...
Delete the named keymaps.
-A old-keymap new-keymap
Make the new-keymap name an alias for old-keymap, so
that both names refer to the same keymap. The names
have equal standing; if either is deleted, the other
remains. If there is already a keymap with the
new-keymap name, it is deleted.
-N new-keymap [ old-keymap ]
Create a new keymap, named new-keymap. If a keymap
already has that name, it is deleted. If an old-keymap
name is given, the new keymap is initialized to be a
duplicate of it, otherwise the new keymap will be empty.
To use a newly created keymap, it should be linked to main.
Hence the sequence of commands to create and use a new keymap
‘mymap’ initialized from the emacs keymap (which remains
unchanged) is:
bindkey -N mymap emacs
bindkey -A mymap main
Note that while ‘bindkey -A newmap main’ will work when newmap
is emacs or viins, it will not work for vicmd, as switching
from vi insert to command mode becomes impossible.
The following operations act on the ‘main’ keymap if no keymap
selection option was given:
-m Add the built-in set of meta-key bindings to the
selected keymap. Only keys that are unbound or bound to
self-insert are affected.
-r in-string ...
Unbind the specified in-strings in the selected keymap.
This is exactly equivalent to binding the strings to
undefined-key.
When -R is also used, interpret the in-strings as
ranges.
When -p is also used, the in-strings specify prefixes.
Any binding that has the given in-string as a prefix,
not including the binding for the in-string itself, if
any, will be removed. For example,
bindkey -rpM viins ’^[’
will remove all bindings in the vi-insert keymap begin-
ning with an escape character (probably cursor keys),
but leave the binding for the escape character itself
(probably vi-cmd-mode). This is incompatible with the
option -R.
-s in-string out-string ...
Bind each in-string to each out-string. When in-string
is typed, out-string will be pushed back and treated as
input to the line editor. When -R is also used, inter-
pret the in-strings as ranges.
in-string command ...
Bind each in-string to each command. When -R is used,
interpret the in-strings as ranges.
[ in-string ]
List key bindings. If an in-string is specified, the
binding of that string in the selected keymap is dis-
played. Otherwise, all key bindings in the selected
keymap are displayed. (As a special case, if the -e or
-v option is used alone, the keymap is not displayed -
the implicit linking of keymaps is the only thing that
happens.)
When the option -p is used, the in-string must be
present. The listing shows all bindings which have the
given key sequence as a prefix, not including any bind-
ings for the key sequence itself.
When the -L option is used, the list is in the form of
bindkey commands to create the key bindings.
When the -R option is used as noted above, a valid range consists of
two characters, with an optional ‘-’ between them. All characters
between the two specified, inclusive, are bound as specified.
For either in-string or out-string, the following escape sequences are
recognised:
\a bell character
\b backspace
\e, \E escape
\f form feed
\n linefeed (newline)
\r carriage return
\t horizontal tab
\v vertical tab
\NNN character code in octal
\xNN character code in hexadecimal
\M[-]X character with meta bit set
\C[-]X control character
^X control character
In all other cases, ‘\’ escapes the following character. Delete is
written as ‘^?’. Note that ‘\M^?’ and ‘^\M?’ are not the same, and
that (unlike emacs), the bindings ‘\M-X’ and ‘\eX’ are entirely dis-
tinct, although they are initialized to the same bindings by ‘bindkey
-m’.
vared [ -Aache ] [ -p prompt ] [ -r rprompt ] name
The value of the parameter name is loaded into the edit buffer,
and the line editor is invoked. When the editor exits, name is
set to the string value returned by the editor. When the -c
flag is given, the parameter is created if it doesn’t already
exist. The -a flag may be given with -c to create an array
parameter, or the -A flag to create an associative array. If
the type of an existing parameter does not match the type to be
created, the parameter is unset and recreated.
If an array or array slice is being edited, separator charac-
ters as defined in $IFS will be shown quoted with a backslash,
as will backslashes themselves. Conversely, when the edited
text is split into an array, a backslash quotes an immediately
following separator character or backslash; no other special
handling of backslashes, or any handling of quotes, is per-
formed.
Individual elements of existing array or associative array
parameters may be edited by using subscript syntax on name.
New elements are created automatically, even without -c.
If the -p flag is given, the following string will be taken as
the prompt to display at the left. If the -r flag is given,
the following string gives the prompt to display at the right.
If the -h flag is specified, the history can be accessed from
ZLE. If the -e flag is given, typing ^D (Control-D) on an empty
line causes vared to exit immediately with a non-zero return
value.
zle -l [ -L | -a ] [ string ... ]
zle -D widget ...
zle -A old-widget new-widget
zle -N widget [ function ]
zle -C widget completion-widget function
zle -R [ -c ] [ display-string ] [ string ... ]
zle -M string
zle -U string
zle -K keymap
zle -F [ -L ] [ fd [ handler ] ]
zle -I
zle widget [ -n num ] [ -N ] args ...
zle The zle builtin performs a number of different actions concern-
ing ZLE. Which operation it performs depends on its options:
-l [ -L | -a ]
List all existing user-defined widgets. If the -L
option is used, list in the form of zle commands to cre-
ate the widgets.
When combined with the -a option, all widget names are
listed, including the builtin ones. In this case the -L
option is ignored.
If at least one string is given, nothing will be printed
but the return status will be zero if all strings are
names of existing widgets (or of user-defined widgets if
the -a flag is not given) and non-zero if at least one
string is not a name of an defined widget.
-D widget ...
Delete the named widgets.
-A old-widget new-widget
Make the new-widget name an alias for old-widget, so
that both names refer to the same widget. The names
have equal standing; if either is deleted, the other
remains. If there is already a widget with the new-wid-
get name, it is deleted.
-N widget [ function ]
Create a user-defined widget. If there is already a
widget with the specified name, it is overwritten. When
the new widget is invoked from within the editor, the
specified shell function is called. If no function name
is specified, it defaults to the same name as the wid-
get. For further information, see the section Widgets
in zshzle(1).
-C widget completion-widget function
Create a user-defined completion widget named widget.
The completion widget will behave like the built-in com-
pletion-widget whose name is given as completion-widget.
To generate the completions, the shell function function
will be called. For further information, see zshcomp-
wid(1).
-R [ -c ] [ display-string ] [ string ... ]
Redisplay the command line; this is to be called from
within a user-defined widget to allow changes to become
visible. If a display-string is given and not empty,
this is shown in the status line (immediately below the
line being edited).
If the optional strings are given they are listed below
the prompt in the same way as completion lists are
printed. If no strings are given but the -c option is
used such a list is cleared.
Note that this option is only useful for widgets that do
not exit immediately after using it because the strings
displayed will be erased immediately after return from
the widget.
This command can safely be called outside user defined
widgets; if zle is active, the display will be
refreshed, while if zle is not active, the command has
no effect. In this case there will usually be no other
arguments. The status is zero if zle was active, else
one.
-M string
As with the -R option, the string will be displayed
below the command line; unlike the -R option, the string
will not be put into the status line but will instead be
printed normally below the prompt. This means that the
string will still be displayed after the widget returns
(until it is overwritten by subsequent commands).
-U string
This pushes the characters in the string onto the input
stack of ZLE. After the widget currently executed fin-
ishes ZLE will behave as if the characters in the string
were typed by the user.
As ZLE uses a stack, if this option is used repeatedly
the last string pushed onto the stack will be processed
first. However, the characters in each string will be
processed in the order in which they appear in the
string.
-K keymap
Selects the keymap named keymap. An error message will
be displayed if there is no such keymap.
This keymap selection affects the interpretation of fol-
lowing keystrokes within this invocation of ZLE. Any
following invocation (e.g., the next command line) will
start as usual with the ‘main’ keymap selected.
-F [ -L ] [ fd [ handler ] ]
Only available if your system supports one of the ‘poll’
or ‘select’ system calls; most modern systems do.
Installs handler (the name of a shell function) to han-
dle input from file descriptor fd. When zle is attempt-
ing to read data, it will examine both the terminal and
the list of handled fd’s. If data becomes available on
a handled fd, zle will call handler with the fd which is
ready for reading as the only argument. If the handler
produces output to the terminal, it should call ‘zle -I’
before doing so (see below). The handler should not
attempt to read from the terminal. Note that zle makes
no attempt to check whether this fd is actually readable
when installing the handler. The user must make their
own arrangements for handling the file descriptor when
zle is not active.
Any number of handlers for any number of readable file
descriptors may be installed. Installing a handler for
an fd which is already handled causes the existing han-
dler to be replaced.
If no handler is given, but an fd is present, any han-
dler for that fd is removed. If there is none, an error
message is printed and status 1 is returned.
If no arguments are given, or the -L option is supplied,
a list of handlers is printed in a form which can be
stored for later execution.
An fd (but not a handler) may optionally be given with
the -L option; in this case, the function will list the
handler if any, else silently return status 1.
Note that this feature should be used with care. Activ-
ity on one of the fd’s which is not properly handled can
cause the terminal to become unusable.
Here is a simple example of using this feature. A con-
nection to a remote TCP port is created using the ztcp
command; see the description of the zsh/net/tcp module
in zshmodules(1). Then a handler is installed which
simply prints out any data which arrives on this connec-
tion. Note that ‘select’ will indicate that the file
descriptor needs handling if the remote side has closed
the connection; we handle that by testing for a failed
read.
if ztcp pwspc 2811; then
tcpfd=$REPLY
handler() {
zle -I
local line
if ! read -r line <&$1; then
# select marks this fd if we reach EOF,
# so handle this specially.
print "[Read on fd $1 failed, removing.]" >&2
zle -F $1
return 1
fi
print -r - $line
}
zle -F $tcpfd handler
fi
-I Unusually, this option is most useful outside ordinary
widget functions, though it may be used within if normal
output to the terminal is required. It invalidates the
current zle display in preparation for output; typically
this will be from a trap function. It has no effect if
zle is not active. When a trap exits, the shell checks
to see if the display needs restoring, hence the follow-
ing will print output in such a way as not to disturb
the line being edited:
TRAPUSR1() {
# Invalidate zle display
[[ -o zle ]] && zle -I
# Show output
print Hello
}
In general, the trap function may need to test whether
zle is active before using this method (as shown in the
example), since the zsh/zle module may not even be
loaded; if it is not, the command can be skipped.
It is possible to call ‘zle -I’ several times before
control is returned to the editor; the display will only
be invalidated the first time to minimise disruption.
Note that there are normally better ways of manipulating
the display from within zle widgets; see, for example,
‘zle -R’ above.
The status is zero if zle is active and the current zle
display has been invalidated (even if this was by a pre-
vious call to ‘zle -I’), else one.
widget [ -n num ] [ -N ] args ...
Invoke the specified widget. This can only be done when
ZLE is active; normally this will be within a
user-defined widget.
With the options -n and -N, the current numerical argu-
ment will be saved and then restored after the call to
widget; ‘-n num’ sets the numerical argument temporarily
to num, while ‘-N’ sets it to the default, i.e. as if
there were none.
Any further arguments will be passed to the widget. If
it is a shell function, these are passed down as posi-
tional parameters; for builtin widgets it is up to the
widget in question what it does with them. Currently
arguments are only handled by the incremental-search
commands, the history-search-forward and -backward and
the corresponding functions prefixed by vi-, and by uni-
versal-argument. No error is flagged if the command
does not use the arguments, or only uses some of them.
The return status reflects the success or failure of the
operation carried out by the widget, or if it is a
user-defined widget the return status of the shell func-
tion.
A non-zero return status causes the shell to beep when
the widget exits, unless the BEEP options was unset or
the widget was called via the zle command. Thus if a
user defined widget requires an immediate beep, it
should call the beep widget directly.
With no options and no arguments, only the return status will be set.
It is zero if ZLE is currently active and widgets could be invoked
using this builtin command and non-zero if ZLE is not active.
WIDGETS
All actions in the editor are performed by ‘widgets’. A widget’s job
is simply to perform some small action. The ZLE commands that key
sequences in keymaps are bound to are in fact widgets. Widgets can be
user-defined or built in.
The standard widgets built in to ZLE are listed in Standard Widgets
below. Other built-in widgets can be defined by other modules (see
zshmodules(1)). Each built-in widget has two names: its normal canon-
ical name, and the same name preceded by a ‘.’. The ‘.’ name is spe-
cial: it can’t be rebound to a different widget. This makes the wid-
get available even when its usual name has been redefined.
User-defined widgets are defined using ‘zle -N’, and implemented as
shell functions. When the widget is executed, the corresponding shell
function is executed, and can perform editing (or other) actions. It
is recommended that user-defined widgets should not have names start-
ing with ‘.’.
USER-DEFINED WIDGETS
User-defined widgets, being implemented as shell functions, can exe-
cute any normal shell command. They can also run other widgets
(whether built-in or user-defined) using the zle builtin command. The
standard input of the function is closed to prevent external commands
from unintentionally blocking ZLE by reading from the terminal, but
read -k or read -q can be used to read characters. Finally, they can
examine and edit the ZLE buffer being edited by reading and setting
the special parameters described below.
These special parameters are always available in widget functions, but
are not in any way special outside ZLE. If they have some normal
value outside ZLE, that value is temporarily inaccessible, but will
return when the widget function exits. These special parameters in
fact have local scope, like parameters created in a function using
local.
Inside completion widgets and traps called while ZLE is active, these
parameters are available read-only.
BUFFER (scalar)
The entire contents of the edit buffer. If it is written to,
the cursor remains at the same offset, unless that would put it
outside the buffer.
BUFFERLINES (integer)
The number of screen lines needed for the edit buffer currently
displayed on screen (i.e. without any changes to the preceding
parameters done after the last redisplay); read-only.
CONTEXT (scalar)
The context in which zle was called to read a line; read-only.
One of the values:
start The start of a command line (at prompt PS1).
cont A continuation to a command line (at prompt PS2).
select In a select loop.
vared Editing a variable in vared.
CURSOR (integer)
The offset of the cursor, within the edit buffer. This is in
the range 0 to $#BUFFER, and is by definition equal to
$#LBUFFER. Attempts to move the cursor outside the buffer will
result in the cursor being moved to the appropriate end of the
buffer.
CUTBUFFER (scalar)
The last item to be cut using one of the ‘kill-’ commands; the
string which the next yank would insert in the line.
HISTNO (integer)
The current history number; read-only.
KEYMAP (scalar)
The name of the currently selected keymap; read-only.
KEYS (scalar)
The keys typed to invoke this widget, as a literal string;
read-only.
killring (array)
The array of previously killed items, with the most recently
killed first. This gives the items that would be retrieved by
a yank-pop in the same order.
The default size for the kill ring is eight, however the length
may be changed by normal array operations. Any empty string in
the kill ring is ignored by the yank-pop command, hence the
size of the array effectively sets the maximum length of the
kill ring, while the number of non-zero strings gives the cur-
rent length, both as seen by the user at the command line.
LASTSEARCH (scalar)
The last search string used by an interactive search ;
read-only.
LASTWIDGET (scalar)
The name of the last widget that was executed; read-only.
LBUFFER (scalar)
The part of the buffer that lies to the left of the cursor
position. If it is assigned to, only that part of the buffer
is replaced, and the cursor remains between the new $LBUFFER
and the old $RBUFFER.
MARK (integer)
Like CURSOR, but for the mark.
NUMERIC (integer)
The numeric argument. If no numeric argument was given, this
parameter is unset. When this is set inside a widget function,
builtin widgets called with the zle builtin command will use
the value assigned. If it is unset inside a widget function,
builtin widgets called behave as if no numeric argument was
given.
PENDING (integer)
The number of bytes pending for input, i.e. the number of bytes
which have already been typed and can immediately be read. On
systems where the shell is not able to get this information,
this parameter will always have a value of zero. Read-only.
PREBUFFER (scalar)
In a multi-line input at the secondary prompt, this read-only
parameter contains the contents of the lines before the one the
cursor is currently in.
PREDISPLAY (scalar)
Text to be displayed before the start of the editable text
buffer. This does not have to be a complete line; to display a
complete line, a newline must be appended explicitly. The
text is reset on each new invocation (but not recursive invoca-
tion) of zle.
POSTDISPLAY (scalar)
Text to be displayed after the end of the editable text buffer.
This does not have to be a complete line; to display a complete
line, a newline must be prepended explicitly. The text is
reset on each new invocation (but not recursive invocation) of
zle.
RBUFFER (scalar)
The part of the buffer that lies to the right of the cursor
position. If it is assigned to, only that part of the buffer
is replaced, and the cursor remains between the old $LBUFFER
and the new $RBUFFER.
WIDGET (scalar)
The name of the widget currently being executed; read-only.
Special Widget
There is one user-defined widget which is special to the shell. If it
does not exist, no special action is taken. The environment provided
is identical to that for any other editing widget.
zle-line-init
Executed every time the line editor is started to read a new
line of input. The following example puts the line editor into
vi command mode when it starts up.
zle-line-init() { zle -K vicmd; }
zle -N zle-line-init
(The command inside the function sets the keymap directly; it
is equivalent to zle vi-cmd-mode.)
STANDARD WIDGETS
The following is a list of all the standard widgets, and their default
bindings in emacs mode, vi command mode and vi insert mode (the
‘emacs’, ‘vicmd’ and ‘viins’ keymaps, respectively).
Note that cursor keys are bound to movement keys in all three keymaps;
the shell assumes that the cursor keys send the key sequences reported
by the terminal-handling library (termcap or terminfo). The key
sequences shown in the list are those based on the VT100, common on
many modern terminals, but in fact these are not necessarily bound.
In the case of the viins keymap, the initial escape character of the
sequences serves also to return to the vicmd keymap: whether this hap-
pens is determined by the KEYTIMEOUT parameter, see zshparam(1).
Movement
vi-backward-blank-word (unbound) (B) (unbound)
Move backward one word, where a word is defined as a series of
non-blank characters.
backward-char (^B ESC-[D) (unbound) (unbound)
Move backward one character.
vi-backward-char (unbound) (^H h ^?) (ESC-[D)
Move backward one character, without changing lines.
backward-word (ESC-B ESC-b) (unbound) (unbound)
Move to the beginning of the previous word.
emacs-backward-word
Move to the beginning of the previous word.
vi-backward-word (unbound) (b) (unbound)
Move to the beginning of the previous word, vi-style.
beginning-of-line (^A) (unbound) (unbound)
Move to the beginning of the line. If already at the beginning
of the line, move to the beginning of the previous line, if
any.
vi-beginning-of-line
Move to the beginning of the line, without changing lines.
end-of-line (^E) (unbound) (unbound)
Move to the end of the line. If already at the end of the
line, move to the end of the next line, if any.
vi-end-of-line (unbound) ($) (unbound)
Move to the end of the line. If an argument is given to this
command, the cursor will be moved to the end of the line (argu-
ment - 1) lines down.
vi-forward-blank-word (unbound) (W) (unbound)
Move forward one word, where a word is defined as a series of
non-blank characters.
vi-forward-blank-word-end (unbound) (E) (unbound)
Move to the end of the current word, or, if at the end of the
current word, to the end of the next word, where a word is
defined as a series of non-blank characters.
forward-char (^F ESC-[C) (unbound) (unbound)
Move forward one character.
vi-forward-char (unbound) (space l) (ESC-[C)
Move forward one character.
vi-find-next-char (^X^F) (f) (unbound)
Read a character from the keyboard, and move to the next occur-
rence of it in the line.
vi-find-next-char-skip (unbound) (t) (unbound)
Read a character from the keyboard, and move to the position
just before the next occurrence of it in the line.
vi-find-prev-char (unbound) (F) (unbound)
Read a character from the keyboard, and move to the previous
occurrence of it in the line.
vi-find-prev-char-skip (unbound) (T) (unbound)
Read a character from the keyboard, and move to the position
just after the previous occurrence of it in the line.
vi-first-non-blank (unbound) (^) (unbound)
Move to the first non-blank character in the line.
vi-forward-word (unbound) (w) (unbound)
Move forward one word, vi-style.
forward-word (ESC-F ESC-f) (unbound) (unbound)
Move to the beginning of the next word. The editor’s idea of a
word is specified with the WORDCHARS parameter.
emacs-forward-word
Move to the end of the next word.
vi-forward-word-end (unbound) (e) (unbound)
Move to the end of the next word.
vi-goto-column (ESC-|) (|) (unbound)
Move to the column specified by the numeric argument.
vi-goto-mark (unbound) (‘) (unbound)
Move to the specified mark.
vi-goto-mark-line (unbound) (’) (unbound)
Move to beginning of the line containing the specified mark.
vi-repeat-find (unbound) (;) (unbound)
Repeat the last vi-find command.
vi-rev-repeat-find (unbound) (,) (unbound)
Repeat the last vi-find command in the opposite direction.
History Control
beginning-of-buffer-or-history (ESC-<) (unbound) (unbound)
Move to the beginning of the buffer, or if already there, move
to the first event in the history list.
beginning-of-line-hist
Move to the beginning of the line. If already at the beginning
of the buffer, move to the previous history line.
beginning-of-history
Move to the first event in the history list.
down-line-or-history (^N ESC-[B) (j) (ESC-[B)
Move down a line in the buffer, or if already at the bottom
line, move to the next event in the history list.
vi-down-line-or-history (unbound) (+) (unbound)
Move down a line in the buffer, or if already at the bottom
line, move to the next event in the history list. Then move to
the first non-blank character on the line.
down-line-or-search
Move down a line in the buffer, or if already at the bottom
line, search forward in the history for a line beginning with
the first word in the buffer.
If called from a function by the zle command with arguments,
the first argument is taken as the string for which to search,
rather than the first word in the buffer.
down-history (unbound) (^N) (unbound)
Move to the next event in the history list.
history-beginning-search-backward
Search backward in the history for a line beginning with the
current line up to the cursor. This leaves the cursor in its
original position.
end-of-buffer-or-history (ESC->) (unbound) (unbound)
Move to the end of the buffer, or if already there, move to the
last event in the history list.
end-of-line-hist
Move to the end of the line. If already at the end of the
buffer, move to the next history line.
end-of-history
Move to the last event in the history list.
vi-fetch-history (unbound) (G) (unbound)
Fetch the history line specified by the numeric argument. This
defaults to the current history line (i.e. the one that isn’t
history yet).
history-incremental-search-backward (^R ^Xr) (unbound) (unbound)
Search backward incrementally for a specified string. The
search is case-insensitive if the search string does not have
uppercase letters and no numeric argument was given. The
string may begin with ‘^’ to anchor the search to the beginning
of the line.
A restricted set of editing functions is available in the
mini-buffer. An interrupt signal, as defined by the stty set-
ting, will stop the search and go back to the original line.
An undefined key will have the same effect. The supported func-
tions are: backward-delete-char, vi-backward-delete-char,
clear-screen, redisplay, quoted-insert, vi-quoted-insert,
accept-and-hold, accept-and-infer-next-history, accept-line and
accept-line-and-down-history.
magic-space just inserts a space. vi-cmd-mode toggles between
the ‘main’ and ‘vicmd’ keymaps; the ‘main’ keymap (insert mode)
will be selected initially. history-incremental-search-back-
ward will get the next occurrence of the contents of the
mini-buffer. history-incremental-search-forward inverts the
sense of the search. vi-repeat-search and vi-rev-repeat-search
are similarly supported. The direction of the search is indi-
cated in the mini-buffer.
Any multi-character string that is not bound to one of the
above functions will beep and interrupt the search, leaving the
last found line in the buffer. Any single character that is not
bound to one of the above functions, or self-insert or
self-insert-unmeta, will have the same effect but the function
will be executed.
When called from a widget function by the zle command, the
incremental search commands can take a string argument. This
will be treated as a string of keys, as for arguments to the
bindkey command, and used as initial input for the command.
Any characters in the string which are unused by the incremen-
tal search will be silently ignored. For example,
zle history-incremental-search-backward forceps
will search backwards for forceps, leaving the minibuffer con-
taining the string ‘forceps’.
history-incremental-search-forward (^S ^Xs) (unbound) (unbound)
Search forward incrementally for a specified string. The
search is case-insensitive if the search string does not have
uppercase letters and no numeric argument was given. The
string may begin with ‘^’ to anchor the search to the beginning
of the line. The functions available in the mini-buffer are
the same as for history-incremental-search-backward.
history-search-backward (ESC-P ESC-p) (unbound) (unbound)
Search backward in the history for a line beginning with the
first word in the buffer.
If called from a function by the zle command with arguments,
the first argument is taken as the string for which to search,
rather than the first word in the buffer.
vi-history-search-backward (unbound) (/) (unbound)
Search backward in the history for a specified string. The
string may begin with ‘^’ to anchor the search to the beginning
of the line.
A restricted set of editing functions is available in the
mini-buffer. An interrupt signal, as defined by the stty set-
ting, will stop the search. The functions available in the
mini-buffer are: accept-line, backward-delete-char, vi-back-
ward-delete-char, backward-kill-word, vi-backward-kill-word,
clear-screen, redisplay, quoted-insert and vi-quoted-insert.
vi-cmd-mode is treated the same as accept-line, and magic-space
is treated as a space. Any other character that is not bound
to self-insert or self-insert-unmeta will beep and be ignored.
If the function is called from vi command mode, the bindings of
the current insert mode will be used.
If called from a function by the zle command with arguments,
the first argument is taken as the string for which to search,
rather than the first word in the buffer.
history-search-forward (ESC-N ESC-n) (unbound) (unbound)
Search forward in the history for a line beginning with the
first word in the buffer.
If called from a function by the zle command with arguments,
the first argument is taken as the string for which to search,
rather than the first word in the buffer.
vi-history-search-forward (unbound) (?) (unbound)
Search forward in the history for a specified string. The
string may begin with ‘^’ to anchor the search to the beginning
of the line. The functions available in the mini-buffer are the
same as for vi-history-search-backward. Argument handling is
also the same as for that command.
infer-next-history (^X^N) (unbound) (unbound)
Search in the history list for a line matching the current one
and fetch the event following it.
insert-last-word (ESC-_ ESC-.) (unbound) (unbound)
Insert the last word from the previous history event at the
cursor position. If a positive numeric argument is given,
insert that word from the end of the previous history event.
If the argument is zero or negative insert that word from the
left (zero inserts the previous command word). Repeating this
command replaces the word just inserted with the last word from
the history event prior to the one just used; numeric arguments
can be used in the same way to pick a word from that event.
When called from a shell function invoked from a user-defined
widget, the command can take one to three arguments. The first
argument specifies a history offset which applies to successive
calls to this widget: if is -1, the default behaviour is used,
while if it is 1, successive calls will move forwards through
the history. The value 0 can be used to indicate that the his-
tory line examined by the previous execution of the command
will be reexamined. Note that negative numbers should be pre-
ceded with a ‘--’ argument to avoid confusing them with
options.
If two arguments are given, the second specifies the word on
the command line in normal array index notation (as a more nat-
ural alternative to the prefix argument). Hence 1 is the first
word, and -1 (the default) is the last word.
If a third argument is given, its value is ignored, but it is
used to signify that the history offset is relative to the cur-
rent history line, rather than the one remembered after the
previous invocations of insert-last-word.
For example, the default behaviour of the command corresponds
to
zle insert-last-word -- -1 -1
while the command
zle insert-last-word -- -1 1 -
always copies the first word of the line in the history immedi-
ately before the line being edited. This has the side effect
that later invocations of the widget will be relative to that
line.
vi-repeat-search (unbound) (n) (unbound)
Repeat the last vi history search.
vi-rev-repeat-search (unbound) (N) (unbound)
Repeat the last vi history search, but in reverse.
up-line-or-history (^P ESC-[A) (k) (ESC-[A)
Move up a line in the buffer, or if already at the top line,
move to the previous event in the history list.
vi-up-line-or-history (unbound) (-) (unbound)
Move up a line in the buffer, or if already at the top line,
move to the previous event in the history list. Then move to
the first non-blank character on the line.
up-line-or-search
Move up a line in the buffer, or if already at the top line,
search backward in the history for a line beginning with the
first word in the buffer.
If called from a function by the zle command with arguments,
the first argument is taken as the string for which to search,
rather than the first word in the buffer.
up-history (unbound) (^P) (unbound)
Move to the previous event in the history list.
history-beginning-search-forward
Search forward in the history for a line beginning with the
current line up to the cursor. This leaves the cursor in its
original position.
Modifying Text
vi-add-eol (unbound) (A) (unbound)
Move to the end of the line and enter insert mode.
vi-add-next (unbound) (a) (unbound)
Enter insert mode after the current cursor position, without
changing lines.
backward-delete-char (^H ^?) (unbound) (unbound)
Delete the character behind the cursor.
vi-backward-delete-char (unbound) (X) (^H)
Delete the character behind the cursor, without changing lines.
If in insert mode, this won’t delete past the point where
insert mode was last entered.
backward-delete-word
Delete the word behind the cursor.
backward-kill-line
Kill from the beginning of the line to the cursor position.
backward-kill-word (^W ESC-^H ESC-^?) (unbound) (unbound)
Kill the word behind the cursor.
vi-backward-kill-word (unbound) (unbound) (^W)
Kill the word behind the cursor, without going past the point
where insert mode was last entered.
capitalize-word (ESC-C ESC-c) (unbound) (unbound)
Capitalize the current word and move past it.
vi-change (unbound) (c) (unbound)
Read a movement command from the keyboard, and kill from the
cursor position to the endpoint of the movement. Then enter
insert mode. If the command is vi-change, change the current
line.
vi-change-eol (unbound) (C) (unbound)
Kill to the end of the line and enter insert mode.
vi-change-whole-line (unbound) (S) (unbound)
Kill the current line and enter insert mode.
copy-region-as-kill (ESC-W ESC-w) (unbound) (unbound)
Copy the area from the cursor to the mark to the kill buffer.
copy-prev-word (ESC-^_) (unbound) (unbound)
Duplicate the word to the left of the cursor.
copy-prev-shell-word (ESC-^_) (unbound) (unbound)
Like copy-prev-word, but the word is found by using shell pars-
ing, whereas copy-prev-word looks for blanks. This makes a dif-
ference when the word is quoted and contains spaces.
vi-delete (unbound) (d) (unbound)
Read a movement command from the keyboard, and kill from the
cursor position to the endpoint of the movement. If the com-
mand is vi-delete, kill the current line.
delete-char
Delete the character under the cursor.
vi-delete-char (unbound) (x) (unbound)
Delete the character under the cursor, without going past the
end of the line.
delete-word
Delete the current word.
down-case-word (ESC-L ESC-l) (unbound) (unbound)
Convert the current word to all lowercase and move past it.
kill-word (ESC-D ESC-d) (unbound) (unbound)
Kill the current word.
gosmacs-transpose-chars
Exchange the two characters behind the cursor.
vi-indent (unbound) (>) (unbound)
Indent a number of lines.
vi-insert (unbound) (i) (unbound)
Enter insert mode.
vi-insert-bol (unbound) (I) (unbound)
Move to the first non-blank character on the line and enter
insert mode.
vi-join (^X^J) (J) (unbound)
Join the current line with the next one.
kill-line (^K) (unbound) (unbound)
Kill from the cursor to the end of the line. If already on the
end of the line, kill the newline character.
vi-kill-line (unbound) (unbound) (^U)
Kill from the cursor back to wherever insert mode was last
entered.
vi-kill-eol (unbound) (D) (unbound)
Kill from the cursor to the end of the line.
kill-region
Kill from the cursor to the mark.
kill-buffer (^X^K) (unbound) (unbound)
Kill the entire buffer.
kill-whole-line (^U) (unbound) (unbound)
Kill the current line.
vi-match-bracket (^X^B) (%) (unbound)
Move to the bracket character (one of {}, () or []) that
matches the one under the cursor. If the cursor is not on a
bracket character, move forward without going past the end of
the line to find one, and then go to the matching bracket.
vi-open-line-above (unbound) (O) (unbound)
Open a line above the cursor and enter insert mode.
vi-open-line-below (unbound) (o) (unbound)
Open a line below the cursor and enter insert mode.
vi-oper-swap-case
Read a movement command from the keyboard, and swap the case of
all characters from the cursor position to the endpoint of the
movement. If the movement command is vi-oper-swap-case, swap
the case of all characters on the current line.
overwrite-mode (^X^O) (unbound) (unbound)
Toggle between overwrite mode and insert mode.
vi-put-before (unbound) (P) (unbound)
Insert the contents of the kill buffer before the cursor. If
the kill buffer contains a sequence of lines (as opposed to
characters), paste it above the current line.
vi-put-after (unbound) (p) (unbound)
Insert the contents of the kill buffer after the cursor. If
the kill buffer contains a sequence of lines (as opposed to
characters), paste it below the current line.
quoted-insert (^V) (unbound) (unbound)
Insert the next character typed into the buffer literally. An
interrupt character will not be inserted.
vi-quoted-insert (unbound) (unbound) (^Q ^V)
Display a ‘^’ at the cursor position, and insert the next char-
acter typed into the buffer literally. An interrupt character
will not be inserted.
quote-line (ESC-’) (unbound) (unbound)
Quote the current line; that is, put a ‘’’ character at the
beginning and the end, and convert all ‘’’ characters to
‘’\’’’.
quote-region (ESC-") (unbound) (unbound)
Quote the region from the cursor to the mark.
vi-replace (unbound) (R) (unbound)
Enter overwrite mode.
vi-repeat-change (unbound) (.) (unbound)
Repeat the last vi mode text modification. If a count was used
with the modification, it is remembered. If a count is given
to this command, it overrides the remembered count, and is
remembered for future uses of this command. The cut buffer
specification is similarly remembered.
vi-replace-chars (unbound) (r) (unbound)
Replace the character under the cursor with a character read
from the keyboard.
self-insert (printable characters) (unbound) (printable characters and
some control characters)
Insert a character into the buffer at the cursor position.
self-insert-unmeta (ESC-^I ESC-^J ESC-^M) (unbound) (unbound)
Insert a character into the buffer after stripping the meta bit
and converting ^M to ^J.
vi-substitute (unbound) (s) (unbound)
Substitute the next character(s).
vi-swap-case (unbound) (~) (unbound)
Swap the case of the character under the cursor and move past
it.
transpose-chars (^T) (unbound) (unbound)
Exchange the two characters to the left of the cursor if at end
of line, else exchange the character under the cursor with the
character to the left.
transpose-words (ESC-T ESC-t) (unbound) (unbound)
Exchange the current word with the one before it.
vi-unindent (unbound) (<) (unbound)
Unindent a number of lines.
up-case-word (ESC-U ESC-u) (unbound) (unbound)
Convert the current word to all caps and move past it.
yank (^Y) (unbound) (unbound)
Insert the contents of the kill buffer at the cursor position.
yank-pop (ESC-y) (unbound) (unbound)
Remove the text just yanked, rotate the kill-ring, and yank the
new top. Only works following yank or yank-pop.
vi-yank (unbound) (y) (unbound)
Read a movement command from the keyboard, and copy the region
from the cursor position to the endpoint of the movement into
the kill buffer. If the command is vi-yank, copy the current
line.
vi-yank-whole-line (unbound) (Y) (unbound)
Copy the current line into the kill buffer.
vi-yank-eol
Copy the region from the cursor position to the end of the line
into the kill buffer. Arguably, this is what Y should do in
vi, but it isn’t what it actually does.
Arguments
digit-argument (ESC-0..ESC-9) (1-9) (unbound)
Start a new numeric argument, or add to the current one. See
also vi-digit-or-beginning-of-line. This only works if bound
to a key sequence ending in a decimal digit.
Inside a widget function, a call to this function treats the
last key of the key sequence which called the widget as the
digit.
neg-argument (ESC--) (unbound) (unbound)
Changes the sign of the following argument.
universal-argument
Multiply the argument of the next command by 4. Alternatively,
if this command is followed by an integer (positive or nega-
tive), use that as the argument for the next command. Thus
digits cannot be repeated using this command. For example, if
this command occurs twice, followed immediately by for-
ward-char, move forward sixteen spaces; if instead it is fol-
lowed by -2, then forward-char, move backward two spaces.
Inside a widget function, if passed an argument, i.e. ‘zle uni-
versal-argument num’, the numerical argument will be set to
num; this is equivalent to ‘NUMERIC=num’.
Completion
accept-and-menu-complete
In a menu completion, insert the current completion into the
buffer, and advance to the next possible completion.
complete-word
Attempt completion on the current word.
delete-char-or-list (^D) (unbound) (unbound)
Delete the character under the cursor. If the cursor is at the
end of the line, list possible completions for the current
word.
expand-cmd-path
Expand the current command to its full pathname.
expand-or-complete (TAB) (unbound) (TAB)
Attempt shell expansion on the current word. If that fails,
attempt completion.
expand-or-complete-prefix
Attempt shell expansion on the current word up to cursor.
expand-history (ESC-space ESC-!) (unbound) (unbound)
Perform history expansion on the edit buffer.
expand-word (^X*) (unbound) (unbound)
Attempt shell expansion on the current word.
list-choices (ESC-^D) (^D =) (^D)
List possible completions for the current word.
list-expand (^Xg ^XG) (^G) (^G)
List the expansion of the current word.
magic-space
Perform history expansion and insert a space into the buffer.
This is intended to be bound to space.
menu-complete
Like complete-word, except that menu completion is used. See
the MENU_COMPLETE option.
menu-expand-or-complete
Like expand-or-complete, except that menu completion is used.
reverse-menu-complete
Perform menu completion, like menu-complete, except that if a
menu completion is already in progress, move to the previous
completion rather than the next.
end-of-list
When a previous completion displayed a list below the prompt,
this widget can be used to move the prompt below the list.
Miscellaneous
accept-and-hold (ESC-A ESC-a) (unbound) (unbound)
Push the contents of the buffer on the buffer stack and execute
it.
accept-and-infer-next-history
Execute the contents of the buffer. Then search the history
list for a line matching the current one and push the event
following onto the buffer stack.
accept-line (^J ^M) (^J ^M) (^J ^M)
Finish editing the buffer. Normally this causes the buffer to
be executed as a shell command.
accept-line-and-down-history (^O) (unbound) (unbound)
Execute the current line, and push the next history event on
the the buffer stack.
beep Beep, unless the BEEP option is unset.
vi-cmd-mode (^X^V) (unbound) (^[)
Enter command mode; that is, select the ‘vicmd’ keymap. Yes,
this is bound by default in emacs mode.
vi-caps-lock-panic
Hang until any lowercase key is pressed. This is for vi users
without the mental capacity to keep track of their caps lock
key (like the author).
clear-screen (^L ESC-^L) (^L) (^L)
Clear the screen and redraw the prompt.
describe-key-briefly
Reads a key sequence, then prints the function bound to that
sequence.
exchange-point-and-mark (^X^X) (unbound) (unbound)
Exchange the cursor position with the position of the mark.
execute-named-cmd (ESC-x) (unbound) (unbound)
Read the name of an editor command and execute it. A
restricted set of editing functions is available in the
mini-buffer. An interrupt signal, as defined by the stty set-
ting, will abort the function. The allowed functions are: back-
ward-delete-char, vi-backward-delete-char, clear-screen, redis-
play, quoted-insert, vi-quoted-insert, backward-kill-word,
vi-backward-kill-word, kill-whole-line, vi-kill-line, back-
ward-kill-line, list-choices, delete-char-or-list, com-
plete-word, accept-line, expand-or-complete and expand-or-com-
plete-prefix.
kill-region kills the last word, and vi-cmd-mode is treated the
same as accept-line. The space and tab characters, if not
bound to one of these functions, will complete the name and
then list the possibilities if the AUTO_LIST option is set.
Any other character that is not bound to self-insert or
self-insert-unmeta will beep and be ignored. The bindings of
the current insert mode will be used.
execute-last-named-cmd (ESC-z) (unbound) (unbound)
Redo the last function executed with execute-named-cmd.
get-line (ESC-G ESC-g) (unbound) (unbound)
Pop the top line off the buffer stack and insert it at the cur-
sor position.
pound-insert (unbound) (#) (unbound)
If there is no # character at the beginning of the buffer, add
one to the beginning of each line. If there is one, remove a #
from each line that has one. In either case, accept the cur-
rent line. The INTERACTIVE_COMMENTS option must be set for
this to have any usefulness.
vi-pound-insert
If there is no # character at the beginning of the current
line, add one. If there is one, remove it. The INTERAC-
TIVE_COMMENTS option must be set for this to have any useful-
ness.
push-input
Push the entire current multiline construct onto the buffer
stack and return to the top-level (PS1) prompt. If the current
parser construct is only a single line, this is exactly like
push-line. Next time the editor starts up or is popped with
get-line, the construct will be popped off the top of the
buffer stack and loaded into the editing buffer.
push-line (^Q ESC-Q ESC-q) (unbound) (unbound)
Push the current buffer onto the buffer stack and clear the
buffer. Next time the editor starts up, the buffer will be
popped off the top of the buffer stack and loaded into the
editing buffer.
push-line-or-edit
At the top-level (PS1) prompt, equivalent to push-line. At a
secondary (PS2) prompt, move the entire current multiline con-
struct into the editor buffer. The latter is equivalent to
push-input followed by get-line.
recursive-edit
Only useful from a user-defined widget. At this point in the
function, the editor regains control until one of the standard
widgets which would normally cause zle to exit (typically an
accept-line caused by hitting the return key) is executed.
Instead, control returns to the user-defined widget. The sta-
tus returned is non-zero if the return was caused by an error,
but the function still continues executing and hence may tidy
up. This makes it safe for the user-defined widget to alter
the command line or key bindings temporarily.
The following widget, caps-lock, serves as an example.
self-insert-ucase() {
LBUFFER+=${(U)KEYS[-1]}
}
integer stat
zle -N self-insert self-insert-ucase
zle -A caps-lock save-caps-lock
zle -A accept-line caps-lock
zle recursive-edit
stat=$?
zle -A .self-insert self-insert
zle -A save-caps-lock caps-lock
zle -D save-caps-lock
(( stat )) && zle send-break
return $stat
This causes typed letters to be inserted capitalised until
either accept-line (i.e. typically the return key) is typed or
the caps-lock widget is invoked again; the later is handled by
saving the old definition of caps-lock as save-caps-lock and
then rebinding it to invoke accept-line. Note that an error
from the recursive edit is detected as a non-zero return status
and propagated by using the send-break widget.
redisplay (unbound) (^R) (^R)
Redisplays the edit buffer.
send-break (^G ESC-^G) (unbound) (unbound)
Abort the current editor function, e.g. execute-named-command,
or the editor itself, e.g. if you are in vared. Otherwise abort
the parsing of the current line.
run-help (ESC-H ESC-h) (unbound) (unbound)
Push the buffer onto the buffer stack, and execute the command
‘run-help cmd’, where cmd is the current command. run-help is
normally aliased to man.
vi-set-buffer (unbound) (") (unbound)
Specify a buffer to be used in the following command. There
are 35 buffers that can be specified: the 26 ‘named’ buffers "a
to "z and the nine ‘queued’ buffers "1 to "9. The named
buffers can also be specified as "A to "Z.
When a buffer is specified for a cut command, the text being
cut replaces the previous contents of the specified buffer. If
a named buffer is specified using a capital, the newly cut text
is appended to the buffer instead of overwriting it.
If no buffer is specified for a cut command, "1 is used, and
the contents of "1 to "8 are each shifted along one buffer; the
contents of "9 is lost.
vi-set-mark (unbound) (m) (unbound)
Set the specified mark at the cursor position.
set-mark-command (^@) (unbound) (unbound)
Set the mark at the cursor position.
spell-word (ESC-$ ESC-S ESC-s) (unbound) (unbound)
Attempt spelling correction on the current word.
undefined-key
This command is executed when a key sequence that is not bound
to any command is typed. By default it beeps.
undo (^_ ^Xu ^X^U) (unbound) (unbound)
Incrementally undo the last text modification.
redo Incrementally redo undone text modifications.
vi-undo-change (unbound) (u) (unbound)
Undo the last text modification. If repeated, redo the modifi-
cation.
what-cursor-position (^X=) (unbound) (unbound)
Print the character under the cursor, its code as an octal,
decimal and hexadecimal number, the current cursor position
within the buffer and the column of the cursor in the current
line.
where-is
Read the name of an editor command and and print the listing of
key sequences that invoke the specified command.
which-command (ESC-?) (unbound) (unbound)
Push the buffer onto the buffer stack, and execute the command
‘which-command cmd’. where cmd is the current command.
which-command is normally aliased to whence.
vi-digit-or-beginning-of-line (unbound) (0) (unbound)
If the last command executed was a digit as part of an argu-
ment, continue the argument. Otherwise, execute vi-begin-
ZSHCOMPWID(1) ZSHCOMPWID(1)
ning-of-line.
NAME
zshcompwid - zsh completion widgets
DESCRIPTION
The shell’s programmable completion mechanism can be manipulated in
two ways; here the low-level features supporting the newer, func-
tion-based mechanism are defined. A complete set of shell functions
based on these features is described in zshcompsys(1), and users with
no interest in adding to that system (or, potentially, writing their
own --- see dictionary entry for ‘hubris’) should skip this section.
The older system based on the compctl builtin command is described in
zshcompctl(1).
Completion widgets are defined by the -C option to the zle builtin
command provided by the zsh/zle module (see zshzle(1)). For example,
zle -C complete expand-or-complete completer
defines a widget named ‘complete’. The second argument is the name of
any of the builtin widgets that handle completions: complete-word,
expand-or-complete, expand-or-complete-prefix, menu-complete,
menu-expand-or-complete, reverse-menu-complete, list-choices, or
delete-char-or-list. Note that this will still work even if the wid-
get in question has been re-bound.
When this newly defined widget is bound to a key using the bindkey
builtin command defined in the zsh/zle module (see zshzle(1)), typing
that key will call the shell function ‘completer’. This function is
responsible for generating the possible matches using the builtins
described below. As with other ZLE widgets, the function is called
with its standard input closed.
Once the function returns, the completion code takes over control
again and treats the matches in the same manner as the specified
builtin widget, in this case expand-or-complete.
SPECIAL PARAMETERS
Inside completion widgets, and any functions called from them, some
parameters have special meaning; outside these functions they are not
special to the shell in any way. These parameters are used to pass
information between the completion code and the completion widget.
Some of the builtin commands and the condition codes use or change the
current values of these parameters. Any existing values will be hid-
den during execution of completion widgets; except for compstate, the
parameters are reset on each function exit (including nested function
calls from within the completion widget) to the values they had when
the function was entered.
CURRENT
This is the number of the current word, i.e. the word the cur-
sor is currently on in the words array. Note that this value
is only correct if the ksharrays option is not set.
IPREFIX
Initially this will be set to the empty string. This parameter
functions like PREFIX; it contains a string which precedes the
one in PREFIX and is not considered part of the list of
matches. Typically, a string is transferred from the beginning
of PREFIX to the end of IPREFIX, for example:
IPREFIX=${PREFIX%%\=*}=
PREFIX=${PREFIX#*=}
causes the part of the prefix up to and including the first
equal sign not to be treated as part of a matched string. This
can be done automatically by the compset builtin, see below.
ISUFFIX
As IPREFIX, but for a suffix that should not be considered part
of the matches; note that the ISUFFIX string follows the SUFFIX
string.
PREFIX Initially this will be set to the part of the current word from
the beginning of the word up to the position of the cursor; it
may be altered to give a common prefix for all matches.
QIPREFIX
This parameter is read-only and contains the quoted string up
to the word being completed. E.g. when completing ‘"foo’, this
parameter contains the double quote. If the -q option of
compset is used (see below), and the original string was ‘"foo
bar’ with the cursor on the ‘bar’, this parameter contains
‘"foo ’.
QISUFFIX
Like QIPREFIX, but containing the suffix.
SUFFIX Initially this will be set to the part of the current word from
the cursor position to the end; it may be altered to give a
common suffix for all matches. It is most useful when the
option COMPLETE_IN_WORD is set, as otherwise the whole word on
the command line is treated as a prefix.
compstate
This is an associative array with various keys and values that
the completion code uses to exchange information with the com-
pletion widget. The keys are:
all_quotes
The -q option of the compset builtin command (see below)
allows a quoted string to be broken into separate words;
if the cursor is on one of those words, that word will
be completed, possibly invoking ‘compset -q’ recur-
sively. With this key it is possible to test the types
of quoted strings which are currently broken into parts
in this fashion. Its value contains one character for
each quoting level. The characters are a single quote
or a double quote for strings quoted with these charac-
ters and a backslash for strings not starting with a
quote character. The first character in the value
always corresponds to the innermost quoting level.
context
This will be set by the completion code to the overall
context in which completion is attempted. Possible val-
ues are:
array_value
when completing inside the value of an array
parameter assignment; in this case the words
array contains the words inside the parentheses.
brace_parameter
when completing the name of a parameter in a
parameter expansion beginning with ${.
assign_parameter
when completing the name of a parameter in a
parameter assignment.
command
when completing for a normal command (either in
command position or for an argument of the com-
mand).
condition
when completing inside a ‘[[...]]’ conditional
expression; in this case the words array con-
tains only the words inside the conditional
expression.
math when completing in a mathematical environment
such as a ‘((...))’ construct.
parameter
when completing the name of a parameter in a
parameter expansion beginning with $ but not ${.
redirect
when completing after a redirection operator.
subscript
when completing inside a parameter subscript.
value when completing the value of a parameter assign-
ment.
exact Controls the behaviour when the REC_EXACT option is set.
It will be set to accept if an exact match would be
accepted, and will be unset otherwise.
If it was set when at least one match equal to the
string on the line was generated, the match is accepted.
exact_string
The string of an exact match if one was found, otherwise
unset.
ignored
The number of words that were ignored because they
matched one of the patterns given with the -F option to
the compadd builtin command.
insert This controls the manner in which a match is inserted
into the command line. On entry to the widget function,
if it is unset the command line is not to be changed; if
set to unambiguous, any prefix common to all matches is
to be inserted; if set to automenu-unambiguous, the com-
mon prefix is to be inserted and the next invocation of
the completion code may start menu completion (due to
the AUTO_MENU option being set); if set to menu or
automenu menu completion will be started for the matches
currently generated (in the latter case this will happen
because the AUTO_MENU is set). The value may also con-
tain the string ‘tab’ when the completion code would
normally not really do completion, but only insert the
TAB character.
On exit it may be set to any of the values above (where
setting it to the empty string is the same as unsetting
it), or to a number, in which case the match whose num-
ber is given will be inserted into the command line.
Negative numbers count backward from the last match
(with ‘-1’ selecting the last match) and out-of-range
values are wrapped around, so that a value of zero
selects the last match and a value one more than the
maximum selects the first. Unless the value of this key
ends in a space, the match is inserted as in a menu com-
pletion, i.e. without automatically appending a space.
Both menu and automenu may also specify the the number
of the match to insert, given after a colon. For exam-
ple, ‘menu:2’ says to start menu completion, beginning
with the second match.
Note that a value containing the substring ‘tab’ makes
the matches generated be ignored and only the TAB be
inserted.
Finally, it may also be set to all, which makes all
matches generated be inserted into the line.
insert_positions
When the completion system inserts an unambiguous string
into the line, there may be multiple places where char-
acters are missing or where the character inserted dif-
fers from at least one match. The value of this key
contains a colon separated list of all these positions,
as indexes into the command line.
last_prompt
If this is set to a non-empty string for every match
added, the completion code will move the cursor back to
the previous prompt after the list of completions has
been displayed. Initially this is set or unset accord-
ing to the ALWAYS_LAST_PROMPT option.
list This controls whether or how the list of matches will be
displayed. If it is unset or empty they will never be
listed; if its value begins with list, they will always
be listed; if it begins with autolist or ambiguous, they
will be listed when the AUTO_LIST or LIST_AMBIGUOUS
options respectively would normally cause them to be.
If the substring force appears in the value, this makes
the list be shown even if there is only one match. Nor-
mally, the list would be shown only if there are at
least two matches.
The value contains the substring packed if the
LIST_PACKED option is set. If this substring is given
for all matches added to a group, this group will show
the LIST_PACKED behavior. The same is done for the
LIST_ROWS_FIRST option with the substring rows.
Finally, if the value contains the string explanations,
only the explanation strings, if any, will be listed and
if it contains messages, only the messages (added with
the -x option of compadd) will be listed. If it con-
tains both explanations and messages both kinds of
explanation strings will be listed. It will be set
appropriately on entry to a completion widget and may be
changed there.
list_lines
This gives the number of lines that are needed to dis-
play the full list of completions. Note that to
calculate the total number of lines to display you need
to add the number of lines needed for the command line
to this value, this is available as the value of the
BUFFERLINES special parameter.
list_max
Initially this is set to the value of the LISTMAX param-
eter. It may be set to any other value; when the widget
exits this value will be used in the same way as the
value of LISTMAX.
nmatches
The number of matches generated and accepted by the com-
pletion code so far.
old_insert
On entry to the widget this will be set to the number of
the match of an old list of completions that is cur-
rently inserted into the command line. If no match has
been inserted, this is unset.
As with old_list, the value of this key will only be
used if it is the string keep. If it was set to this
value by the widget and there was an old match inserted
into the command line, this match will be kept and if
the value of the insert key specifies that another match
should be inserted, this will be inserted after the old
one.
old_list
This is set to yes if there is still a valid list of
completions from a previous completion at the time the
widget is invoked. This will usually be the case if and
only if the previous editing operation was a completion
widget or one of the builtin completion functions. If
there is a valid list and it is also currently shown on
the screen, the value of this key is shown.
After the widget has exited the value of this key is
only used if it was set to keep. In this case the com-
pletion code will continue to use this old list. If the
widget generated new matches, they will not be used.
parameter
The name of the parameter when completing in a subscript
or in the value of a parameter assignment.
pattern_insert
Normally this is set to menu, which specifies that menu
completion will be used whenever a set of matches was
generated using pattern matching. If it is set to any
other non-empty string by the user and menu completion
is not selected by other option settings, the code will
instead insert any common prefix for the generated
matches as with normal completion.
pattern_match
Locally controls the behaviour given by the GLOB_COM-
PLETE option. Initially it is set to ‘*’ if and only if
the option is set. The completion widget may set it to
this value, to an empty string (which has the same
effect as unsetting it), or to any other non-empty
string. If it is non-empty, unquoted metacharacters on
the command line will be treated as patterns; if it is
‘*’, then additionally a wildcard ‘*’ is assumed at the
cursor position; if it is empty or unset, metacharacters
will be treated literally.
Note that the matcher specifications given to the com-
padd builtin command are not used if this is set to a
non-empty string.
quote When completing inside quotes, this contains the quota-
tion character (i.e. either a single quote, a double
quote, or a backtick). Otherwise it is unset.
quoting
When completing inside single quotes, this is set to the
string single; inside double quotes, the string double;
inside backticks, the string backtick. Otherwise it is
unset.
redirect
The redirection operator when completing in a redirec-
tion position, i.e. one of <, >, etc.
restore
This is set to auto before a function is entered, which
forces the special parameters mentioned above (words,
CURRENT, PREFIX, IPREFIX, SUFFIX, and ISUFFIX) to be
restored to their previous values when the function
exits. If a function unsets it or sets it to any other
string, they will not be restored.
to_end Specifies the occasions on which the cursor is moved to
the end of a string when a match is inserted. On entry
to a widget function, it may be single if this will hap-
pen when a single unambiguous match was inserted or
match if it will happen any time a match is inserted
(for example, by menu completion; this is likely to be
the effect of the ALWAYS_TO_END option).
On exit, it may be set to single as above. It may also
be set to always, or to the empty string or unset; in
those cases the cursor will be moved to the end of the
string always or never respectively. Any other string
is treated as match.
unambiguous
This key is read-only and will always be set to the com-
mon (unambiguous) prefix the completion code has gener-
ated for all matches added so far.
unambiguous_cursor
This gives the position the cursor would be placed at if
the common prefix in the unambiguous key were inserted,
relative to the value of that key. The cursor would be
placed before the character whose index is given by this
key.
unambiguous_positions
This contains all positions where characters in the
unambiguous string are missing or where the character
inserted differs from at least one of the matches. The
positions are given as indexes into the string given by
the value of the unambiguous key.
vared If completion is called while editing a line using the
vared builtin, the value of this key is set to the name
of the parameter given as an argument to vared. This
key is only set while a vared command is active.
words This array contains the words present on the command line cur-
rently being edited.
BUILTIN COMMANDS
compadd [ -akqQfenUl12C ] [ -F array ]
[ -P prefix ] [ -S suffix ]
[ -p hidden-prefix ] [ -s hidden-suffix ]
[ -i ignored-prefix ] [ -I ignored-suffix ]
[ -W file-prefix ] [ -d array ]
[ -J name ] [ -V name ] [ -X explanation ] [ -x message ]
[ -r remove-chars ] [ -R remove-func ]
[ -D array ] [ -O array ] [ -A array ]
[ -E number ]
[ -M match-spec ] [ -- ] [ words ... ]
This builtin command can be used to add matches directly and
control all the information the completion code stores with
each possible match. The return value is zero if at least one
match was added and non-zero if no matches were added.
The completion code breaks the string to complete into seven
fields in the order:
<ipre><apre><hpre><word><hsuf><asuf><isuf>
The first field is an ignored prefix taken from the command
line, the contents of the IPREFIX parameter plus the string
given with the -i option. With the -U option, only the string
from the -i option is used. The field <apre> is an optional
prefix string given with the -P option. The <hpre> field is a
string that is considered part of the match but that should not
be shown when listing completions, given with the -p option;
for example, functions that do filename generation might spec-
ify a common path prefix this way. <word> is the part of the
match that should appear in the list of completions, i.e. one
of the words given at the end of the compadd command line. The
suffixes <hsuf>, <asuf> and <isuf> correspond to the prefixes
<hpre>, <apre> and <ipre> and are given by the options -s, -S
and -I, respectively.
The supported flags are:
-P prefix
This gives a string to be inserted before the given
words. The string given is not considered as part of
the match and any shell metacharacters in it will not be
quoted when the string is inserted.
-S suffix
Like -P, but gives a string to be inserted after the
match.
-p hidden-prefix
This gives a string that should be inserted into the
command line before the match but that should not appear
in the list of matches. Unless the -U option is given,
this string must be matched as part of the string on the
command line.
-s hidden-suffix
Like ‘-p’, but gives a string to insert after the match.
-i ignored-prefix
This gives a string to insert into the command line just
before any string given with the ‘-P’ option. Without
‘-P’ the string is inserted before the string given with
‘-p’ or directly before the match.
-I ignored-suffix
Like -i, but gives an ignored suffix.
-a With this flag the words are taken as names of arrays
and the possible matches are their values. If only some
elements of the arrays are needed, the words may also
contain subscripts, as in ‘foo[2,-1]’.
-k With this flag the words are taken as names of associa-
tive arrays and the possible matches are their keys. As
for -a, the words may also contain subscripts, as in
‘foo[(R)*bar*]’.
-d array
This adds per-match display strings. The array should
contain one element per word given. The completion code
will then display the first element instead of the first
word, and so on. The array may be given as the name of
an array parameter or directly as a space-separated list
of words in parentheses.
If there are fewer display strings than words, the left-
over words will be displayed unchanged and if there are
more display strings than words, the leftover display
strings will be silently ignored.
-l This option only has an effect if used together with the
-d option. If it is given, the display strings are
listed one per line, not arrayed in columns.
-J name
Gives the name of the group of matches the words should
be stored in.
-V name
Like -J but naming a unsorted group. These are in a dif-
ferent name space than groups created with the -J flag.
-1 If given together with the -V option, makes only consec-
utive duplicates in the group be removed. If combined
with the -J option, this has no visible effect. Note
that groups with and without this flag are in different
name spaces.
-2 If given together with the -J or -V option, makes all
duplicates be kept. Again, groups with and without this
flag are in different name spaces.
-X explanation
The explanation string will be printed with the list of
matches, above the group currently selected.
-x message
Like -X, but the message will be printed even if there
are no matches in the group.
-q The suffix given with -S will be automatically removed
if the next character typed is a blank or does not
insert anything, or if the suffix consists of only one
character and the next character typed is the same char-
acter.
-r remove-chars
This is a more versatile form of the -q option. The
suffix given with -S or the slash automatically added
after completing directories will be automatically
removed if the next character typed inserts one of the
characters given in the remove-chars. This string is
parsed as a characters class and understands the back-
slash sequences used by the print command. For example,
‘-r "a-z\t"’ removes the suffix if the next character
typed inserts a lowercase character or a TAB, and ‘-r
"^0-9"’ removes the suffix if the next character typed
inserts anything but a digit. One extra backslash
sequence is understood in this string: ‘\-’ stands for
all characters that insert nothing. Thus ‘-S "=" -q’ is
the same as ‘-S "=" -r "= \t\n\-"’.
This option may also be used without the -S option; then
any automatically added space will be removed when one
of the characters in the list is typed.
-R remove-func
This is another form of the -r option. When a suffix has
been inserted and the completion accepted, the function
remove-func will be called after the next character
typed. It is passed the length of the suffix as an
argument and can use the special parameters available in
ordinary (non-completion) zle widgets (see zshzle(1)) to
analyse and modify the command line.
-f If this flag is given, all of the matches built from
words are marked as being the names of files. They are
not required to be actual filenames, but if they are,
and the option LIST_TYPES is set, the characters
describing the types of the files in the completion
lists will be shown. This also forces a slash to be
added when the name of a directory is completed.
-e This flag can be used to tell the completion code that
the matches added are parameter names for a parameter
expansion. This will make the AUTO_PARAM_SLASH and
AUTO_PARAM_KEYS options be used for the matches.
-W file-prefix
This string is a pathname that will be prepended to each
of the matches formed by the given words together with
any prefix specified by the -p option to form a complete
filename for testing. Hence it is only useful if com-
bined with the -f flag, as the tests will not otherwise
be performed.
-F array
Specifies an array containing patterns. Words matching
one of these patterns are ignored, i.e. not considered
to be possible matches.
The array may be the name of an array parameter or a
list of literal patterns enclosed in parentheses and
quoted, as in ‘-F "(*?.o *?.h)"’. If the name of an
array is given, the elements of the array are taken as
the patterns.
-Q This flag instructs the completion code not to quote any
metacharacters in the words when inserting them into the
command line.
-M match-spec
This gives local match specifications as described below
in the section ‘Matching Control’. This option may be
given more than once. In this case all match-specs given
are concatenated with spaces between them to form the
specification string to use. Note that they will only
be used if the -U option is not given.
-n Specifies that the words added are to be used as possi-
ble matches, but are not to appear in the completion
listing.
-U If this flag is given, all words given will be accepted
and no matching will be done by the completion code.
Normally this is used in functions that do the matching
themselves.
-O array
If this option is given, the words are not added to the
set of possible completions. Instead, matching is done
as usual and all of the words given as arguments that
match the string on the command line will be stored in
the array parameter whose name is given as array.
-A array
As the -O option, except that instead of those of the
words which match being stored in array, the strings
generated internally by the completion code are stored.
For example, with a matching specification of ‘-M
"L:|no="’, the string ‘nof’ on the command line and the
string ‘foo’ as one of the words, this option stores the
string ‘nofoo’ in the array, whereas the -O option
stores the ‘foo’ originally given.
-D array
As with -O, the words are not added to the set of possi-
ble completions. Instead, the completion code tests
whether each word in turn matches what is on the line.
If the n’th word does not match, the n’th element of the
array is removed. Elements for which the corresponding
word is matched are retained.
-C This option adds a special match which expands to all
other matches when inserted into the line, even those
that are added after this option is used. Together with
the -d option it is possible to specify a string that
should be displayed in the list for this special match.
If no string is given, it will be shown as a string con-
taining the strings that would be inserted for the other
matches, truncated to the width of the screen.
-E This option adds number empty matches after the words
have been added. An empty match takes up space in com-
pletion listings but will never be inserted in the line
and can’t be selected with menu completion or menu
selection. This makes empty matches only useful to for-
mat completion lists and to make explanatory string be
shown in completion lists (since empty matches can be
given display strings with the -d option). And because
all but one empty string would otherwise be removed,
this option implies the -V and -2 options (even if an
explicit -J option is given).
-
-- This flag ends the list of flags and options. All argu-
ments after it will be taken as the words to use as
matches even if they begin with hyphens.
Except for the -M flag, if any of these flags is given more
than once, the first one (and its argument) will be used.
compset -p number
compset -P [ number ] pattern
compset -s number
compset -S [ number ] pattern
compset -n begin [ end ]
compset -N beg-pat [ end-pat ]
compset -q
This command simplifies modification of the special parameters,
while its return value allows tests on them to be carried out.
The options are:
-p number
If the contents of the PREFIX parameter is longer than
number characters, the first number characters are
removed from it and appended to the contents of the
IPREFIX parameter.
-P [ number ] pattern
If the value of the PREFIX parameter begins with any-
thing that matches the pattern, the matched portion is
removed from PREFIX and appended to IPREFIX.
Without the optional number, the longest match is taken,
but if number is given, anything up to the number’th
match is moved. If the number is negative, the num-
ber’th longest match is moved. For example, if PREFIX
contains the string ‘a=b=c’, then compset -P ’*\=’ will
move the string ‘a=b=’ into the IPREFIX parameter, but
compset -P 1 ’*\=’ will move only the string ‘a=’.
-s number
As -p, but transfer the last number characters from the
value of SUFFIX to the front of the value of ISUFFIX.
-S [ number ] pattern
As -P, but match the last portion of SUFFIX and transfer
the matched portion to the front of the value of ISUF-
FIX.
-n begin [ end ]
If the current word position as specified by the parame-
ter CURRENT is greater than or equal to begin, anything
up to the begin’th word is removed from the words array
and the value of the parameter CURRENT is decremented by
begin.
If the optional end is given, the modification is done
only if the current word position is also less than or
equal to end. In this case, the words from position end
onwards are also removed from the words array.
Both begin and end may be negative to count backwards
from the last element of the words array.
-N beg-pat [ end-pat ]
If one of the elements of the words array before the one
at the index given by the value of the parameter CURRENT
matches the pattern beg-pat, all elements up to and
including the matching one are removed from the words
array and the value of CURRENT is changed to point to
the same word in the changed array.
If the optional pattern end-pat is also given, and there
is an element in the words array matching this pattern,
the parameters are modified only if the index of this
word is higher than the one given by the CURRENT parame-
ter (so that the matching word has to be after the cur-
sor). In this case, the words starting with the one
matching end-pat are also removed from the words array.
If words contains no word matching end-pat, the testing
and modification is performed as if it were not given.
-q The word currently being completed is split on spaces
into separate words, respecting the usual shell quoting
conventions. The resulting words are stored in the
words array, and CURRENT, PREFIX, SUFFIX, QIPREFIX, and
QISUFFIX are modified to reflect the word part that is
completed.
In all the above cases the return value is zero if the test
succeeded and the parameters were modified and non-zero other-
wise. This allows one to use this builtin in tests such as:
if compset -P ’*\=’; then ...
This forces anything up to and including the last equal sign to
be ignored by the completion code.
compcall [ -TD ]
This allows the use of completions defined with the compctl
builtin from within completion widgets. The list of matches
will be generated as if one of the non-widget completion func-
tion (complete-word, etc.) had been called, except that only
compctls given for specific commands are used. To force the
code to try completions defined with the -T option of compctl
and/or the default completion (whether defined by compctl -D or
the builtin default) in the appropriate places, the -T and/or
-D flags can be passed to compcall.
The return value can be used to test if a matching compctl def-
inition was found. It is non-zero if a compctl was found and
zero otherwise.
Note that this builtin is defined by the zsh/compctl module.
CONDITION CODES
The following additional condition codes for use within the [[ ... ]]
construct are available in completion widgets. These work on the spe-
cial parameters. All of these tests can also be performed by the
compset builtin, but in the case of the condition codes the contents
of the special parameters are not modified.
-prefix [ number ] pattern
true if the test for the -P option of compset would succeed.
-suffix [ number ] pattern
true if the test for the -S option of compset would succeed.
-after beg-pat
true if the test of the -N option with only the beg-pat given
would succeed.
-between beg-pat end-pat
true if the test for the -N option with both patterns would
succeed.
MATCHING CONTROL
It is possible by use of the -M option of the compadd builtin command
to specify how the characters in the string to be completed (referred
to here as the command line) map onto the characters in the list of
matches produced by the completion code (referred to here as the trial
completions). Note that this is not used if the command line contains
a glob pattern and the GLOB_COMPLETE option is set or the pat-
tern_match of the compstate special association is set to a non-empty
string.
The match-spec given as the argument to the -M option (see ‘Builtin
Commands’ above) consists of one or more matching descriptions sepa-
rated by whitespace. Each description consists of a letter followed
by a colon and then the patterns describing which character sequences
on the line match which character sequences in the trial completion.
Any sequence of characters not handled in this fashion must match
exactly, as usual.
The forms of match-spec understood are as follows. In each case, the
form with an uppercase initial character retains the string already
typed on the command line as the final result of completion, while
with a lowercase initial character the string on the command line is
changed into the corresponding part of the trial completion.
m:lpat=tpat
M:lpat=tpat
Here, lpat is a pattern that matches on the command line, cor-
responding to tpat which matches in the trial completion.
l:lanchor|lpat=tpat
L:lanchor|lpat=tpat
l:lanchor||ranchor=tpat
L:lanchor||ranchor=tpat
b:lpat=tpat
B:lpat=tpat
These letters are for patterns that are anchored by another
pattern on the left side. Matching for lpat and tpat is as for
m and M, but the pattern lpat matched on the command line must
be preceded by the pattern lanchor. The lanchor can be blank
to anchor the match to the start of the command line string;
otherwise the anchor can occur anywhere, but must match in both
the command line and trial completion strings.
If no lpat is given but a ranchor is, this matches the gap
between substrings matched by lanchor and ranchor. Unlike lan-
chor, the ranchor only needs to match the trial completion
string.
The b and B forms are similar to l and L with an empty anchor,
but need to match only the beginning of the trial completion or
the word on the command line, respectively.
r:lpat|ranchor=tpat
R:lpat|ranchor=tpat
r:lanchor||ranchor=tpat
R:lanchor||ranchor=tpat
e:lpat=tpat
E:lpat=tpat
As l, L, b and B, with the difference that the command line and
trial completion patterns are anchored on the right side. Here
an empty ranchor and the e and E forms force the match to the
end of the trial completion or command line string.
Each lpat, tpat or anchor is either an empty string or consists of a
sequence of literal characters (which may be quoted with a backslash),
question marks, character classes, and correspondence classes; ordi-
nary shell patterns are not used. Literal characters match only them-
selves, question marks match any character, and character classes are
formed as for globbing and match any character in the given set.
Correspondence classes are defined like character classes, but with
two differences: they are delimited by a pair of braces, and negated
classes are not allowed, so the characters ! and ^ have no special
meaning directly after the opening brace. They indicate that a range
of characters on the line match a range of characters in the trial
completion, but (unlike ordinary character classes) paired according
to the corresponding position in the sequence. For example, to make
any lowercase letter on the line match the corresponding uppercase
letter in the trial completion, you can use ‘m:{a-z}={A-Z}’. More
than one pair of classes can occur, in which case the first class
before the = corresponds to the first after it, and so on. If one
side has more such classes than the other side, the superfluous
classes behave like normal character classes. In anchor patterns cor-
respondence classes also behave like normal character classes.
The pattern tpat may also be one or two stars, ‘*’ or ‘**’. This means
that the pattern on the command line can match any number of charac-
ters in the trial completion. In this case the pattern must be
anchored (on either side); in the case of a single star, the anchor
then determines how much of the trial completion is to be included ---
only the characters up to the next appearance of the anchor will be
matched. With two stars, substrings matched by the anchor can be
matched, too.
Examples:
The keys of the options association defined by the parameter module
are the option names in all-lowercase form, without underscores, and
without the optional no at the beginning even though the builtins
setopt and unsetopt understand option names with uppercase letters,
underscores, and the optional no. The following alters the matching
rules so that the prefix no and any underscore are ignored when trying
to match the trial completions generated and uppercase letters on the
line match the corresponding lowercase letters in the words:
compadd -M ’L:|[nN][oO]= M:_= M:{A-Z}={a-z}’ - \
${(k)options}
The first part says that the pattern ‘[nN][oO]’ at the beginning (the
empty anchor before the pipe symbol) of the string on the line matches
the empty string in the list of words generated by completion, so it
will be ignored if present. The second part does the same for an
underscore anywhere in the command line string, and the third part
uses correspondence classes so that any uppercase letter on the line
matches the corresponding lowercase letter in the word. The use of the
uppercase forms of the specification characters (L and M) guarantees
that what has already been typed on the command line (in particular
the prefix no) will not be deleted.
Note that the use of L in the first part means that it matches only
when at the beginning of both the command line string and the trial
completion. I.e., the string ‘_NO_f’ would not be completed to
‘_NO_foo’, nor would ‘NONO_f’ be completed to ‘NONO_foo’ because of
the leading underscore or the second ‘NO’ on the line which makes the
pattern fail even though they are otherwise ignored. To fix this, one
would use ‘B:[nN][oO]=’ instead of the first part. As described above,
this matches at the beginning of the trial completion, independent of
other characters or substrings at the beginning of the command line
word which are ignored by the same or other match-specs.
The second example makes completion case insensitive. This is just
the same as in the option example, except here we wish to retain the
characters in the list of completions:
compadd -M ’m:{a-z}={A-Z}’ ...
This makes lowercase letters match their uppercase counterparts. To
make uppercase letters match the lowercase forms as well:
compadd -M ’m:{a-zA-Z}={A-Za-z}’ ...
A nice example for the use of * patterns is partial word completion.
Sometimes you would like to make strings like ‘c.s.u’ complete to
strings like ‘comp.source.unix’, i.e. the word on the command line
consists of multiple parts, separated by a dot in this example, where
each part should be completed separately --- note, however, that the
case where each part of the word, i.e. ‘comp’, ‘source’ and ‘unix’ in
this example, is to be completed from separate sets of matches is a
different problem to be solved by the implementation of the completion
widget. The example can be handled by:
compadd -M ’r:|.=* r:|=*’ \
- comp.sources.unix comp.sources.misc ...
The first specification says that lpat is the empty string, while
anchor is a dot; tpat is *, so this can match anything except for the
‘.’ from the anchor in the trial completion word. So in ‘c.s.u’, the
matcher sees ‘c’, followed by the empty string, followed by the anchor
‘.’, and likewise for the second dot, and replaces the empty strings
before the anchors, giving ‘c[omp].s[ources].u[nix]’, where the last
part of the completion is just as normal.
With the pattern shown above, the string ‘c.u’ could not be completed
to ‘comp.sources.unix’ because the single star means that no dot
(matched by the anchor) can be skipped. By using two stars as in
‘r:|.=**’, however, ‘c.u’ could be completed to ‘comp.sources.unix’.
This also shows that in some cases, especially if the anchor is a real
pattern, like a character class, the form with two stars may result in
more matches than one would like.
The second specification is needed to make this work when the cursor
is in the middle of the string on the command line and the option COM-
PLETE_IN_WORD is set. In this case the completion code would normally
try to match trial completions that end with the string as typed so
far, i.e. it will only insert new characters at the cursor position
rather then at the end. However in our example we would like the code
to recognise matches which contain extra characters after the string
on the line (the ‘nix’ in the example). Hence we say that the empty
string at the end of the string on the line matches any characters at
the end of the trial completion.
More generally, the specification
compadd -M ’r:|[.,_-]=* r:|=*’ ...
allows one to complete words with abbreviations before any of the
characters in the square brackets. For example, to complete veryvery-
longfile.c rather than veryverylongheader.h with the above in effect,
you can just type very.c before attempting completion.
The specifications with both a left and a right anchor are useful to
complete partial words whose parts are not separated by some special
character. For example, in some places strings have to be completed
that are formed ‘LikeThis’ (i.e. the separate parts are determined by
a leading uppercase letter) or maybe one has to complete strings with
trailing numbers. Here one could use the simple form with only one
anchor as in:
compadd -M ’r:|[A-Z0-9]=* r:|=*’ LikeTHIS FooHoo 5foo123 5bar234
But with this, the string ‘H’ would neither complete to ‘FooHoo’ nor
to ‘LikeTHIS’ because in each case there is an uppercase letter before
the ‘H’ and that is matched by the anchor. Likewise, a ‘2’ would not
be completed. In both cases this could be changed by using
‘r:|[A-Z0-9]=**’, but then ‘H’ completes to both ‘LikeTHIS’ and
‘FooHoo’ and a ‘2’ matches the other strings because characters can be
inserted before every uppercase letter and digit. To avoid this one
would use:
compadd -M ’r:[^A-Z0-9]||[A-Z0-9]=** r:|=*’ \
LikeTHIS FooHoo foo123 bar234
By using these two anchors, a ‘H’ matches only uppercase ‘H’s that are
immediately preceded by something matching the left anchor
‘[^A-Z0-9]’. The effect is, of course, that ‘H’ matches only the
string ‘FooHoo’, a ‘2’ matches only ‘bar234’ and so on.
When using the completion system (see zshcompsys(1)), users can define
match specifications that are to be used for specific contexts by
using the matcher and matcher-list styles. The values for the latter
will be used everywhere.
COMPLETION WIDGET EXAMPLE
The first step is to define the widget:
zle -C complete complete-word complete-files
Then the widget can be bound to a key using the bindkey builtin com-
mand:
bindkey ’^X\t’ complete
After that the shell function complete-files will be invoked after
typing control-X and TAB. The function should then generate the
matches, e.g.:
complete-files () { compadd - * }
This function will complete files in the current directory matching
ZSHCOMPSYS(1) ZSHCOMPSYS(1)
the current word.
NAME
zshcompsys - zsh completion system
DESCRIPTION
This describes the shell code for the new completion system. It con-
sists of various shell functions; those beginning ‘comp’ are to be
called directly, while those beginning ‘_’ are called by the comple-
tion code. The shell functions of the second set, which implement
completion behaviour and may be bound to keystrokes, are referred to
as ‘widgets’.
INITIALIZATION
If the system was installed completely, it should be enough to call
the shell function compinit from your initialization file; see the
next section. However, the function compinstall can be run by a user
to configure various aspects of the completion system.
Usually, compinstall will insert code into .zshrc, although if that is
not writable it will save it in another file and tell you that file’s
location. Note that it is up to you to make sure that the lines added
to .zshrc are actually run; you may, for example, need to move them to
an earlier place in the file if .zshrc usually returns early. So long
as you keep them all together (including the comment lines at the
start and finish), you can rerun compinstall and it will correctly
locate and modify these lines. Note, however, that any code you add
to this section by hand is likely to be lost if you rerun compinstall,
although lines using the command ‘zstyle’ should be gracefully han-
dled.
The new code will take effect next time you start the shell, or run
.zshrc by hand; there is also an option to make them take effect imme-
diately. However, if compinstall has removed definitions, you will
need to restart the shell to see the changes.
To run compinstall you will need to make sure it is in a directory
mentioned in your fpath parameter, which should already be the case if
zsh was properly configured as long as your startup files do not
remove the appropriate directories from fpath. Then it must be
autoloaded (‘autoload -U compinstall’ is recommended). You can abort
the installation any time you are being prompted for information, and
your .zshrc will not be altered at all; changes only take place right
at the end, where you are specifically asked for confirmation.
Use of compinit
This section describes the use of compinit to initialize completion
for the current session when called directly; if you have run compin-
stall it will be called automatically from your .zshrc.
To initialize the system, the function compinit should be in a direc-
tory mentioned in the fpath parameter, and should be autoloaded
(‘autoload -U compinit’ is recommended), and then run simply as
‘compinit’. This will define a few utility functions, arrange for all
the necessary shell functions to be autoloaded, and will then
re-define all widgets that do completion to use the new system. If
you use the menu-select widget, which is part of the zsh/complist mod-
ule, you should make sure that that module is loaded before the call
to compinit so that that widget is also re-defined. If completion
styles (see below) are set up to perform expansion as well as comple-
tion by default, and the TAB key is bound to expand-or-complete,
compinit will rebind it to complete-word; this is necessary to use the
correct form of expansion.
Should you need to use the original completion commands, you can still
bind keys to the old widgets by putting a ‘.’ in front of the widget
name, e.g. ‘.expand-or-complete’.
To speed up the running of compinit, it can be made to produce a
dumped configuration that will be read in on future invocations; this
is the default, but can be turned off by calling compinit with the
option -D. The dumped file is .zcompdump in the same directory as the
startup files (i.e. $ZDOTDIR or $HOME); alternatively, an explicit
file name can be given by ‘compinit -d dumpfile’. The next invocation
of compinit will read the dumped file instead of performing a full
initialization.
If the number of completion files changes, compinit will recognise
this and produce a new dump file. However, if the name of a function
or the arguments in the first line of a #compdef function (as
described below) change, it is easiest to delete the dump file by hand
so that compinit will re-create it the next time it is run. The check
performed to see if there are new functions can be omitted by giving
the option -C. In this case the dump file will only be created if
there isn’t one already.
The dumping is actually done by another function, compdump, but you
will only need to run this yourself if you change the configuration
(e.g. using compdef) and then want to dump the new one. The name of
the old dumped file will be remembered for this purpose.
If the parameter _compdir is set, compinit uses it as a directory
where completion functions can be found; this is only necessary if
they are not already in the function search path.
For security reasons compinit also checks if the completion system
would use files not owned by root or by the current user, or files in
directories that are world- or group-writable or that are not owned by
root or by the current user. If such files or directories are found,
compinit will ask if the completion system should really be used. To
avoid these tests and make all files found be used without asking, use
the option -u, and to make compinit silently ignore all insecure files
and directories use the option -i. This security check is skipped
entirely when the -C option is given.
The security check can be retried at any time by running the function
compaudit. This is the same check used by compinit, but when it is
executed directly any changes to fpath are made local to the function
so they do not persist. The directories to be checked may be passed
as arguments; if none are given, compaudit uses fpath and _compdir to
find completion system directories, adding missing ones to fpath as
necessary. To force a check of exactly the directories currently
named in fpath, set _compdir to an empty string before calling compau-
dit or compinit.
Autoloaded files
The convention for autoloaded functions used in completion is that
they start with an underscore; as already mentioned, the fpath/FPATH
parameter must contain the directory in which they are stored. If zsh
was properly installed on your system, then fpath/FPATH automatically
contains the required directories for the standard functions.
For incomplete installations, if compinit does not find enough files
beginning with an underscore (fewer than twenty) in the search path,
it will try to find more by adding the directory _compdir to the
search path. If that directory has a subdirectory named Base, all
subdirectories will be added to the path. Furthermore, if the subdi-
rectory Base has a subdirectory named Core, compinit will add all sub-
directories of the subdirectories is to the path: this allows the
functions to be in the same format as in the zsh source distribution.
When compinit is run, it searches all such files accessible via
fpath/FPATH and reads the first line of each of them. This line
should contain one of the tags described below. Files whose first
line does not start with one of these tags are not considered to be
part of the completion system and will not be treated specially.
The tags are:
#compdef names... [ -[pP] patterns... [ -N names... ] ]
The file will be made autoloadable and the function defined in
it will be called when completing names, each of which is
either the name of a command whose arguments are to be com-
pleted or one of a number of special contexts in the form -con-
text- described below.
Each name may also be of the form ‘cmd=service’. When complet-
ing the command cmd, the function typically behaves as if the
command (or special context) service was being completed
instead. This provides a way of altering the behaviour of
functions that can perform many different completions. It is
implemented by setting the parameter $service when calling the
function; the function may choose to interpret this how it
wishes, and simpler functions will probably ignore it.
If the #compdef line contains one of the options -p or -P, the
words following are taken to be patterns. The function will be
called when completion is attempted for a command or context
that matches one of the patterns. The options -p and -P are
used to specify patterns to be tried before or after other
completions respectively. Hence -P may be used to specify
default actions.
The option -N is used after a list following -p or -P; it spec-
ifies that remaining words no longer define patterns. It is
possible to toggle between the three options as many times as
necessary.
#compdef -k style key-sequences...
This option creates a widget behaving like the builtin widget
style and binds it to the given key-sequences, if any. The
style must be one of the builtin widgets that perform comple-
tion, namely complete-word, delete-char-or-list, expand-or-com-
plete, expand-or-complete-prefix, list-choices, menu-complete,
menu-expand-or-complete, or reverse-menu-complete. If the
zsh/complist module is loaded (see zshmodules(1)) the widget
menu-select is also available.
When one of the key-sequences is typed, the function in the
file will be invoked to generate the matches. Note that a key
will not be re-bound if if it already was (that is, was bound
to something other than undefined-key). The widget created has
the same name as the file and can be bound to any other keys
using bindkey as usual.
#compdef -K widget-name style key-sequences ...
This is similar to -k except that only one key-sequences argu-
ment may be given for each widget-name style pair. However,
the entire set of three arguments may be repeated with a dif-
ferent set of arguments. Note in particular that the wid-
get-name must be distinct in each set. If it does not begin
with ‘_’ this will be added. The widget-name should not clash
with the name of any existing widget: names based on the name
of the function are most useful. For example,
#compdef -K _foo_complete complete-word "^X^C" \
_foo_list list-choices "^X^D"
(all on one line) defines a widget _foo_complete for comple-
tion, bound to ‘^X^C’, and a widget _foo_list for listing,
bound to ‘^X^D’.
#autoload [ options ]
Functions with the #autoload tag are marked for autoloading but
are not otherwise treated specially. Typically they are to be
called from within one of the completion functions. Any
options supplied will be passed to the autoload builtin; a typ-
ical use is +X to force the function to be loaded immediately.
Note that the -U flag is always added implicitly.
The # is part of the tag name and no white space is allowed after it.
The #compdef tags use the compdef function described below; the main
difference is that the name of the function is supplied implicitly.
Note also that the functions for the completion system assume that the
KSH_AUTOLOAD option is not set. They cannot be loaded if it is set.
To avoid having to unset KSH_AUTOLOAD, you can instead use one or more
zwc file(s) that have been created with the command zcompile -z to
load the functions for the completion system; see zshbuiltins(1).
This forces the functions to be autoloaded the way zsh normally loads
functions.
The special contexts for which completion functions can be defined
are:
-array-value-
The right hand side of an array-assignment (‘foo=(...)’)
-brace-parameter-
The name of a parameter expansion within braces (‘${...}’)
-assign-parameter-
The name of a parameter in an assignment, i.e. on the left hand
side of an ‘=’
-command-
A word in command position
-condition-
A word inside a condition (‘[[...]]’)
-default-
Any word for which no other completion is defined
-equal-
A word beginning with an equals sign
-first-
This is tried before any other completion function. The func-
tion called may set the _compskip parameter to one of various
values: all: no further completion is attempted; a string con-
taining the substring patterns: no pattern completion functions
will be called; a string containing default: the function for
the ‘-default-’ context will not be called, but functions
defined for commands will
-math- Inside mathematical contexts, such as ‘((...))’
-parameter-
The name of a parameter expansion (‘$...’)
-redirect-
The word after a redirection operator.
-subscript-
The contents of a parameter subscript.
-tilde-
After an initial tilde (‘~’), but before the first slash in the
word.
-value-
On the right hand side of an assignment.
Default implementations are supplied for each of these contexts. In
most cases the context -context- is implemented by a corresponding
function _context, for example the context ‘-tilde-’ and the function
‘_tilde’).
The contexts -redirect- and -value- allow extra context-specific
information. (Internally, this is handled by the functions for each
context calling the function _dispatch.) The extra information is
added separated by commas.
For the -redirect- context, the extra information is in the form
‘-redirect-,op,command’, where op is the redirection operator and com-
mand is the name of the command on the line. If there is no command
on the line yet, the command field will be empty.
For the -value- context, the form is ‘-value-,name,command’, where
name is the name of the parameter. In the case of elements of an
associative array, for example ‘assoc=(key <TAB>’, name is expanded to
‘name-key’. In certain special contexts, such as completing after
‘make CFLAGS=’, the command part gives the name of the command, here
make; otherwise it is empty.
It is not necessary to define fully specific completions as the func-
tions provided will try to generate completions by progressively
replacing the elements with ‘-default-’. For example, when completing
after ‘foo=<TAB>’, _value will try the names ‘-value-,foo,’ (note the
empty command part), ‘-value-,foo,-default-’
and‘-value-,-default-,-default-’, in that order, until it finds a
function to handle the context.
As an example:
compdef ’_files -g "*.log"’ ’-redirect-,2>,-default-’
completes files matching ‘*.log’ after ‘2> <TAB>’ for any command with
no more specific handler defined.
Also:
compdef _foo -value-,-default-,-default-
specifies that _foo provides completions for the values of parameters
for which no special function has been defined. This is usually han-
dled by the function _value itself.
The same lookup rules are used when looking up styles (as described
below); for example
zstyle ’:completion:*:*:-redirect-,2>,*:*’ file-patterns ’*.log’
is another way to make completion after ‘2> <TAB>’ complete files
matching ‘*.log’.
Functions
The following function is defined by compinit and may be called
directly.
compdef [ -an ] function names... [ -[pP] patterns... [ -N names... ]
]
compdef -d names...
compdef -k [ -an ] function style key-sequences...
compdef -K [ -an ] function name style key-sequences ...
The first form defines the function to call for completion in
the given contexts as described for the #compdef tag above.
Alternatively, all the arguments may have the form ‘cmd=ser-
vice’. Here service should already have been defined by
‘cmd1=service’ lines in #compdef files, as described above.
The argument for cmd will be completed in the same way as ser-
vice.
The function argument may alternatively be a string containing
any shell code. The string will be executed using the eval
builtin command to generate completions. This provides a way
of avoiding having to define a new completion function. For
example, to complete files ending in ‘.h’ as arguments to the
command foo:
compdef ’_files -g "*.h"’ foo
The option -n prevents any completions already defined for the
command or context from being overwritten.
The option -d deletes any completion defined for the command or
contexts listed.
The names may also contain -p, -P and -N options as described
for the #compdef tag. The effect on the argument list is iden-
tical, switching between definitions of patterns tried ini-
tially, patterns tried finally, and normal commands and con-
texts.
The parameter $_compskip may be set by any function defined for
a pattern context. If it is set to a value containing the sub-
string ‘patterns’ none of the pattern-functions will be called;
if it is set to a value containing the substring ‘all’, no
other function will be called.
The form with -k defines a widget with the same name as the
function that will be called for each of the key-sequences;
this is like the #compdef -k tag. The function should generate
the completions needed and will otherwise behave like the
builtin widget whose name is given as the style argument. The
widgets usable for this are: complete-word,
delete-char-or-list, expand-or-complete, expand-or-com-
plete-prefix, list-choices, menu-complete, menu-expand-or-com-
plete, and reverse-menu-complete, as well as menu-select if the
zsh/complist module is loaded. The option -n prevents the key
being bound if it is already to bound to something other than
undefined-key.
The form with -K is similar and defines multiple widgets based
on the same function, each of which requires the set of three
arguments name, style and key-sequences, where the latter two
are as for -k and the first must be a unique widget name begin-
ning with an underscore.
Wherever applicable, the -a option makes the function autoload-
able, equivalent to autoload -U function.
The function compdef can be used to associate existing completion
functions with new commands. For example,
compdef _pids foo
uses the function _pids to complete process IDs for the command foo.
Note also the _gnu_generic function described below, which can be used
to complete options for commands that understand the ‘--help’ option.
COMPLETION SYSTEM CONFIGURATION
This section gives a short overview of how the completion system
works, and then more detail on how users can configure how and when
matches are generated.
Overview
When completion is attempted somewhere on the command line the comple-
tion system first works out the context. This takes account of a num-
ber of things including the command word (such as ‘grep’ or ‘zsh’) and
options to which the current word may be an argument (such as the ‘-o’
option to zsh which takes a shell option as an argument).
This context information is condensed into a string consisting of mul-
tiple fields separated by colons, referred to simply as ‘the context’
in the remainder of the documentation. This is used to look up
styles, context-sensitive options that can be used to configure the
completion system. The context used for lookup may vary during the
same call to the completion system.
The context string always consists of the following fields, separated
by colons and with a leading colon before the first:
· The literal string completion, saying that this style is used
by the completion system. This distinguishes the context from
those used by, for example, zle widgets and ZFTP functions.
· The function, if completion is called from a named widget
rather than through the normal completion system. Typically
this is blank, but it is set by special widgets such as pre-
dict-on and the various functions in the Widget directory of
the distribution to the name of that function, often in an
abbreviated form.
· The completer currently active, the name of the function with-
out the leading underscore. A ‘completer’ is in overall con-
trol of how completion is to be performed; ‘complete’ is the
simplest, but other completers exist to perform related tasks
such as correction, or to modify the behaviour of a later com-
pleter. See the section ‘Control Functions’ below for more
information.
· The command or a special -context-, just at it appears follow-
ing the #compdef tag or the compdef function. Completion func-
tions for commands that have sub-commands usually modify this
field to contain the name of the command followed by a minus
sign and the sub-command. For example, the completion function
for the cvs command sets this field to cvs-add when completing
arguments to the add subcommand.
· The argument; this indicates which command line or option argu-
ment we are completing. For command arguments this generally
takes the form argument-n, where n is the number of the argu-
ment, and for arguments to options the form option-opt-n where
n is the number of the argument to option opt. However, this
is only the case if the command line is parsed with standard
UNIX-style options and arguments, so many completions do not
set this.
· The tag. Tags are used to discriminate between the types of
matches a completion function can generate in a certain context
and are described further below.
As an example, the context name
:completion::complete:dvips:option-o-1:files
says that normal completion was attempted as the first argument to the
option -o of the command dvips:
dvips -o ...
and the completion function will generate filenames.
Each type of completion the system can perform in a given context is
described by a ‘tag’, a short descriptive string such as files in the
example above. Any completion function may use any tag name it likes,
but a list of the more common ones is given below.
Usually completion will be tried by all possible tags in an order
given by the completion function. However, this can be altered by
using the tag-order style. Completion is then restricted to the list
of given tags in the given order.
The _complete_help bindable command shows all the contexts and tags
available for completion at a particular point. This provides an easy
way of finding information for tag-order and other styles. It is
described in the section ‘Bindable Commands’ below.
Styles determine such things as how the matches are generated, simi-
larly to shell options but with much more control. They can have any
number of strings as their value. They are defined with the zstyle
builtin command (see zshmodules(1)).
When looking up styles the completion system uses full context names,
including the tag. Looking up the value of a style therefore consists
of two things: the context, which may be matched as a pattern, and
the name of the style itself, which must be given exactly.
For example, many completion functions can generate matches in a sim-
ple and a verbose form and use the verbose style to decide which form
should be used. To make all such functions use the verbose form, put
zstyle ’:completion:*’ verbose yes
in a startup file (probably .zshrc). This gives the verbose style the
value yes in every context inside the completion system, unless that
context has a more specific definition. It is best to avoid giving
the context as ‘*’ in case the style has some meaning outside the com-
pletion system.
Many such general purpose styles can be configured simply by using the
compinstall function.
A more specific example of the use of the verbose style is by the com-
pletion for the kill builtin. If the style is set, the builtin lists
full job texts and process command lines; otherwise it shows the bare
job numbers and PIDs. To turn the style off for this use only:
zstyle ’:completion:*:*:kill:*’ verbose no
For even more control, the style can use one of the tags ‘jobs’ or
‘processes’. To turn off verbose display only for jobs:
zstyle ’:completion:*:*:kill:*:jobs’ verbose no
The -e option to zstyle even allows completion function code to appear
as the argument to a style; this requires some understanding of the
internals of completion functions (see see zshcompwid(1))). For exam-
ple:
zstyle -e ’:completion:*’ completer ’
if [[ $words[1] = cvs ]]; then
reply=(_complete)
else
reply=(_complete _approximate)
fi’
uses the value ‘_complete’ for the completer style in most contexts,
but the value ‘_complete _approximate’ when the first word on the com-
mand line is ‘cvs’. This is probably more conveniently done by speci-
fying the style for two different contexts. This form can be slow and
should be avoided for commonly examined styles such as menu and
list-rows-first.
Note that the order in which styles are defined does not matter; the
style mechanism uses the most specific possible match for a particular
style to determine the set of values. More precisely, strings are
preferred over patterns (for example, ‘:completion::complete:foo’ is
more specific than ‘:completion::complete:*’), and longer patterns are
preferred over shorter patterns.
Style names like those of tags are arbitrary and depend on the comple-
tion function. However, the following two sections list some of the
most common tags and styles.
Standard Tags
Some of the following are only used when looking up particular styles
and do not refer to a type of match.
accounts
used to look up the users-hosts style
all-expansions
used by the _expand completer when adding the single string
containing all possible expansions
all-files
for the names of all files (as distinct from a particular sub-
set, see the globbed-files tag).
arguments
for arguments to a command
arrays for names of array parameters
association-keys
for keys of associative arrays; used when completing inside a
subscript to a parameter of this type
bookmarks
when completing bookmarks (e.g. for URLs and the zftp function
suite)
builtins
for names of builtin commands
characters
for single characters in arguments of commands such as stty.
Also used when completing character classes after an opening
bracket
colormapids
for X colormap ids
colors for color names
commands
for names of external commands. Also used by complex commands
such as cvs when completing names subcommands.
contexts
for contexts in arguments to the zstyle builtin command
corrections
used by the _approximate and _correct completers for possible
corrections
cursors
for cursor names used by X programs
default
used in some contexts to provide a way of supplying a default
when more specific tags are also valid. Note that this tag is
used when only the function field of the context name is set
descriptions
used when looking up the value of the format style to generate
descriptions for types of matches
devices
for names of device special files
directories
for names of directories
directory-stack
for entries in the directory stack
displays
for X display names
domains
for network domains
expansions
used by the _expand completer for individual words (as opposed
to the complete set of expansions) resulting from the expansion
of a word on the command line
extensions
for X server extensions
file-descriptors
for numbers of open file descriptors
files the generic file-matching tag used by functions completing
filenames
fonts for X font names
fstypes
for file system types (e.g. for the mount command)
functions
names of functions --- normally shell functions, although cer-
tain commands may understand other kinds of function
globbed-files
for filenames when the name has been generated by pattern
matching
groups for names of user groups
history-words
for words from the history
hosts for hostnames
indexes
for array indexes
jobs for jobs (as listed by the ‘jobs’ builtin)
interfaces
for network interfaces
keymaps
for names of zsh keymaps
keysyms
for names of X keysyms
libraries
for names of system libraries
limits for system limits
local-directories
for names of directories that are subdirectories of the current
working directory when completing arguments of cd and related
builtin commands (compare path-directories)
manuals
for names of manual pages
mailboxes
for e-mail folders
maps for map names (e.g. NIS maps)
messages
used to look up the format style for messages
modifiers
for names of X modifiers
modules
for modules (e.g. zsh modules)
my-accounts
used to look up the users-hosts style
named-directories
for named directories (you wouldn’t have guessed that, would
you?)
names for all kinds of names
newsgroups
for USENET groups
nicknames
for nicknames of NIS maps
options
for command options
original
used by the _approximate, _correct and _expand completers when
offering the original string as a match
other-accounts
used to look up the users-hosts style
packages
for packages (e.g. rpm or installed Debian packages)
parameters
for names of parameters
path-directories
for names of directories found by searching the cdpath array
when completing arguments of cd and related builtin commands
(compare local-directories)
paths used to look up the values of the expand, ambiguous and spe-
cial-dirs styles
pods for perl pods (documentation files)
ports for communication ports
prefixes
for prefixes (like those of a URL)
printers
for print queue names
processes
for process identifiers
processes-names
used to look up the command style when generating the names of
processes for killall
sequences
for sequences (e.g. mh sequences)
sessions
for sessions in the zftp function suite
signals
for signal names
strings
for strings (e.g. the replacement strings for the cd builtin
command)
styles for styles used by the zstyle builtin command
suffixes
for filename extensions
tags for tags (e.g. rpm tags)
targets
for makefile targets
time-zones
for time zones (e.g. when setting the TZ parameter)
types for types of whatever (e.g. address types for the xhost com-
mand)
urls used to look up the urls and local styles when completing URLs
users for usernames
values for one of a set of values in certain lists
variant
used by _pick_variant to look up the command to run when deter-
mining what program is installed for a particular command name.
visuals
for X visuals
warnings
used to look up the format style for warnings
widgets
for zsh widget names
windows
for IDs of X windows
zsh-options
for shell options
Standard Styles
Note that the values of several of these styles represent boolean val-
ues. Any of the strings ‘true’, ‘on’, ‘yes’, and ‘1’ can be used for
the value ‘true’ and any of the strings ‘false’, ‘off’, ‘no’, and ‘0’
for the value ‘false’. The behavior for any other value is undefined
except where explicitly mentioned. The default value may be either
true or false if the style is not set.
Some of these styles are tested first for every possible tag corre-
sponding to a type of match, and if no style was found, for the
default tag. The most notable styles of this type are menu, list-col-
ors and styles controlling completion listing such as list-packed and
last-prompt). When tested for the default tag, only the function
field of the context will be set so that a style using the default tag
will normally be defined along the lines of:
zstyle ’:completion:*:default’ menu ...
accept-exact
This is tested for the default tag in addition to the tags
valid for the current context. If it is set to ‘true’ and any
of the trial matches is the same as the string on the command
line, this match will immediately be accepted (even if it would
otherwise be considered ambiguous).
When completing pathnames (where the tag used is ‘paths’) this
style accepts any number of patterns as the value in addition
to the boolean values. Pathnames matching one of these pat-
terns will be accepted immediately even if the command line
contains some more partially typed pathname components and
these match no file under the directory accepted.
This style is also used by the _expand completer to decide if
words beginning with a tilde or parameter expansion should be
expanded. For example, if there are parameters foo and foobar,
the string ‘$foo’ will only be expanded if accept-exact is set
to ‘true’; otherwise the completion system will be allowed to
complete $foo to $foobar. If the style is set to ‘continue’,
_expand will add the expansion as a match and the completion
system will also be allowed to continue.
add-space
This style is used by the _expand completer. If it is true
(the default), a space will be inserted after all words result-
ing from the expansion, or a slash in the case of directory
names. If the value is ‘file’, the completer will only add a
space to names of existing files. Either a boolean true or the
value ‘file’ may be combined with ‘subst’, in which case the
completer will not add a space to words generated from the
expansion of a substitution of the form ‘$(...)’ or ‘${...}’.
The _prefix completer uses this style as a simple boolean value
to decide if a space should be inserted before the suffix.
ambiguous
This applies when completing non-final components of filename
paths, in other words those with a trailing slash. If it is
set, the cursor is left after the first ambiguous component,
even if menu completion is in use. The style is always tested
with the paths tag.
assign-list
When completing after an equals sign that is being treated as
an assignment, the completion system normally completes only
one filename. In some cases the value may be a list of file-
names separated by colons, as with PATH and similar parameters.
This style can be set to a list of patterns matching the names
of such parameters.
The default is to complete lists when the word on the line
already contains a colon.
auto-description
If set, this style’s value will be used as the description for
options that are not described by the completion functions, but
that have exactly one argument. The sequence ‘%d’ in the value
will be replaced by the description for this argument. Depend-
ing on personal preferences, it may be useful to set this style
to something like ‘specify: %d’. Note that this may not work
for some commands.
avoid-completer
This is used by the _all_matches completer to decide if the
string consisting of all matches should be added to the list
currently being generated. Its value is a list of names of
completers. If any of these is the name of the completer that
generated the matches in this completion, the string will not
be added.
The default value for this style is ‘_expand _old_list _correct
_approximate’, i.e. it contains the completers for which a
string with all matches will almost never be wanted.
cache-path
This style defines the path where any cache files containing
dumped completion data are stored. It defaults to ‘$ZDOT-
DIR/.zcompcache’, or ‘$HOME/.zcompcache’ if $ZDOTDIR is not
defined. The completion cache will not be used unless the
use-cache style is set.
cache-policy
This style defines the function that will be used to determine
whether a cache needs rebuilding. See the section on the
_cache_invalid function below.
call-command
This style is used in the function for commands such as make
and ant where calling the command directly to generate matches
suffers problems such as being slow or, as in the case of make
can potentially causes actions in the makefile to be executed.
If it is set to ‘true’ the command is called to generate
matches. The default value of this style is ‘false’.
command
In many places, completion functions need to call external com-
mands to generate the list of completions. This style can be
used to override the command that is called in some such cases.
The elements of the value are joined with spaces to form a com-
mand line to execute. The value can also start with a hyphen,
in which case the usual command will be added to the end; this
is most useful for putting ‘builtin’ or ‘command’ in front to
make sure the appropriate version of a command is called, for
example to avoid calling a shell function with the same name as
an external command.
As an example, the completion function for process IDs uses
this style with the processes tag to generate the IDs to com-
plete and the list of processes to display (if the verbose
style is ‘true’). The list produced by the command should look
like the output of the ps command. The first line is not dis-
played, but is searched for the string ‘PID’ (or ‘pid’) to find
the position of the process IDs in the following lines. If the
line does not contain ‘PID’, the first numbers in each of the
other lines are taken as the process IDs to complete.
Note that the completion function generally has to call the
specified command for each attempt to generate the completion
list. Hence care should be taken to specify only commands that
take a short time to run, and in particular to avoid any that
may never terminate.
commands
This is used by the function completing sub-commands for the
system initialisation scripts (residing in /etc/init.d or some-
where not too far away from that). Its values give the default
commands to complete for those commands for which the comple-
tion function isn’t able to find them out automatically. The
default for this style are the two strings ‘start’ and ‘stop’.
complete
This is used by the _expand_alias function when invoked as a
bindable command. If it set to ‘true’ and the word on the com-
mand line is not the name of an alias, matching alias names
will be completed.
completer
The strings given as the value of this style provide the names
of the completer functions to use. The available completer
functions are described in the section ‘Control Functions’
below.
Each string may be either the name of a completer function or a
string of the form ‘function:name’. In the first case the com-
pleter field of the context will contain the name of the com-
pleter without the leading underscore and with all other under-
scores replaced by hyphens. In the second case the function is
the name of the completer to call, but the context will contain
the user-defined name in the completer field of the context.
If the name starts with a hyphen, the string for the context
will be build from the name of the completer function as in the
first case with the name appended to it. For example:
zstyle ’:completion:*’ completer _complete _complete:-foo
Here, completion will call the _complete completer twice, once
using ‘complete’ and once using ‘complete-foo’ in the completer
field of the context. Normally, using the same completer more
than once only makes sense when used with the ‘functions:name’
form, because otherwise the context name will be the same in
all calls to the completer; possible exceptions to this rule
are the _ignored and _prefix completers.
The default value for this style is ‘_complete _ignored’: only
completion will be done, first using the ignored-patterns style
and the $fignore array and then without ignoring matches.
condition
This style is used by the _list completer function to decide if
insertion of matches should be delayed unconditionally. The
default is ‘true’.
disabled
If this is set to ‘true’, the _expand_alias completer and bind-
able command will try to expand disabled aliases, too. The
default is ‘false’.
disable-stat
This is used with an empty tag by the _cvs function to decide
whether the zsh/stat module should be used to generate names of
modified files in the appropriate places (this is its only
use). If the style is set, completion will use the ls command.
domains
A list of names of network domains for completion. If this is
not set, domain names will be taken from the file
/etc/resolv.conf.
expand This style is used when completing strings consisting of multi-
ple parts, such as path names.
If one of its values is the string ‘prefix’, the partially
typed word from the line will be expanded as far as possible
even if trailing parts cannot be completed.
If one of its values is the string ‘suffix’, matching names for
components after the first ambiguous one will also be added.
This means that the resulting string is the longest unambiguous
string possible. However, menu completion can be used to cycle
through all matches.
fake This style may be set for any completion context. It specifies
additional strings that will always be completed in that con-
text. The form of each string is ‘value:description’; the
colon and description may be omitted, but any literal colons in
value must be quoted with a backslash. Any description pro-
vided is shown alongside the value in completion listings.
It is important to use a sufficiently restrictive context when
specifying fake strings. Note that the styles fake-files and
fake-parameters provide additional features when completing
files or parameters.
fake-files
This style is used when completing files and looked up without
a tag. Its values are of the form ‘dir:names...’. This will
add the names (strings separated by spaces) as possible matches
when completing in the directory dir, even if no such files
really exist.
This can be useful on systems that support special filesystems
whose top-level pathnames can not be listed or generated with
glob patterns. It can also be used for directories for which
one does not have read permission.
fake-parameters
This is used by the completion function for parameter names.
Its values are names of parameters that might not yet be set
but should be completed nonetheless. Each name may also be
followed by a colon and a string specifying the type of the
parameter (like ‘scalar’, ‘array’ or ‘integer’). If the type
is given, the name will only be completed if parameters of that
type are required in the particular context. Names for which
no type is specified will always be completed.
file-patterns
This is used by the standard function for completing filenames,
_files. If the style is unset up to three tags are offered,
‘globbed-files’,‘directories’ and ‘all-files’, depending on the
types of files expected by the caller of _files. The first
two (‘globbed-files’ and ‘directories’) are normally offered
together to make it easier to complete files in sub-directo-
ries.
The file-patterns style provides alternatives to the default
tags, which are not used. Its value consists of elements of
the form ‘pattern:tag’; each string may contain any number of
such specifications separated by spaces.
The pattern is a pattern that is to be used to generate file-
names. Any occurrence of the sequence ‘%p’ is replaced by any
pattern(s) passed by the function calling _files. Colons in
the pattern must be preceded by a backslash to make them dis-
tinguishable from the colon before the tag. If more than one
pattern is needed, the patterns can be given inside braces,
separated by commas.
The tags of all strings in the value will be offered by _files
and used when looking up other styles. Any tags in the same
word will be offered at the same time and before later words.
If no ‘:tag’ is given the ‘files’ tag will be used.
The tag may also be followed by an optional second colon and a
description, which will be used for the ‘%d’ in the value of
the format style (if that is set) instead of the default
description supplied by the completion function. If the
description given here contains itself a ‘%d’, that is replaced
with the description supplied by the completion function.
For example, to make the rm command first complete only names
of object files and then the names of all files if there is no
matching object file:
zstyle ’:completion:*:*:rm:*’ file-patterns \
’*.o:object-files’ ’%p:all-files’
To alter the default behaviour of file completion --- offer
files matching a pattern and directories on the first attempt,
then all files --- to offer only matching files on the first
attempt, then directories, and finally all files:
zstyle ’:completion:*’ file-patterns \
’%p:globbed-files’ ’*(-/):directories’ ’*:all-files’
This works even where there is no special pattern: _files
matches all files using the pattern ‘*’ at the first step and
stops when it sees this pattern. Note also it will never try a
pattern more than once for a single completion attempt.
During the execution of completion functions, the EXTENDED_GLOB
option is in effect, so the characters ‘#’, ‘~’ and ‘^’ have
special meanings in the patterns.
file-sort
The standard filename completion function uses this style with-
out a tag to determine in which order the names should be
listed; menu completion will cycle through them in the same
order. The possible values are: ‘size’ to sort by the size of
the file; ‘links’ to sort by the number of links to the file;
‘modification’ (or ‘time’ or ‘date’) to sort by the last modi-
fication time; ‘access’ to sort by the last access time; and
‘inode’ (or ‘change’) to sort by the last inode change time.
If the style is set to any other value, or is unset, files will
be sorted alphabetically by name. If the value contains the
string ‘reverse’, sorting is done in the opposite order.
filter This is used by the LDAP plugin for e-mail address completion
to specify the attributes to match against when filtering
entries. So for example, if the style is set to ‘sn’, matching
is done against surnames. Standard LDAP filtering is used so
normal completion matching is bypassed. If this style is not
set, the LDAP plugin is skipped. You may also need to set the
command style to specify how to connect to your LDAP server.
force-list
This forces a list of completions to be shown at any point
where listing is done, even in cases where the list would usu-
ally be suppressed. For example, normally the list is only
shown if there are at least two different matches. By setting
this style to ‘always’, the list will always be shown, even if
there is only a single match that will immediately be accepted.
The style may also be set to a number. In this case the list
will be shown if there are at least that many matches, even if
they would all insert the same string.
This style is tested for the default tag as well as for each
tag valid for the current completion. Hence the listing can be
forced only for certain types of match.
format If this is set for the descriptions tag, its value is used as a
string to display above matches in completion lists. The
sequence ‘%d’ in this string will be replaced with a short
description of what these matches are. This string may also
contain the sequences to specify output attributes, such as
‘%B’, ‘%S’ and ‘%{...%}’.
The style is tested with each tag valid for the current comple-
tion before it is tested for the descriptions tag. Hence dif-
ferent format strings can be defined for different types of
match.
Note also that some completer functions define additional
‘%’-sequences. These are described for the completer functions
that make use of them.
Some completion functions display messages that may be cus-
tomised by setting this style for the messages tag. Here, the
‘%d’ is replaced with a message given by the completion func-
tion.
Finally, the format string is looked up with the warnings tag,
for use when no matches could be generated at all. In this
case the ‘%d’ is replaced with the descriptions for the matches
that were expected separated by spaces. The sequence ‘%D’ is
replaced with the same descriptions separated by newlines.
It is possible to use printf-style field width specifiers with
‘%d’ and similar escape sequences. This is handled by the
zformat builtin command from the zsh/zutil module, see zshmod-
ules(1).
glob This is used by the _expand completer. If it is set to ‘true’
(the default), globbing will be attempted on the words result-
ing from a previous substitution (see the substitute style) or
else the original string from the line.
global If this is set to ‘true’ (the default), the _expand_alias com-
pleter and bindable command will try to expand global aliases.
group-name
The completion system can group different types of matches,
which appear in separate lists. This style can be used to give
the names of groups for particular tags. For example, in com-
mand position the completion system generates names of builtin
and external commands, names of aliases, shell functions and
parameters and reserved words as possible completions. To have
the external commands and shell functions listed separately:
zstyle ’:completion:*:*:-command-:*:commands’ group-name commands
zstyle ’:completion:*:*:-command-:*:functions’ group-name functions
As a consequence, any match with the same tag will be displayed
in the same group.
If the name given is the empty string the name of the tag for
the matches will be used as the name of the group. So, to have
all different types of matches displayed separately, one can
just set:
zstyle ’:completion:*’ group-name ’’
All matches for which no group name is defined will be put in a
group named -default-.
group-order
This style is additional to the group-name style to specify the
order for display of the groups defined by that style (compare
tag-order, which determines which completions appear at all).
The groups named are shown in the given order; any other groups
are shown in the order defined by the completion function.
For example, to have names of builtin commands, shell functions
and external commands appear in that order when completing in
command position:
zstyle ’:completion:*:*:-command-:*’ group-order \
builtins functions commands
groups A list of names of UNIX groups. If this is not set, group
names are taken from the YP database or the file ‘/etc/group’.
hidden If this is set to true, matches for the given context will not
be listed, although any description for the matches set with
the format style will be shown. If it is set to ‘all’, not
even the description will be displayed.
Note that the matches will still be completed; they are just
not shown in the list. To avoid having matches considered as
possible completions at all, the tag-order style can be modi-
fied as described below.
hosts A list of names of hosts that should be completed. If this is
not set, hostnames are taken from the file ‘/etc/hosts’.
hosts-ports
This style is used by commands that need or accept hostnames
and network ports. The strings in the value should be of the
form ‘host:port’. Valid ports are determined by the presence
of hostnames; multiple ports for the same host may appear.
ignore-line
This is tested for each tag valid for the current completion.
If it is set to ‘true’, none of the words that are already on
the line will be considered as possible completions. If it is
set to ‘current’, the word the cursor is on will not be consid-
ered as a possible completion. The value ‘current-shown’ is
similar but only applies if the list of completions is cur-
rently shown on the screen. Finally, if the style is set to
‘other’, no word apart from the current one will be considered
as a possible completion.
The values ‘current’ and ‘current-shown’ are a bit like the
opposite of the accept-exact style: only strings with missing
characters will be completed.
Note that you almost certainly don’t want to set this to ‘true’
or ‘other’ for a general context such as ‘:completion:*’. This
is because it would disallow completion of, for example,
options multiple times even if the command in question accepts
the option more than once.
ignore-parents
The style is tested without a tag by the function completing
pathnames in order to determine whether to ignore the names of
directories already mentioned in the current word, or the name
of the current working directory. The value must include one
or both of the following strings:
parent The name of any directory whose path is already con-
tained in the word on the line is ignored. For example,
when completing after foo/../, the directory foo will
not be considered a valid completion.
pwd The name of the current working directory will not be
completed; hence, for example, completion after ../ will
not use the name of the current directory.
In addition, the value may include one or both of:
.. Ignore the specified directories only when the word on
the line contains the substring ‘../’.
directory
Ignore the specified directories only when names of
directories are completed, not when completing names of
files.
Excluded values act in a similar fashion to values of the
ignored-patterns style, so they can be restored to considera-
tion by the _ignored completer.
ignored-patterns
A list of patterns; any trial completion matching one of the
patterns will be excluded from consideration. The _ignored
completer can appear in the list of completers to restore the
ignored matches. This is a more configurable version of the
shell parameter $fignore.
Note that the EXTENDED_GLOB option is set during the execution
of completion functions, so the characters ‘#’, ‘~’ and ‘^’
have special meanings in the patterns.
insert This style is used by the _all_matches completer to decide
whether to insert the list of all matches unconditionally
instead of adding the list as another match.
insert-ids
When completing process IDs, for example as arguments to the
kill and wait builtins the name of a command may be converted
to the appropriate process ID. A problem arises when the pro-
cess name typed is not unique. By default (or if this style is
set explicitly to ‘menu’) the name will be converted immedi-
ately to a set of possible IDs, and menu completion will be
started to cycle through them.
If the value of the style is ‘single’, the shell will wait
until the user has typed enough to make the command unique
before converting the name to an ID; attempts at completion
will be unsuccessful until that point. If the value is any
other string, menu completion will be started when the string
typed by the user is longer than the common prefix to the cor-
responding IDs.
insert-tab
If this is set to ‘true’, the completion system will insert a
TAB character (assuming that was used to start completion)
instead of performing completion when there is no non-blank
character to the left of the cursor. If it is set to ‘false’,
completion will be done even there.
The value may also contain the substrings ‘pending’ or ‘pend-
ing=val’. In this case, the typed character will be inserted
instead of staring completion when there is unprocessed input
pending. If a val is given, completion will not be done if
there are at least that many characters of unprocessed input.
This is often useful when pasting characters into a terminal.
Note however, that it relies on the $PENDING special parameter
from the zsh/zle module being set properly which is not guaran-
teed on all platforms.
The default value of this style is ‘true’ except for completion
within vared builtin command where it is ‘false’.
insert-unambiguous
This is used by the _match and _approximate completers. These
completers are often used with menu completion since the word
typed may bear little resemblance to the final completion.
However, if this style is ‘true’, the completer will start menu
completion only if it could find no unambiguous initial string
at least as long as the original string typed by the user.
In the case of the _approximate completer, the completer field
in the context will already have been set to one of correct-num
or approximate-num, where num is the number of errors that were
accepted.
In the case of the _match completer, the style may also be set
to the string ‘pattern’. Then the pattern on the line is left
unchanged if it does not match unambiguously.
keep-prefix
This style is used by the _expand completer. If it is ‘true’,
the completer will try to keep a prefix containing a tilde or
parameter expansion. Hence, for example, the string ‘~/f*’
would be expanded to ‘~/foo’ instead of ‘/home/user/foo’. If
the style is set to ‘changed’ (the default), the prefix will
only be left unchanged if there were other changes between the
expanded words and the original word from the command line.
Any other value forces the prefix to be expanded uncondition-
ally.
The behaviour of expand when this style is true is to cause
_expand to give up when a single expansion with the restored
prefix is the same as the original; hence any remaining com-
pleters may be called.
last-prompt
This is a more flexible form of the ALWAYS_LAST_PROMPT option.
If it is true, the completion system will try to return the
cursor to the previous command line after displaying a comple-
tion list. It is tested for all tags valid for the current
completion, then the default tag. The cursor will be moved
back to the previous line if this style is ‘true’ for all types
of match. Note that unlike the ALWAYS_LAST_PROMPT option this
is independent of the numeric prefix argument.
list This style is used by the _history_complete_word bindable com-
mand. If it is set to ‘true’ it has no effect. If it is set
to ‘false’ matches will not be listed. This overrides the set-
ting of the options controlling listing behaviour, in particu-
lar AUTO_LIST. The context always starts with ‘:comple-
tion:history-words’.
list-colors
If the zsh/complist module is loaded, this style can be used to
set color specifications. This mechanism replaces the use of
the ZLS_COLORS and ZLS_COLOURS parameters described in the sec-
tion ‘The zsh/complist Module’ in zshmodules(1), but the syntax
is the same.
If this style is set for the default tag, the strings in the
value are taken as specifications that are to be used every-
where. If it is set for other tags, the specifications are
used only for matches of the type described by the tag. For
this to work best, the group-name style must be set to an empty
string.
In addition to setting styles for specific tags, it is also
possible to use group names specified explicitly by the
group-name tag together with the ‘(group)’ syntax allowed by
the ZLS_COLORS and ZLS_COLOURS parameters and simply using the
default tag.
It is possible to use any color specifications already set up
for the GNU version of the ls command:
zstyle ’:completion:*:default’ list-colors ${(s.:.)LS_COLORS}
The default colors are the same as for the GNU ls command and
can be obtained by setting the style to an empty string (i.e.
’’).
list-grouped
If this style is ‘true’ (the default), the completion system
will try to make certain completion listings more compact by
grouping matches. For example, options for commands that have
the same description (shown when the verbose style is set to
‘true’) will appear as a single entry. However, menu selection
can be used to cycle through all the matches.
list-packed
This is tested for each tag valid in the current context as
well as the default tag. If it is set to ‘true’, the corre-
sponding matches appear in listings as if the LIST_PACKED
option were set. If it is set to ‘false’, they are listed nor-
mally.
list-prompt
If this style is set for the default tag, completion lists that
don’t fit on the screen can be scrolled (see the description of
the zsh/complist module in zshmodules(1)). The value, if not
the empty string, will be displayed after every screenful and
the shell will prompt for a key press; if the style is set to
the empty string, a default prompt will be used.
The value may contain the escape sequences: ‘%l’ or ‘%L’, which
will be replaced by the number of the last line displayed and
the total number of lines; ‘%m’ or ‘%M’, the number of the
last match shown and the total number of matches; and ‘%p’ and
‘%P’, ‘Top’ when at the beginning of the list, ‘Bottom’ when at
the end and the position shown as a percentage of the total
length otherwise. In each case the form with the uppercase
letter will be replaced by a string of fixed width, padded to
the right with spaces, while the lowercase form will be
replaced by a variable width string. As in other prompt
strings, the escape sequences ‘%S’, ‘%s’, ‘%B’, ‘%b’, ‘%U’,
‘%u’ for entering and leaving the display modes standout, bold
and underline are also available, as is the form ‘%{...%}’ for
enclosing escape sequences which display with zero width.
list-rows-first
This style is tested in the same way as the list-packed style
and determines whether matches are to be listed in a rows-first
fashion as if the LIST_ROWS_FIRST option were set.
list-suffixes
This style is used by the function that completes filenames.
If it is true, and completion is attempted on a string contain-
ing multiple partially typed pathname components, all ambiguous
components will be shown. Otherwise, completion stops at the
first ambiguous component.
list-separator
The value of this style is used in completion listing to sepa-
rate the string to complete from a description when possible
(e.g. when completing options). It defaults to ‘--’ (two
hyphens).
local This is for use with functions that complete URLs for which the
corresponding files are available directly from the filing sys-
tem. Its value should consist of three strings: a hostname,
the path to the default web pages for the server, and the
directory name used by a user placing web pages within their
home area.
For example:
zstyle ’:completion:*’ local toast \
/var/http/public/toast public_html
Completion after ‘http://toast/stuff/’ will look for files in
the directory /var/http/public/toast/stuff, while completion
after ‘http://toast/~yousir/’ will look for files in the direc-
tory ~yousir/public_html.
mail-directory
If set, zsh will assume that mailbox files can be found in the
directory specified. It defaults to ‘~/Mail’.
match-original
This is used by the _match completer. If it is set to only,
_match will try to generate matches without inserting a ‘*’ at
the cursor position. If set to any other non-empty value, it
will first try to generate matches without inserting the ‘*’
and if that yields no matches, it will try again with the ‘*’
inserted. If it is unset or set to the empty string, matching
will only be performed with the ‘*’ inserted.
matcher
This style is tested separately for each tag valid in the cur-
rent context. Its value is added to any match specifications
given by the matcher-list style. It should be in the form
described in the section ‘Matching Control’ in zshcompwid(1).
matcher-list
This style can be set to a list of match specifications that
are to be applied everywhere. Match specifications are
described in the section ‘Matching Control’ in zshcompwid(1).
The completion system will try them one after another for each
completer selected. For example, to try first simple comple-
tion and, if that generates no matches, case-insensitive com-
pletion:
zstyle ’:completion:*’ matcher-list ’’ ’m:{a-zA-Z}={A-Za-z}’
By default each specification replaces the previous one; how-
ever, if a specification is prefixed with +, it is added to the
existing list. Hence it is possible to create increasingly
general specifications without repetition:
zstyle ’:completion:*’ matcher-list ’’ ’+m{a-Z}={A-Z}’ ’+m{A-Z}={a-z}’
It is possible to create match specifications valid for partic-
ular completers by using the third field of the context. For
example, to use the completers _complete and _prefix but only
allow case-insensitive completion with _complete:
zstyle ’:completion:*’ completer _complete _prefix
zstyle ’:completion:*:complete:*’ matcher-list \
’’ ’m:{a-zA-Z}={A-Za-z}’
User-defined names, as explained for the completer style, are
available. This makes it possible to try the same completer
more than once with different match specifications each time.
For example, to try normal completion without a match specifi-
cation, then normal completion with case-insensitive matching,
then correction, and finally partial-word completion:
zstyle ’:completion:*’ completer _complete _correct _complete:foo
zstyle ’:completion:*:complete:*’ matcher-list \
’’ ’m:{a-zA-Z}={A-Za-z}’
zstyle ’:completion:*:foo:*’ matcher-list \
’m:{a-zA-Z}={A-Za-z} r:|[-_./]=* r:|=*’
If the style is unset in any context no match specification is
applied. Note also that some completers such as _correct and
_approximate do not use the match specifications at all, though
these completers will only ever called once even if the
matcher-list contains more than one element.
Where multiple specifications are useful, note that the entire
completion is done for each element of matcher-list, which can
quickly reduce the shell’s performance. As a rough rule of
thumb, one to three strings will give acceptable performance.
On the other hand, putting multiple space-separated values into
the same string does not have an appreciable impact on perfor-
mance.
max-errors
This is used by the _approximate and _correct completer func-
tions to determine the maximum number of errors to allow. The
completer will try to generate completions by first allowing
one error, then two errors, and so on, until either a match or
matches were found or the maximum number of errors given by
this style has been reached.
If the value for this style contains the string ‘numeric’, the
completer function will take any numeric argument as the maxi-
mum number of errors allowed. For example, with
zstyle ’:completion:*:approximate:::’ max-errors 2 numeric
two errors are allowed if no numeric argument is given, but
with a numeric argument of six (as in ‘ESC-6 TAB’), up to six
errors are accepted. Hence with a value of ‘0 numeric’, no
correcting completion will be attempted unless a numeric argu-
ment is given.
If the value contains the string ‘not-numeric’, the completer
will not try to generate corrected completions when given a
numeric argument, so in this case the number given should be
greater than zero. For example, ‘2 not-numeric’ specifies that
correcting completion with two errors will usually be per-
formed, but if a numeric argument is given, correcting comple-
tion will not be performed.
The default value for this style is ‘2 numeric’.
max-matches-width
This style is used to determine the trade off between the width
of the display used for matches and the width used for their
descriptions when the verbose style is in effect. The value
gives the number of display columns to reserve for the matches.
The default is half the width of the screen.
This has the most impact when several matches have the same
description and so will be grouped together. Increasing the
style will allow more matches to be grouped together; decreas-
ing it will allow more of the description to be visible.
menu If this is true in the context of any of the tags defined for
the current completion menu completion will be used. The value
for a specific tag will take precedence over that for the
‘default’ tag.
If none of the values found in this way is true but at least
one is set to ‘auto’, the shell behaves as if the AUTO_MENU
option is set.
If one of the values is explicitly set to false, menu comple-
tion will be explicitly turned off, overriding the MENU_COM-
PLETE option and other settings.
In the form ‘yes=num’, where ‘yes’ may be any of the true val-
ues (‘yes’, ‘true’, ‘on’ and ‘1’), menu completion will be
turned on if there are at least num matches. In the form
‘yes=long’, menu completion will be turned on if the list does
not fit on the screen. This does not activate menu completion
if the widget normally only lists completions, but menu comple-
tion can be activated in that case with the value
‘yes=long-list’ (Typically, the value ‘select=long-list’
described later is more useful as it provides control over
scrolling.)
Similarly, with any of the ‘false’ values (as in ‘no=10’), menu
completion will not be used if there are num or more matches.
The value of this widget also controls menu selection, as
implemented by the zsh/complist module. The following values
may appear either alongside or instead of the values above.
If the value contains the string ‘select’, menu selection will
be started unconditionally.
In the form ‘select=num’, menu selection will only be started
if there are at least num matches. If the values for more than
one tag provide a number, the smallest number is taken.
Menu selection can be turned off explicitly by defining a value
containing the string‘no-select’.
It is also possible to start menu selection only if the list of
matches does not fit on the screen by using the value
‘select=long’. To start menu selection even if the current
widget only performs listing, use the value ‘select=long-list’.
To turn on menu completion or menu selection when a there are a
certain number of matches or the list of matches does not fit
on the screen, both of ‘yes=’ and ‘select=’ may be given twice,
once with a number and once with ‘long’ or ‘long-list’.
Finally, it is possible to activate two special modes of menu
selection. The word ‘interactive’ in the value causes interac-
tive mode to be entered immediately when menu selection is
started; see the description of the zsh/complist module in zsh-
modules(1).RE for a description of interactive mode. Including
the string ‘search’ does the same for incremental search mode.
To select backward incremental search, include the string
‘search-backward’. )
muttrc If set, gives the location of the mutt configuration
file. It defaults to ‘~/.muttrc’.
numbers
This is used with the jobs tag. If it is ‘true’, the
shell will complete job numbers instead of the shortest
unambiguous prefix of the job command text. If the
value is a number, job numbers will only be used if that
many words from the job descriptions are required to
resolve ambiguities. For example, if the value is ‘1’,
strings will only be used if all jobs differ in the
first word on their command lines.
old-list
This is used by the _oldlist completer. If it is set to
‘always’, then standard widgets which perform listing
will retain the current list of matches, however they
were generated; this can be turned off explicitly with
the value ‘never’, giving the behaviour without the
_oldlist completer. If the style is unset, or any other
value, then the existing list of completions is dis-
played if it is not already; otherwise, the standard
completion list is generated; this is the default
behaviour of _oldlist. However, if there is an old list
and this style contains the name of the completer func-
tion that generated the list, then the old list will be
used even if it was generated by a widget which does not
do listing.
For example, suppose you type ^Xc to use the _cor-
rect_word widget, which generates a list of corrections
for the word under the cursor. Usually, typing ^D would
generate a standard list of completions for the word on
the command line, and show that. With _oldlist, it will
instead show the list of corrections already generated.
As another example consider the _match completer: with
the insert-unambiguous style set to ‘true’ it inserts
only a common prefix string, if there is any. However,
this may remove parts of the original pattern, so that
further completion could produce more matches than on
the first attempt. By using the _oldlist completer and
setting this style to _match, the list of matches gener-
ated on the first attempt will be used again.
old-matches
This is used by the _all_matches completer to decide if
an old list of matches should be used if one exists.
This is selected by one of the ‘true’ values or by the
string ‘only’. If the value is ‘only’, _all_matches
will only use an old list and won’t have any effect on
the list of matches currently being generated.
If this style is set it is generally unwise to call the
_all_matches completer unconditionally. One possible
use is for either this style or the completer style to
be defined with the -e option to zstyle to make the
style conditional.
old-menu
This is used by the _oldlist completer. It controls how
menu completion behaves when a completion has already
been inserted and the user types a standard completion
key such as TAB. The default behaviour of _oldlist is
that menu completion always continues with the existing
list of completions. If this style is set to ‘false’,
however, a new completion is started if the old list was
generated by a different completion command; this is the
behaviour without the _oldlist completer.
For example, suppose you type ^Xc to generate a list of
corrections, and menu completion is started in one of
the usual ways. Usually, or with this style set to
false, typing TAB at this point would start trying to
complete the line as it now appears. With _oldlist, it
instead continues to cycle through the list of correc-
tions.
original
This is used by the _approximate and _correct completers
to decide if the original string should be added as a
possible completion. Normally, this is done only if
there are at least two possible corrections, but if this
style is set to ‘true’, it is always added. Note that
the style will be examined with the completer field in
the context name set to correct-num or approximate-num,
where num is the number of errors that were accepted.
packageset
This style is used when completing arguments of the
Debian ‘dpkg’ program. It contains an override for the
default package set for a given context. For example,
zstyle ’:completion:*:complete:dpkg:option--status-1:*’ \
packageset avail
causes available packages, rather than only installed
packages, to be completed for ‘dpkg --status’.
path The function that completes color names uses this style
with the colors tag. The value should be the pathname
of a file containing color names in the format of an X11
rgb.txt file. If the style is not set but this file is
found in one of various standard locations it will be
used as the default.
pine-directory
If set, specifies the directory containing PINE mailbox
files. It defaults to ‘~/mail’.
ports A list of Internet service names (network ports) to com-
plete. If this is not set, service names are taken from
the file ‘/etc/services’.
prefix-hidden
This is used for certain completions which share a com-
mon prefix, for example command options beginning with
dashes. If it is ‘true’, the prefix will not be shown
in the list of matches.
The default value for this style is ‘false’.
prefix-needed
This, too, is used for matches with a common prefix. If
it is set to ‘true’ this common prefix must be typed by
the user to generate the matches. In the case of com-
mand options, this means that the initial ‘-’, ‘+’, or
‘--’ must be typed explicitly before option names will
be completed.
The default value for this style is ‘true’.
preserve-prefix
This style is used when completing path names. Its
value should be a pattern matching an initial prefix of
the word to complete that should be left unchanged under
all circumstances. For example, on some Unices an ini-
tial ‘//’ (double slash) has a special meaning; setting
this style to the string ‘//’ will preserve it. As
another example, setting this style to ‘?:/’ under Cyg-
win would allow completion after ‘a:/...’ and so on.
range This is used by the _history completer and the _his-
tory_complete_word bindable command to decide which
words should be completed.
If it is a singe number, only the last N words from the
history will be completed.
If it is a range of the form ‘max:slice’, the last slice
words will be completed; then if that yields no matches,
the slice words before those will be tried and so on.
This process stops either when at least one match was
been found, or max words have been tried.
The default is to complete all words from the history at
once.
regular
This style is used by the _expand_alias completer and
bindable command. If set to ‘true’ (the default), regu-
lar aliases will be expanded but only in command posi-
tion. If it is set to ‘false’, regular aliases will
never be expanded. If it is set to ‘always’, regular
aliases will be expanded even if not in command posi-
tion.
remote-access
If set to false, certain commands will be prevented from
making Internet connections to retrieve remote informa-
tion. This includes the completion for the CVS command.
It is not always possible to know if connections are in
fact to a remote site, so some may be prevented unneces-
sarily.
remove-all-dups
The _history_complete_word bindable command and the
_history completer use this to decide if all duplicate
matches should be removed, rather than just consecutive
duplicates.
select-prompt
If this is set for the default tag, its value will be
displayed during menu selection (see the menu style
above) when the completion list does not fit on the
screen as a whole. The same escapes as for the
list-prompt style are understood, except that the num-
bers refer to the match or line the mark is on. A
default prompt is used when the value is the empty
string.
select-scroll
This style is tested for the default tag and determines
how a completion list is scrolled during a menu selec-
tion (see the menu style above) when the completion list
does not fit on the screen as a whole. If the value is
‘0’ (zero), the list is scrolled by half-screenfuls; if
it is a positive integer, the list is scrolled by the
given number of lines; if it is a negative number, the
list is scrolled by a screenful minus the absolute value
of the given number of lines. The default is to scroll
by single lines.
separate-sections
This style is used with the manuals tag when completing
names of manual pages. If it is ‘true’, entries for
different sections are added separately using tag names
of the form ‘manual.X’, where X is the section number.
When the group-name style is also in effect, pages from
different sections will appear separately. This style
is also used similarly with the words style when com-
pleting words for the dict command. It allows words from
different dictionary databases to be added separately.
The default for this style is ‘false’.
single-ignored
This is used by the _ignored completer when there is
only one match. If its value is ‘show’, the single
match will be displayed but not inserted. If the value
is ‘menu’, then the single match and the original string
are both added as matches and menu completion is
started, making it easy to select either of them.
sort Many completion widgets call _description at some point
which decides whether the matches are added sorted or
unsorted (often indirectly via _wanted or _requested).
This style can be set explicitly to one of the usual
true or false values as an override. If it is not set
for the context, the standard behaviour of the calling
widget is used.
The style is tested first against the full context
including the tag, and if that fails to produce a value
against the context without the tag.
If the calling widget explicitly requests unsorted
matches, this is usually honoured. However, the default
(unsorted) behaviour of completion for the command his-
tory may be overridden by setting the style to true.
In the _expand completer, if it is set to ‘true’, the
expansions generated will always be sorted. If it is
set to ‘menu’, then the expansions are only sorted when
they are offered as single strings but not in the string
containing all possible expansions.
special-dirs
Normally, the completion code will not produce the
directory names ‘.’ and ‘..’ as possible completions.
If this style is set to ‘true’, it will add both ‘.’ and
‘..’ as possible completions; if it is set to ‘..’, only
‘..’ will be added.
The following example sets special-dirs to ‘..’ when the
current prefix is empty, is a single ‘.’, or consists
only of a path beginning with ‘../’. Otherwise the
value is ‘false’.
zstyle -e ’:completion:*’ special-dirs \
’[[ $PREFIX = (../)#(|.|..) ]] && reply=(..)’
squeeze-slashes
If set to ‘true’, sequences of slashes in filename paths
(for example in ‘foo//bar’) will be treated as a single
slash. This is the usual behaviour of UNIX paths. How-
ever, by default the file completion function behaves as
if there were a ‘*’ between the slashes.
stop If set to ‘true’, the _history_complete_word bindable
command will stop once when reaching the beginning or
end of the history. Invoking _history_complete_word
will then wrap around to the opposite end of the his-
tory. If this style is set to ‘false’ (the default),
_history_complete_word will loop immediately as in a
menu completion.
strip-comments
If set to ‘true’, this style causes non-essential com-
ment text to be removed from completion matches. Cur-
rently it is only used when completing e-mail addresses
where it removes any display name from the addresses,
cutting them down to plain user@host form.
subst-globs-only
This is used by the _expand completer. If it is set to
‘true’, the expansion will only be used if it resulted
from globbing; hence, if expansions resulted from the
use of the substitute style described below, but these
were not further changed by globbing, the expansions
will be rejected.
The default for this style is ‘false’.
substitute
This boolean style controls whether the _expand com-
pleter will first try to expand all substitutions in the
string (such as ‘$(...)’ and ‘${...}’).
The default is ‘true’.
suffix This is used by the _expand completer if the word starts
with a tilde or contains a parameter expansion. If it
is set to ‘true’, the word will only be expanded if it
doesn’t have a suffix, i.e. if it is something like
‘~foo’ or ‘$foo’ rather than ‘~foo/’ or ‘$foo/bar’,
unless that suffix itself contains characters eligible
for expansion. The default for this style is ‘true’.
tag-order
This provides a mechanism for sorting how the tags
available in a particular context will be used.
The values for the style are sets of space-separated
lists of tags. The tags in each value will be tried at
the same time; if no match is found, the next value is
used. (See the file-patterns style for an exception to
this behavior.)
For example:
zstyle ’:completion:*:complete:-command-:*’ tag-order \
’commands functions’
specifies that completion in command position first
offers external commands and shell functions. Remaining
tags will be tried if no completions are found.
In addition to tag names, each string in the value may
take one of the following forms:
- If any value consists of only a hyphen, then
only the tags specified in the other values are
generated. Normally all tags not explicitly
selected are tried last if the specified tags
fail to generate any matches. This means that a
single value consisting only of a single hyphen
turns off completion.
! tags...
A string starting with an exclamation mark spec-
ifies names of tags that are not to be used.
The effect is the same as if all other possible
tags for the context had been listed.
tag:label ...
Here, tag is one of the standard tags and label
is an arbitrary name. Matches are generated as
normal but the name label is used in contexts
instead of tag. This is not useful in words
starting with !.
If the label starts with a hyphen, the tag is
prepended to the label to form the name used for
lookup. This can be used to make the completion
system try a certain tag more than once, supply-
ing different style settings for each attempt;
see below for an example.
tag:label:description
As before, but description will replace the ‘%d’
in the value of the format style instead of the
default description supplied by the completion
function. Spaces in the description must be
quoted with a backslash. A ‘%d’ appearing in
description is replaced with the description
given by the completion function.
In any of the forms above the tag may be a pattern or
several patterns in the form ‘{pat1,pat2...}’. In this
case all matching tags will be used except for any given
explicitly in the same string.
One use of these features is to try one tag more than
once, setting other styles differently on each attempt,
but still to use all the other tags without having to
repeat them all. For example, to make completion of
function names in command position ignore all the com-
pletion functions starting with an underscore the first
time completion is tried:
zstyle ’:completion:*:*:-command-:*’ tag-order \
’functions:-non-comp *’ functions
zstyle ’:completion:*:functions-non-comp’ ignored-patterns ’_*’
On the first attempt, all tags will be offered but the
functions tag will be replaced by functions-non-comp.
The ignored-patterns style is set for this tag to
exclude functions starting with an underscore. If there
are no matches, the second value of the tag-order style
is used which completes functions using the default tag,
this time presumably including all function names.
The matches for one tag can be split into different
groups. For example:
zstyle ’:completion:*’ tag-order \
’options:-long:long\ options
options:-short:short\ options
options:-single-letter:single\ letter\ options’
zstyle ’:completion:*:options-long’ ignored-patterns ’[-+](|-|[^-]*)’
zstyle ’:completion:*:options-short’ ignored-patterns ’--*’ ’[-+]?’
zstyle ’:completion:*:options-single-letter’ ignored-patterns ’???*’
With the group-names style set, options beginning with
‘--’, options beginning with a single ‘-’ or ‘+’ but
containing multiple characters, and single-letter
options will be displayed in separate groups with dif-
ferent descriptions.
Another use of patterns is to try multiple match speci-
fications one after another. The matcher-list style
offers something similar, but it is tested very early in
the completion system and hence can’t be set for single
commands nor for more specific contexts. Here is how to
try normal completion without any match specification
and, if that generates no matches, try again with
case-insensitive matching, restricting the effect to
arguments of the command foo:
zstyle ’:completion:*:*:foo:*’ tag-order ’*’ ’*:-case’
zstyle ’:completion:*-case’ matcher ’m:{a-z}={A-Z}’
First, all the tags offered when completing after foo
are tried using the normal tag name. If that generates
no matches, the second value of tag-order is used, which
tries all tags again except that this time each has
-case appended to its name for lookup of styles. Hence
this time the value for the matcher style from the sec-
ond call to zstyle in the example is used to make com-
pletion case-insensitive.
It is possible to use the -e option of the zstyle
builtin command to specify conditions for the use of
particular tags. For example:
zstyle -e ’*:-command-:*’ tag-order ’
if [[ -n $PREFIX$SUFFIX ]]; then
reply=( )
else
reply=( - )
fi’
Completion in command position will be attempted only if
the string typed so far is not empty. This is tested
using the PREFIX special parameter; see zshcompwid for a
description of parameters which are special inside com-
pletion widgets. Setting reply to an empty array pro-
vides the default behaviour of trying all tags at once;
setting it to an array containing only a hyphen disables
the use of all tags and hence of all completions.
If no tag-order style has been defined for a context,
the strings ‘(|*-)argument-* (|*-)option-* values’ and
‘options’ plus all tags offered by the completion func-
tion will be used to provide a sensible default behavior
that causes arguments (whether normal command arguments
or arguments of options) to be completed before option
names for most commands.
urls This is used together with the the urls tag by functions
completing URLs.
If the value consists of more than one string, or if the
only string does not name a file or directory, the
strings are used as the URLs to complete.
If the value contains only one string which is the name
of a normal file the URLs are taken from that file
(where the URLs may be separated by white space or new-
lines).
Finally, if the only string in the value names a direc-
tory, the directory hierarchy rooted at this directory
gives the completions. The top level directory should
be the file access method, such as ‘http’, ‘ftp’, ‘book-
mark’ and so on. In many cases the next level of direc-
tories will be a filename. The directory hierarchy can
descend as deep as necessary.
For example,
zstyle ’:completion:*’ urls ~/.urls
mkdir -p ~/.urls/ftp/ftp.zsh.org/pub/development
allows completion of all the components of the URL
ftp://ftp.zsh.org/pub/development after suitable com-
mands such as ‘netscape’ or ‘lynx’. Note, however, that
access methods and files are completed separately, so if
the hosts style is set hosts can be completed without
reference to the urls style.
See the description in the function _urls itself for
more information (e.g. ‘more $^fpath/_urls(N)’).
use-cache
If this is set, the completion caching layer is acti-
vated for any completions which use it (via the
_store_cache, _retrieve_cache, and _cache_invalid func-
tions). The directory containing the cache files can be
changed with the cache-path style.
use-compctl
If this style is set to a string not equal to false, 0,
no, and off, the completion system may use any comple-
tion specifications defined with the compctl builtin
command. If the style is unset, this is done only if
the zsh/compctl module is loaded. The string may also
contain the substring ‘first’ to use completions defined
with ‘compctl -T’, and the substring ‘default’ to use
the completion defined with ‘compctl -D’.
Note that this is only intended to smooth the transition
from compctl to the new completion system and may disap-
pear in the future.
Note also that the definitions from compctl will only be
used if there is no specific completion function for the
command in question. For example, if there is a func-
tion _foo to complete arguments to the command foo, com-
pctl will never be invoked for foo. However, the com-
pctl version will be tried if foo only uses default com-
pletion.
use-perl
Various parts of the function system use awk to extract
words from files or command output as this universally
available. However, many versions of awk have arbitrary
limits on the size of input. If this style is set, perl
will be used instead. This is almost always preferable
if perl is available on your system.
Currently this is only used in completions for ‘make’,
but it may be extended depending on authorial frustra-
tion.
users This may be set to a list of usernames to be completed.
If it is not set or the string on the line doesn’t match
any of the strings in this list, all usernames will be
completed.
users-hosts
The values of this style should be of the form
‘user@host’ or ‘user:host’. It is used for commands that
need pairs of user- and hostnames. These commands will
complete usernames from this style (only), and will
restrict subsequent hostname completion to hosts paired
with that user in one of the values of the style.
It is possible to group values for sets of commands
which allow a remote login, such as rlogin and ssh, by
using the my-accounts tag. Similarly, values for sets
of commands which usually refer to the accounts of other
people, such as talk and finger, can be grouped by using
the other-accounts tag. More ambivalent commands may
use the accounts tag.
users-hosts-ports
Like users-hosts but used for commands like telnet and
containing strings of the form ‘user@host:port’.
verbose
If set, as it is by default, the completion listing is
more verbose. In particular many commands show descrip-
tions for options if this style is ‘true’.
word This is used by the _list completer, which prevents the
insertion of completions until a second completion
attempt when the line has not changed. The normal way
of finding out if the line has changed is to compare its
entire contents between the two occasions. If this
style is true, the comparison is instead performed only
on the current word. Hence if completion is performed
on another word with the same contents, completion will
not be delayed.
CONTROL FUNCTIONS
The initialization script compinit redefines all the widgets which
perform completion to call the supplied widget function _main_com-
plete. This function acts as a wrapper calling the so-called ‘com-
pleter’ functions that generate matches. If _main_complete is called
with arguments, these are taken as the names of completer functions to
be called in the order given. If no arguments are given, the set of
functions to try is taken from the completer style. For example, to
use normal completion and correction if that doesn’t generate any
matches:
zstyle ’:completion:*’ completer _complete _correct
after calling compinit. The default value for this style is ‘_complete
_ignored’, i.e. normally only ordinary completion is tried, first with
the effect of the ignored-patterns style and then without it. The
_main_complete function uses the return value of the completer func-
tions to decide if other completers should be called. If the return
value is zero, no other completers are tried and the _main_complete
function returns.
If the first argument to _main_complete is a single hyphen, the argu-
ments will not be taken as names of completers. Instead, the second
argument gives a name to use in the completer field of the context and
the other arguments give a command name and arguments to call to gen-
erate the matches.
The following completer functions are contained in the distribution,
although users may write their own. Note that in contexts the leading
underscore is stripped, for example basic completion is performed in
the context ‘:completion::complete:...’.
_all_matches
This completer can be used to add a string consisting of all
other matches. As it influences later completers it must
appear as the first completer in the list. The list of all
matches is affected by the avoid-completer and old-matches
styles described above.
It may be useful to use the _generic function described below
to bind _all_matches to its own keystroke, for example:
zle -C all-matches complete-word _generic
bindkey ’^Xa’ all-matches
zstyle ’:completion:all-matches:*’ old-matches only
zstyle ’:completion:all-matches::::’ completer _all_matches
_approximate
This is similar to the basic _complete completer but allows the
completions to undergo corrections. The maximum number of
errors can be specified by the max-errors style; see the
description of approximate matching in zshexpn(1) for how
errors are counted. Normally this completer will only be tried
after the normal _complete completer:
zstyle ’:completion:*’ completer _complete _approximate
This will give correcting completion if and only if normal com-
pletion yields no possible completions. When corrected comple-
tions are found, the completer will normally start menu comple-
tion allowing you to cycle through these strings.
This completer uses the tags corrections and original when gen-
erating the possible corrections and the original string. The
format style for the former may contain the additional
sequences ‘%e’ and ‘%o’ which will be replaced by the number of
errors accepted to generate the corrections and the original
string, respectively.
The completer progressively increases the number of errors
allowed up to the limit by the max-errors style, hence if a
completion is found with one error, no completions with two
errors will be shown, and so on. It modifies the completer
name in the context to indicate the number of errors being
tried: on the first try the completer field contains ‘approxi-
mate-1’, on the second try ‘approximate-2’, and so on.
When _approximate is called from another function, the number
of errors to accept may be passed with the -a option. The
argument is in the same format as the max-errors style, all in
one string.
Note that this completer (and the _correct completer mentioned
below) can be quite expensive to call, especially when a large
number of errors are allowed. One way to avoid this is to set
up the completer style using the -e option to zstyle so that
some completers are only used when completion is attempted a
second time on the same string, e.g.:
zstyle -e ’:completion:*’ completer ’
if [[ $_last_try != "$HISTNO$BUFFER$CURSOR" ]]; then
_last_try="$HISTNO$BUFFER$CURSOR"
reply=(_complete _match _prefix)
else
reply=(_ignored _correct _approximate)
fi’
This uses the HISTNO parameter and the BUFFER and CURSOR spe-
cial parameters that are available inside zle and completion
widgets to find out if the command line hasn’t changed since
the last time completion was tried. Only then are the
_ignored, _correct and _approximate completers called.
_complete
This completer generates all possible completions in a con-
text-sensitive manner, i.e. using the settings defined with the
compdef function explained above and the current settings of
all special parameters. This gives the normal completion
behaviour.
To complete arguments of commands, _complete uses the utility
function _normal, which is in turn responsible for finding the
particular function; it is described below. Various contexts
of the form -context- are handled specifically. These are all
mentioned above as possible arguments to the #compdef tag.
Before trying to find a function for a specific context, _com-
plete checks if the parameter ‘compcontext’ is set. Setting
‘compcontext’ allows the usual completion dispatching to be
overridden which is useful in places such as a function that
uses vared for input. If it is set to an array, the elements
are taken to be the possible matches which will be completed
using the tag ‘values’ and the description ‘value’. If it is
set to an associative array, the keys are used as the possible
completions and the values (if non-empty) are used as descrip-
tions for the matches. If ‘compcontext’ is set to a string
containing colons, it should be of the form ‘tag:descr:action’.
In this case the tag and descr give the tag and description to
use and the action indicates what should be completed in one of
the forms accepted by the _arguments utility function described
below.
Finally, if ‘compcontext’ is set to a string without colons,
the value is taken as the name of the context to use and the
function defined for that context will be called. For this
purpose, there is a special context named -command-line- that
completes whole command lines (commands and their arguments).
This is not used by the completion system itself but is
nonetheless handled when explicitly called.
_correct
Generate corrections, but not completions, for the current
word; this is similar to _approximate but will not allow any
number of extra characters at the cursor as that completer
does. The effect is similar to spell-checking. It is based on
_approximate, but the completer field in the context name is
correct.
For example, with:
zstyle ’:completion:::::’ completer _complete _correct _approximate
zstyle ’:completion:*:correct:::’ max-errors 2 not-numeric
zstyle ’:completion:*:approximate:::’ max-errors 3 numeric
correction will accept up to two errors. If a numeric argument
is given, correction will not be performed, but correcting com-
pletion will be, and will accept as many errors as given by the
numeric argument. Without a numeric argument, first correction
and then correcting completion will be tried, with the first
one accepting two errors and the second one accepting three
errors.
When _correct is called as a function, the number of errors to
accept may be given following the -a option. The argument is
in the same form a values to the accept style, all in one
string.
This completer function is intended to be used without the
_approximate completer or, as in the example, just before it.
Using it after the _approximate completer is useless since
_approximate will at least generate the corrected strings gen-
erated by the _correct completer -- and probably more.
_expand
This completer function does not really perform completion, but
instead checks if the word on the command line is eligible for
expansion and, if it is, gives detailed control over how this
expansion is done. For this to happen, the completion system
needs to be invoked with complete-word, not expand-or-complete
(the default binding for TAB), as otherwise the string will be
expanded by the shell’s internal mechanism before the comple-
tion system is started. Note also this completer should be
called before the _complete completer function.
The tags used when generating expansions are all-expansions for
the string containing all possible expansions, expansions when
adding the possible expansions as single matches and original
when adding the original string from the line. The order in
which these strings are generated, if at all, can be controlled
by the group-order and tag-order styles, as usual.
The format string for all-expansions and for expansions may
contain the sequence ‘%o’ which will be replaced by the origi-
nal string from the line.
The kind of expansion to be tried is controlled by the substi-
tute, glob and subst-globs-only styles.
It is also possible to call _expand as a function, in which
case the different modes may be selected with options: -s for
substitute, -g for glob and -o for subst-globs-only.
_expand_alias
If the word the cursor is on is an alias, it is expanded and no
other completers are called. The types of aliases which are to
be expanded can be controlled with the styles regular, global
and disabled.
This function is also a bindable command, see the section
‘Bindable Commands’ below.
_history
Complete words from the shell’s command history. This com-
pleter can be controlled by the remove-all-dups, and sort
styles as for the _history_complete_word bindable command, see
the section ‘Bindable Commands’ below and the section ‘Comple-
tion System Configuration’ above.
_ignored
The ignored-patterns style can be set to a list of patterns
which are compared against possible completions; matching ones
are removed. With this completer those matches can be rein-
stated, as if no ignored-patterns style were set. The com-
pleter actually generates its own list of matches; which com-
pleters are invoked is determined in the same way as for the
_prefix completer. The single-ignored style is also available
as described above.
_list This completer allows the insertion of matches to be delayed
until completion is attempted a second time without the word on
the line being changed. On the first attempt, only the list of
matches will be shown. It is affected by the styles condition
and word, see the section ‘Completion System Configuration’
above.
_match This completer is intended to be used after the _complete com-
pleter. It behaves similarly but the string on the command
line may be a pattern to match against trial completions. This
gives the effect of the GLOB_COMPLETE option.
Normally completion will be performed by taking the pattern
from the line, inserting a ‘*’ at the cursor position and com-
paring the resulting pattern with the possible completions gen-
erated. This can be modified with the match-original style
described above.
The generated matches will be offered in a menu completion
unless the insert-unambiguous style is set to ‘true’; see the
description above for other options for this style.
Note that matcher specifications defined globally or used by
the completion functions (the styles matcher-list and matcher)
will not be used.
_menu This completer was written as simple example function to show
how menu completion can be enabled in shell code. However, it
has the notable effect of disabling menu selection which can be
useful with _generic based widgets. It should be used as the
first completer in the list. Note that this is independent of
the setting of the MENU_COMPLETE option and does not work with
the other menu completion widgets such as reverse-menu-com-
plete, or accept-and-menu-complete.
_oldlist
This completer controls how the standard completion widgets
behave when there is an existing list of completions which may
have been generated by a special completion (i.e. a sepa-
rately-bound completion command). It allows the ordinary com-
pletion keys to continue to use the list of completions thus
generated, instead of producing a new list of ordinary contex-
tual completions. It should appear in the list of completers
before any of the widgets which generate matches. It uses two
styles: old-list and old-menu, see the section ‘Completion Sys-
tem Configuration’ above.
_prefix
This completer can be used to try completion with the suffix
(everything after the cursor) ignored. In other words, the
suffix will not be considered to be part of the word to com-
plete. The effect is similar to the expand-or-complete-prefix
command.
The completer style is used to decide which other completers
are to be called to generate matches. If this style is unset,
the list of completers set for the current context is used --
except, of course, the _prefix completer itself. Furthermore,
if this completer appears more than once in the list of com-
pleters only those completers not already tried by the last
invocation of _prefix will be called.
For example, consider this global completer style:
zstyle ’:completion:*’ completer \
_complete _prefix _correct _prefix:foo
Here, the _prefix completer tries normal completion but ignor-
ing the suffix. If that doesn’t generate any matches, and nei-
ther does the call to the _correct completer after it, _prefix
will be called a second time and, now only trying correction
with the suffix ignored. On the second invocation the com-
pleter part of the context appears as ‘foo’.
To use _prefix as the last resort and try only normal comple-
tion when it is invoked:
zstyle ’:completion:*’ completer _complete ... _prefix
zstyle ’:completion::prefix:*’ completer _complete
The add-space style is also respected. If it is set to ‘true’
then _prefix will insert a space between the matches generated
(if any) and the suffix.
Note that this completer is only useful if the COMPLETE_IN_WORD
option is set; otherwise, the cursor will be moved to the end
of the current word before the completion code is called and
hence there will be no suffix.
bashcompinit
This function provides compatibility with bash’s programmable
completion system. When run it will define the functions,
compgen and complete which correspond to the bash builtins with
the same names. It will then be possible to use completion
specifications and functions written for bash.
BINDABLE COMMANDS
In addition to the context-dependent completions provided, which are
expected to work in an intuitively obvious way, there are a few wid-
gets implementing special behaviour which can be bound separately to
keys. The following is a list of these and their default bindings.
_bash_completions
This function is used by two widgets, _bash_complete-word and
_bash_list-choices. It exists to provide compatibility with
completion bindings in bash. The last character of the binding
determines what is completed: ‘!’, command names; ‘$’, environ-
ment variables; ‘@’, host names; ‘/’, file names; ‘~’ user
names. In bash, the binding preceded by ‘\e’ gives completion,
and preceded by ‘^X’ lists options. As some of these bindings
clash with standard zsh bindings, only ‘\e~’ and ‘^X~’ are
bound by default. To add the rest, the following should be
added to .zshrc after compinit has been run:
for key in ’!’ ’$’ ’@’ ’/’ ’~’; do
bindkey "\e$key" _bash_complete-word
bindkey "^X$key" _bash_list-choices
done
This includes the bindings for ‘~’ in case they were already
bound to something else; the completion code does not override
user bindings.
_correct_filename (^XC)
Correct the filename path at the cursor position. Allows up to
six errors in the name. Can also be called with an argument to
correct a filename path, independently of zle; the correction
is printed on standard output.
_correct_word (^Xc)
Performs correction of the current argument using the usual
contextual completions as possible choices. This stores the
string ‘correct-word’ in the function field of the context name
and then calls the _correct completer.
_expand_alias (^Xa)
This function can be used as a completer and as a bindable com-
mand. It expands the word the cursor is on if it is an alias.
The types of alias expanded can be controlled with the styles
regular, global and disabled.
When used as a bindable command there is one additional feature
that can be selected by setting the complete style to ‘true’.
In this case, if the word is not the name of an alias,
_expand_alias tries to complete the word to a full alias name
without expanding it. It leaves the cursor directly after the
completed word so that invoking _expand_alias once more will
expand the now-complete alias name.
_expand_word (^Xe)
Performs expansion on the current word: equivalent to the
standard expand-word command, but using the _expand completer.
Before calling it, the function field of the context is set to
‘expand-word’.
_generic
This function is not defined as a widget and not bound by
default. However, it can be used to define a widget and will
then store the name of the widget in the function field of the
context and call the completion system. This allows custom
completion widgets with their own set of style settings to be
defined easily. For example, to define a widget that performs
normal completion and starts menu selection:
zle -C foo complete-word _generic
bindkey ’...’ foo
zstyle ’:completion:foo:*’ menu yes select=1
_history_complete_word (\e/)
Complete words from the shell’s command history. This uses the
list, remove-all-dups, sort, and stop styles.
_most_recent_file (^Xm)
Complete the name of the most recently modified file matching
the pattern on the command line (which may be blank). If given
a numeric argument N, complete the Nth most recently modified
file. Note the completion, if any, is always unique.
_next_tags (^Xn)
This command alters the set of matches used to that for the
next tag, or set of tags, either as given by the tag-order
style or as set by default; these matches would otherwise not
be available. Successive invocations of the command cycle
through all possible sets of tags.
_read_comp (^X^R)
Prompt the user for a string, and use that to perform comple-
tion on the current word. There are two possibilities for the
string. First, it can be a set of words beginning ‘_’, for
example ‘_files -/’, in which case the function with any argu-
ments will be called to generate the completions. Unambiguous
parts of the function name will be completed automatically
(normal completion is not available at this point) until a
space is typed.
Second, any other string will be passed as a set of arguments
to compadd and should hence be an expression specifying what
should be completed.
A very restricted set of editing commands is available when
reading the string: ‘DEL’ and ‘^H’ delete the last character;
‘^U’ deletes the line, and ‘^C’ and ‘^G’ abort the function,
while ‘RET’ accepts the completion. Note the string is used
verbatim as a command line, so arguments must be quoted in
accordance with standard shell rules.
Once a string has been read, the next call to _read_comp will
use the existing string instead of reading a new one. To force
a new string to be read, call _read_comp with a numeric argu-
ment.
_complete_debug (^X?)
This widget performs ordinary completion, but captures in a
temporary file a trace of the shell commands executed by the
completion system. Each completion attempt gets its own file.
A command to view each of these files is pushed onto the editor
buffer stack.
_complete_help (^Xh)
This widget displays information about the context names, the
tags, and the completion functions used when completing at the
current cursor position. If given a numeric argument other than
1 (as in ‘ESC-2 ^Xh’), then the styles used and the contexts
for which they are used will be shown, too.
Note that the information about styles may be incomplete; it
depends on the information available from the completion func-
tions called, which in turn is determined by the user’s own
styles and other settings.
_complete_tag (^Xt)
This widget completes symbol tags created by the etags or ctags
programmes (note there is no connection with the completion
system’s tags) stored in a file TAGS, in the format used by
etags, or tags, in the format created by ctags. It will look
back up the path hierarchy for the first occurrence of either
file; if both exist, the file TAGS is preferred. You can spec-
ify the full path to a TAGS or tags file by setting the parame-
ter $TAGSFILE or $tagsfile respectively. The corresponding
completion tags used are etags and vtags, after emacs and vi
respectively.
UTILITY FUNCTIONS
Descriptions follow for utility functions that may be useful when
writing completion functions. If functions are installed in subdirec-
tories, most of these reside in the Base subdirectory. Like the exam-
ple functions for commands in the distribution, the utility functions
generating matches all follow the convention of returning zero if they
generated completions and non-zero if no matching completions could be
added.
Two more features are offered by the _main_complete function. The
arrays compprefuncs and comppostfuncs may contain names of functions
that are to be called immediately before or after completion has been
tried. A function will only be called once unless it explicitly rein-
serts itself into the array.
_all_labels [ -x ] [ -12VJ ] tag name descr [ command args ... ]
This is a convenient interface to the _next_label function
below, implementing the loop shown in the _next_label example.
The command and its arguments are called to generate the
matches. The options stored in the parameter name will auto-
matically be inserted into the args passed to the command.
Normally, they are put directly after the command, but if one
of the args is a single hyphen, they are inserted directly
before that. If the hyphen is the last argument, it will be
removed from the argument list before the command is called.
This allows _all_labels to be used in almost all cases where
the matches can be generated by a single call to the compadd
builtin command or by a call to one of the utility functions.
For example:
local expl
...
if _requested foo; then
...
_all_labels foo expl ’...’ compadd ... - $matches
fi
Will complete the strings from the matches parameter, using
compadd with additional options which will take precedence over
those generated by _all_labels.
_alternative [ -C name ] spec ...
This function is useful in simple cases where multiple tags are
available. Essentially it implements a loop like the one
described for the _tags function below.
The tags to use and the action to perform if a tag is requested
are described using the specs which are of the form:
‘tag:descr:action’. The tags are offered using _tags and if
the tag is requested, the action is executed with the given
description descr. The actions are those accepted by the
_arguments function (described below), excluding the ‘->state’
and ‘=...’ forms.
For example, the action may be a simple function call:
_alternative \
’users:user:_users’ \
’hosts:host:_hosts’
offers usernames and hostnames as possible matches, generated
by the _users and _hosts functions respectively.
Like _arguments, this functions uses _all_labels to execute the
actions, which will loop over all sets of tags. Special han-
dling is only required if there is an additional valid tag, for
example inside a function called from _alternative.
Like _tags this function supports the -C option to give a dif-
ferent name for the argument context field.
_arguments [ -swWACRS ] [ -O name ] [ -M matchspec ] [ : ] spec ...
This function can be used to give a complete specification for
completion for a command whose arguments follow standard UNIX
option and argument conventions. The following forms specify
individual sets of options and arguments; to avoid ambiguity,
these may be separated from the options to _arguments itself by
a single colon.
n:message:action
n::message:action
This describes the n’th normal argument. The message
will be printed above the matches generated and the
action indicates what can be completed in this position
(see below). If there are two colons before the message
the argument is optional. If the message contains only
white space, nothing will be printed above the matches
unless the action adds an explanation string itself.
:message:action
::message:action
Similar, but describes the next argument, whatever num-
ber that happens to be. If all arguments are specified
in this form in the correct order the numbers are unnec-
essary.
*:message:action
*::message:action
*:::message:action
This describes how arguments (usually non-option argu-
ments, those not beginning with - or +) are to be com-
pleted when neither of the first two forms was provided.
Any number of arguments can be completed in this fash-
ion.
With two colons before the message, the words special
array and the CURRENT special parameter are modified to
refer only to the normal arguments when the action is
executed or evaluated. With three colons before the
message they are modified to refer only to the normal
arguments covered by this description.
optspec
optspec:...
This describes an option. The colon indicates handling
for one or more arguments to the option; if it is not
present, the option is assumed to take no arguments.
By default, options are multi-character name, one
‘-word’ per option. With -s, options may be single
characters, with more than one option per word, although
words starting with two hyphens, such as ‘--prefix’, are
still considered complete option names. This is suit-
able for standard GNU options.
The combination of -s with -w allows single-letter
options to be combined in a single word even if one or
more of the options take arguments. For example, if -a
takes an argument, with no -s ‘-ab’ is considered as a
single (unhandled) option; with -s -ab is an option with
the argument ‘b’; with both -s and -w, -ab may be the
option -a and the option(-b) with arguments still to
come.
The option -W takes this a stage further: it is possi-
ble to complete single-letter options even after an
argument that occurs in the same word. However, it
depends on the action performed whether options will
really be completed at this point. For more control,
use a utility function like _guard as part of the
action.
The following forms are available for the initial opt-
spec, whether or not the option has arguments.
*optspec
Here optspec is one of the remaining forms
below. This indicates the following optspec may
be repeated. Otherwise if the corresponding
option is already present on the command line to
the left of the cursor it will not be offered
again.
-optname
+optname
In the simplest form the optspec is just the
option name beginning with a minus or a plus
sign, such as ‘-foo’. The first argument for
the option (if any) must follow as a separate
word directly after the option.
Either of ‘-+optname’ and ‘+-optname’ can be
used to specify that -optname and +optname are
both valid.
In all the remaining forms, the leading ‘-’ may
be replaced by or paired with ‘+’ in this way.
-optname-
The first argument of the option must come
directly after the option name in the same word.
For example, ‘-foo-:...’ specifies that the com-
pleted option and argument will look like
‘-fooarg’.
-optname+
The first argument may appear immediately after
optname in the same word, or may appear as a
separate word after the option. For example,
‘-foo+:...’ specifies that the completed option
and argument will look like either ‘-fooarg’ or
‘-foo arg’.
-optname=
The argument may appear as the next word, or in
same word as the option name provided that it is
separated from it by an equals sign, for example
‘-foo=arg’ or ‘-foo arg’.
-optname=-
The argument to the option must appear after an
equals sign in the same word, and may not be
given in the next argument.
optspec[explanation]
An explanation string may be appended to any of
the preceding forms of optspec by enclosing it
in brackets, as in ‘-q[query operation]’.
The verbose style is used to decide whether the
explanation strings are displayed with the
option in a completion listing.
If no bracketed explanation string is given but
the auto-description style is set and only one
argument is described for this optspec, the
value of the style is displayed, with any
appearance of the sequence ‘%d’ in it replaced
by the message of the first optarg that follows
the optspec; see below.
It is possible for options with a literal ‘+’ or ‘=’ to appear,
but that character must be quoted, for example ‘-\+’.
Each optarg following an optspec must take one of the following
forms:
:message:action
::message:action
An argument to the option; message and action are
treated as for ordinary arguments. In the first form,
the argument is mandatory, and in the second form it is
optional.
This group may be repeated for options which take multi-
ple arguments. In other words, :message1:action1:mes-
sage2:action2 specifies that the option takes two argu-
ments.
:*pattern:message:action
:*pattern::message:action
:*pattern:::message:action
This describes multiple arguments. Only the last optarg
for an option taking multiple arguments may be given in
this form. If the pattern is empty (i.e., :*:), all the
remaining words on the line are to be completed as
described by the action; otherwise, all the words up to
a word matching the pattern are to be completed using
the action.
Multiple colons are treated as for the ‘*:...’ forms for
ordinary arguments: when the message is preceded by two
colons, the words special array and the CURRENT special
parameter are modified during the execution or evalua-
tion of the action to refer only to the words after the
option. When preceded by three colons, they are modi-
fied to refer only to the words covered by this descrip-
tion.
Any literal colon in an optname, message, or action must be preceded
by a backslash, ‘\:’.
Each of the forms above may be preceded by a list in parentheses of
option names and argument numbers. If the given option is on the com-
mand line, the options and arguments indicated in parentheses will not
be offered. For example, ‘(-two -three 1)-one:...’ completes the
option ‘-one’; if this appears on the command line, the options -two
and -three and the first ordinary argument will not be completed after
it. ‘(-foo):...’ specifies an ordinary argument completion; -foo will
not be completed if that argument is already present.
Other items may appear in the list of excluded options to indicate
various other items that should not be applied when the current speci-
fication is matched: a single star (*) for the rest arguments (i.e. a
specification of the form ‘*:...’); a colon (:) for all normal
(non-option-) arguments; and a hyphen (-) for all options. For exam-
ple, if ‘(*)’ appears before an option and the option appears on the
command line, the list of remaining arguments (those shown in the
above table beginning with ‘*:’) will not be completed.
To aid in reuse of specifications, it is possible to precede any of
the forms above with ‘!’; then the form will no longer be completed,
although if the option or argument appears on the command line they
will be skipped as normal. The main use for this is when the argu-
ments are given by an array, and _arguments is called repeatedly for
more specific contexts: on the first call ‘_arguments $global_options’
is used, and on subsequent calls ‘_arguments !$^global_options’.
In each of the forms above the action determines how completions
should be generated. Except for the ‘->string’ form below, the action
will be executed by calling the _all_labels function to process all
tag labels. No special handling of tags is needed unless a function
call introduces a new one.
The forms for action are as follows.
(single unquoted space)
This is useful where an argument is required but it is not pos-
sible or desirable to generate matches for it. The message
will be displayed but no completions listed. Note that even in
this case the colon at the end of the message is needed; it may
only be omitted when neither a message nor an action is given.
(item1 item2 ...)
One of a list of possible matches, for example:
:foo:(foo bar baz)
((item1\:desc1 ...))
Similar to the above, but with descriptions for each possible
match. Note the backslash before the colon. For example,
:foo:((a\:bar b\:baz))
The matches will be listed together with their descriptions if
the description style is set with the values tag in the con-
text.
->string
In this form, _arguments processes the arguments and options
and then returns control to the calling function with parame-
ters set to indicate the state of processing; the calling func-
tion then makes its own arrangements for generating comple-
tions. For example, functions that implement a state machine
can use this type of action.
Where _arguments encounters a ‘->string’, it will strip all
leading and trailing whitespace from string and set the array
state to the set of all stringss for which an action is to be
performed.
By default and in common with all other well behaved completion
functions, _arguments returns zero if it was able to add
matches and non-zero otherwise. However, if the -R option is
given, _arguments will instead return a status of 300 to indi-
cate that $state is to be handled.
In addition to $state, _arguments also sets the global parame-
ters ‘context’, ‘line’ and ‘opt_args’ as described below, and
does not reset any changes made to the special parameters such
as PREFIX and words. This gives the calling function the
choice of resetting these parameters or propagating changes in
them.
A function calling _arguments with at least one action contain-
ing a ‘->string’ therefore must declare appropriate local
parameters:
local context state line
typeset -A opt_args
to avoid _arguments from altering the global environment.
{eval-string}
A string in braces is evaluated as shell code to generate
matches. If the eval-string itself does not begin with an
opening parenthesis or brace it is split into separate words
before execution.
= action
If the action starts with ‘= ’ (an equals sign followed by a
space), _arguments will insert the contents of the argument
field of the current context as the new first element in the
words special array and increment the value of the CURRENT spe-
cial parameter. This has the effect of inserting a dummy word
onto the completion command line while not changing the point
at which completion is taking place.
This is most useful with one of the specifiers that restrict
the words on the command line on which the action is to operate
(the two- and three-colon forms above). One particular use is
when an action itself causes _arguments on a restricted range;
it is necessary to use this trick to insert an appropriate com-
mand name into the range for the second call to _arguments to
be able to parse the line.
word...
word...
This covers all forms other than those above. If the action
starts with a space, the remaining list of words will be
invoked unchanged.
Otherwise it will be invoked with some extra strings placed
after the first word; these are to be passed down as options to
the compadd builtin. They ensure that the state specified by
_arguments, in particular the descriptions of options and argu-
ments, is correctly passed to the completion command. These
additional arguments are taken from the array parameter ‘expl’;
this will be set up before executing the action and hence may
be referred to inside it, typically in an expansion of the form
‘$expl[@]’ which preserves empty elements of the array.
During the performance of the action the array ‘line’ will be set to
the command name and normal arguments from the command line, i.e. the
words from the command line excluding all options and their arguments.
Options are stored in the associative array ‘opt_args’ with option
names as keys and their arguments as the values. For options that
have more than one argument these are given as one string, separated
by colons. All colons in the original arguments are preceded with
backslashes.
The parameter ‘context’ is set when returning to the calling function
to perform an action of the form ‘->string’. It is set to an array of
elements corresponding to the elements of $state. Each element is a
suitable name for the argument field of the context: either a string
of the form ‘option-opt-n’ for the n’th argument of the option -opt,
or a string of the form ‘argument-n’ for the n’th argument. For
‘rest’ arguments, that is those in the list at the end not handled by
position, n is the string ‘rest’. For example, when completing the
argument of the -o option, the name is ‘option-o-1’, while for the
second normal (non-option-) argument it is ‘argument-2’.
Furthermore, during the evaluation of the action the context name in
the curcontext parameter is altered to append the same string that is
stored in the context parameter.
It is possible to specify multiple sets of options and arguments with
the sets separated by single hyphens. The specifications before the
first hyphen (if any) are shared by all the remaining sets. The first
word in every other set provides a name for the set which may appear
in exclusion lists in specifications, either alone or before one of
the possible values described above. In the second case a ‘-’ should
appear between this name and the remainder.
For example:
_arguments \
-a \
- set1 \
-c \
- set2 \
-d \
’:arg:(x2 y2)’
This defines two sets. When the command line contains the option
‘-c’, the ‘-d’ option and the argument will not be considered possible
completions. When it contains ‘-d’ or an argument, the option ‘-c’
will not be considered. However, after ‘-a’ both sets will still be
considered valid.
If the name given for one of the mutually exclusive sets is of the
form ‘(name)’ then only one value from each set will ever be com-
pleted; more formally, all specifications are mutually exclusive to
all other specifications in the same set. This is useful for defining
multiple sets of options which are mutually exclusive and in which the
options are aliases for each other. For example:
_arguments \
-a -b \
- ’(compress)’ \
{-c,--compress}’[compress]’ \
- ’(uncompress)’ \
{-d,--decompress}’[decompress]’
As the completion code has to parse the command line separately for
each set this form of argument is slow and should only be used when
necessary. A useful alternative is often an option specification with
rest-arguments (as in ‘-foo:*:...’); here the option -foo swallows up
all remaining arguments as described by the optarg definitions.
The options -S and -A are available to simplify the specifications for
commands with standard option parsing. With -S, no option will be
completed after a ‘--’ appearing on its own on the line; this argument
will otherwise be ignored; hence in the line
foobar -a -- -b
the ‘-a’ is considered an option but the ‘-b’ is considered an argu-
ment, while the ‘--’ is considered to be neither.
With -A, no options will be completed after the first non-option argu-
ment on the line. The -A must be followed by a pattern matching all
strings which are not to be taken as arguments. For example, to make
_arguments stop completing options after the first normal argument,
but ignoring all strings starting with a hyphen even if they are not
described by one of the optspecs, the form is ‘-A "-*"’.
The option ‘-O name’ specifies the name of an array whose elements
will be passed as arguments to functions called to execute actions.
For example, this can be used to pass the same set of options for the
compadd builtin to all actions.
The option ‘-M spec’ sets a match specification to use to completion
option names and values. It must appear before the first argument
specification. The default is ‘r:|[_-]=* r:|=*’: this allows partial
word completion after ‘_’ and ‘-’, for example ‘-f-b’ can be completed
to ‘-foo-bar’.
The option -C tells _arguments to modify the curcontext parameter for
an action of the form ‘->state’. This is the standard parameter used
to keep track of the current context. Here it (and not the context
array) should be made local to the calling function to avoid passing
back the modified value and should be initialised to the current value
at the start of the function:
local curcontext="$curcontext"
This is useful where it is not possible for multiple states to be
valid together.
The option ‘--’ allows _arguments to work out the names of long
options that support the ‘--help’ option which is standard in many GNU
commands. The command word is called with the argument ‘--help’ and
the output examined for option names. Clearly, it can be dangerous to
pass this to commands which may not support this option as the
behaviour of the command is unspecified.
In addition to options, ‘_arguments --’ will try to deduce the types
of arguments available for options when the form ‘--opt=val’ is valid.
It is also possible to provide hints by examining the help text of the
command and adding specifiers of the form ‘pattern:message:action’;
note that normal _arguments specifiers are not used. The pattern is
matched against the help text for an option, and if it matches the
message and action are used as for other argument specifiers. For
example:
_arguments -- ’*\*:toggle:(yes no)’ \
’*=FILE*:file:_files’ \
’*=DIR*:directory:_files -/’ \
’*=PATH*:directory:_files -/’
Here, ‘yes’ and ‘no’ will be completed as the argument of options
whose description ends in a star; file names will be completed for
options that contain the substring ‘=FILE’ in the description; and
directories will be completed for options whose description contains
‘=DIR’ or ‘=PATH’. The last three are in fact the default and so need
not be given explicitly, although it is possible to override the use
of these patterns. A typical help text which uses this feature is:
-C, --directory=DIR change to directory DIR
so that the above specifications will cause directories to be com-
pleted after ‘--directory’, though not after ‘-C’.
Note also that _arguments tries to find out automatically if the argu-
ment for an option is optional. This can be specified explicitly by
doubling the colon before the message.
If the pattern ends in ‘(-)’, this will removed from the pattern and
the action will be used only directly after the ‘=’, not in the next
word. This is the behaviour of a normal specification defined with
the form ‘=-’.
The ‘_arguments --’ can be followed by the option ‘-i patterns’ to
give patterns for options which are not to be completed. The patterns
can be given as the name of an array parameter or as a literal list in
parentheses. For example,
_arguments -- -i \
"(--(en|dis)able-FEATURE*)"
will cause completion to ignore the options ‘--enable-FEATURE’ and
‘--disable-FEATURE’ (this example is useful with GNU configure).
The ‘_arguments --’ form can also be followed by the option ‘-s pair’
to describe option aliases. Each pair consists of a pattern and a
replacement. For example, some configure-scripts describe options
only as ‘--enable-foo’, but also accept ‘--disable-foo’. To allow
completion of the second form:
_arguments -- -s "(#--enable- --disable-)"
Here is a more general example of the use of _arguments:
_arguments ’-l+:left border:’ \
’-format:paper size:(letter A4)’ \
’*-copy:output file:_files::resolution:(300 600)’ \
’:postscript file:_files -g \*.\(ps\|eps\)’ \
’*:page number:’
This describes three options: ‘-l’, ‘-format’, and ‘-copy’. The first
takes one argument described as ‘left border’ for which no completion
will be offered because of the empty action. Its argument may come
directly after the ‘-l’ or it may be given as the next word on the
line.
The ‘-format’ option takes one argument in the next word, described as
‘paper size’ for which only the strings ‘letter’ and ‘A4’ will be com-
pleted.
The ‘-copy’ option may appear more than once on the command line and
takes two arguments. The first is mandatory and will be completed as
a filename. The second is optional (because of the second colon
before the description ‘resolution’) and will be completed from the
strings ‘300’ and ‘600’.
The last two descriptions say what should be completed as arguments.
The first describes the first argument as a ‘postscript file’ and
makes files ending in ‘ps’ or ‘eps’ be completed. The last descrip-
tion gives all other arguments the description ‘page numbers’ but does
not offer completions.
_cache_invalid cache_identifier
This function returns status zero if the completions cache cor-
responding to the given cache identifier needs rebuilding. It
determines this by looking up the cache-policy style for the
current context. This should provide a function name which is
run with the full path to the relevant cache file as the only
argument.
Example:
_example_caching_policy () {
# rebuild if cache is more than a week old
oldp=( "$1"(Nmw+1) )
(( $#oldp ))
}
_call_function return name [ args ... ]
If a function name exists, it is called with the arguments
args. The return argument gives the name of a parameter in
which the return status from the function name; if return is
empty or a single hyphen it is ignored.
The return value of _call_function itself is zero if the func-
tion name exists and was called and non-zero otherwise.
_call_program tag string ...
This function provides a mechanism for the user to override the
use of an external command. It looks up the command style with
the supplied tag. If the style is set, its value is used as
the command to execute. The strings from the call to
_call_program, or from the style if set, are concatenated with
spaces between them and the resulting string is evaluated. The
return value is the return value of the command called.
_combination [ -s pattern ] tag style spec ... field opts ...
This function is used to complete combinations of values, for
example pairs of hostnames and usernames. The style argument
gives the style which defines the pairs; it is looked up in a
context with the tag specified.
The style name consists of field names separated by hyphens,
for example ‘users-hosts-ports’. For each field for a value is
already known, a spec of the form ‘field=pattern’ is given.
For example, if the command line so far specifies a user ‘pws’,
the argument ‘users=pws’ should appear.
The next argument with no equals sign is taken as the name of
the field for which completions should be generated (presumably
not one of the fields for which the value is known).
The matches generated will be taken from the value of the
style. These should contain the possible values for the combi-
nations in the appropriate order (users, hosts, ports in the
example above). The different fields the values for the dif-
ferent fields are separated by colons. This can be altered
with the option -s to _combination which specifies a pattern.
Typically this is a character class, as for example ‘-s "[:@]"’
in the case of the users-hosts style. Each ‘field=pattern’
specification restricts the completions which apply to elements
of the style with appropriately matching fields.
If no style with the given name is defined for the given tag,
or if none of the strings in style’s value match, but a func-
tion name of the required field preceded by an underscore is
defined, that function will be called to generate the matches.
For example, if there is no ‘users-hosts-ports’ or no matching
hostname when a host is required, the function ‘_hosts’ will
automatically be called.
If the same name is used for more than one field, in both the
‘field=pattern’ and the argument that gives the name of the
field to be completed, the number of the field (starting with
one) may be given after the fieldname, separated from it by a
colon.
All arguments after the required field name are passed to com-
padd when generating matches from the style value, or to the
functions for the fields if they are called.
_describe [ -oO | -t tag ] descr name1 [ name2 ] opts ... -- ...
This function associates completions with descriptions. Multi-
ple groups separated by -- can be supplied, potentially with
different completion options opts.
The descr is taken as a string to display above the matches if
the format style for the descriptions tag is set. This is fol-
lowed by one or two names of arrays followed by options to pass
to compadd. The first array contains the possible completions
with their descriptions in the form ‘completion:description’.
If a second array is given, it should have the same number of
elements as the first; in this case the corresponding elements
are added as possible completions instead of the completion
strings from the first array. The completion list will retain
the descriptions from the first array. Finally, a set of com-
pletion options can appear.
If the option ‘-o’ appears before the first argument, the
matches added will be treated as names of command options (N.B.
not shell options), typically following a ‘-’, ‘--’ or ‘+’ on
the command line. In this case _describe uses the prefix-hid-
den, prefix-needed and verbose styles to find out if the
strings should be added as completions and if the descriptions
should be shown. Without the ‘-o’ option, only the verbose
style is used to decide how descriptions are shown. If ‘-O’ is
used instead of ‘-O’, command options are completed as above
but _describe will not handle the prefix-needed style.
With the -t option a tag can be specified. The default is
‘values’ or, if the -o option is given, ‘options’.
If selected by the list-grouped style, strings with the same
description will appear together in the list.
_describe uses the _all_labels function to generate the
matches, so it does not need to appear inside a loop over tag
labels.
_description [ -x ] [ -12VJ ] tag name descr [ spec ... ]
This function is not to be confused with the previous one; it
is used as a helper function for creating options to compadd.
It is buried inside many of the higher level completion func-
tions and so often does not need to be called directly.
The styles listed below are tested in the current context using
the given tag. The resulting options for compadd are put into
the array named name (this is traditionally ‘expl’, but this
convention is not enforced). The description for the corre-
sponding set of matches is passed to the function in descr.
The styles tested are: format, hidden, matcher, ignored-pat-
terns and group-name. The format style is first tested for the
given tag and then for the descriptions tag if no value was
found, while the remainder are only tested for the tag given as
the first argument. The function also calls _setup which tests
some more styles.
The string returned by the format style (if any) will be modi-
fied so that the sequence ‘%d’ is replaced by the descr given
as the third argument without any leading or trailing white
space. If, after removing the white space, the descr is the
empty string, the format style will not be used and the options
put into the name array will not contain an explanation string
to be displayed above the matches.
If _description is called with more than three arguments, the
additional specs should be of the form ‘char:str’. These sup-
ply escape sequence replacements for the format style: every
appearance of ‘%char’ will be replaced by string.
If the -x option is given, the description will be passed to
compadd using the -x option instead of the default -X. This
means that the description will be displayed even if there are
no corresponding matches.
The options placed in the array name take account of the
group-name style, so matches are placed in a separate group
where necessary. The group normally has its elements sorted
(by passing the option -J to compadd), but if an option start-
ing with ‘-V’, ‘-J’, ‘-1’, or ‘-2’ is passed to _description,
that option will be included in the array. Hence it is possi-
ble for the completion group to be unsorted by giving the
option ‘-V’, ‘-1V’, or ‘-2V’.
In most cases, the function will be used like this:
local expl
_description files expl file
compadd "$expl[@]" - "$files[@]"
Note the use of the parameter expl, the hyphen, and the list of
matches. Almost all calls to compadd within the completion
system use a similar format; this ensures that user-specified
styles are correctly passed down to the builtins which imple-
ment the internals of completion.
_dispatch context string ...
This sets the current context to context and looks for comple-
tion functions to handle this context by hunting through the
list of command names or special contexts (as described above
for compdef) given as string .... The first completion func-
tion to be defined for one of the contexts in the list is used
to generate matches. Typically, the last string is -default-
to cause the function for default completion to be used as a
fallback.
The function sets the parameter $service to the string being
tried, and sets the context/command field (the fourth) of the
$curcontext parameter to the context given as the first argu-
ment.
_files The function _files calls _path_files with all the arguments it
was passed except for -g and -/. The use of these two options
depends on the setting of the file-patterns style.
This function accepts the full set of options allowed by
_path_files, described below.
_gnu_generic
This function is a simple wrapper around the _arguments func-
tion described above. It can be used to determine automati-
cally the long options understood by commands that produce a
list when passed the option ‘--help’. It is intended to be
used as a top-level completion function in its own right. For
example, to enable option completion for the commands foo and
bar, use
compdef _gnu_generic foo bar
after the call to compinit.
The completion system as supplied is conservative in its use of
this function, since it is important to be sure the command
understands the option ‘-’-help’.
_guard [ options ] pattern descr
This function is intended to be used in the action for the
specifications passed to _arguments and similar functions. It
returns immediately with a non-zero return value if the string
to be completed does not match the pattern. If the pattern
matches, the descr is displayed; the function then returns zero
if the word to complete is not empty, non-zero otherwise.
The pattern may be preceded by any of the options understood by
compadd that are passed down from _description, namely -M, -J,
-V, -1, -2, -n, -F and -X. All of these options will be
ignored. This fits in conveniently with the argument-passing
conventions of actions for _arguments.
As an example, consider a command taking the options -n and
-none, where -n must be followed by a numeric value in the same
word. By using:
_arguments ’-n-: :_guard "[0-9]#" "numeric value"’ ’-none’
_arguments can be made to both display the message ‘numeric
value’ and complete options after ‘-n<TAB>’. If the ‘-n’ is
already followed by one or more digits (the pattern passed to
_guard) only the message will be displayed; if the ‘-n’ is fol-
lowed by another character, only options are completed.
_message [ -r12 ] [ -VJ group ] descr
_message -e [ tag ] descr
The descr is used in the same way as the third argument to the
_description function, except that the resulting string will
always be shown whether or not matches were generated. This is
useful for displaying a help message in places where no comple-
tions can be generated.
The format style is examined with the messages tag to find a
message; the usual tag, descriptions, is used only if the style
is not set with the former.
If the -r option is given, no style is used; the descr is taken
literally as the string to display. This is most useful when
the descr comes from a pre-processed argument list which
already contains an expanded description.
The -12VJ options and the group are passed to compadd and hence
determine the group the message string is added to.
The second form gives a description for completions with the
tag tag to be shown even if there are no matches for that tag.
The tag can be omitted and if so the tag is taken from the
parameter $curtag; this is maintained by the completion system
and so is usually correct.
_multi_parts sep array
The argument sep is a separator character. The array may be
either the name of an array parameter or a literal array in the
form ‘(foo bar)’, a parenthesised list of words separated by
whitespace. The possible completions are the strings from the
array. However, each chunk delimited by sep will be completed
separately. For example, the _tar function uses ‘_multi_parts
/ patharray’ to complete partial file paths from the given
array of complete file paths.
The -i option causes _multi_parts to insert a unique match even
if that requires multiple separators to be inserted. This is
not usually the expected behaviour with filenames, but certain
other types of completion, for example those with a fixed set
of possibilities, may be more suited to this form.
Like other utility functions, this function accepts the ‘-V’,
‘-J’, ‘-1’, ‘-2’, ‘-n’, ‘-f’, ‘-X’, ‘-M’, ‘-P’, ‘-S’, ‘-r’,
‘-R’, and ‘-q’ options and passes them to the compadd builtin.
_next_label [ -x ] [ -12VJ ] tag name descr [ options ... ]
This function is used to implement the loop over different tag
labels for a particular tag as described above for the
tag-order style. On each call it checks to see if there are
any more tag labels; if there is it returns status zero,
otherwise non-zero. As this function requires a current tag to
be set, it must always follow a call to _tags or _requested.
The -x12VJ options and the first three arguments are passed to
the _description function. Where appropriate the tag will be
replaced by a tag label in this call. Any description given in
the tag-order style is preferred to the descr passed to
_next_label.
The options given after the descr are set in the parameter
given by name, and hence are to be passed to compadd or what-
ever function is called to add the matches.
Here is a typical use of this function for the tag foo. The
call to _requested determines if tag foo is required at all;
the loop over _next_label handles any labels defined for the
tag in the tag-order style.
local expl ret=1
...
if _requested foo; then
...
while _next_label foo expl ’...’; do
compadd "$expl[@]" ... && ret=0
done
...
fi
return ret
_normal
This is the standard function called to handle completion out-
side any special -context-. It is called both to complete the
command word and also the arguments for a command. In the sec-
ond case, _normal looks for a special completion for that com-
mand, and if there is none it uses the completion for the
-default- context.
A second use is to reexamine the command line specified by the
$words array and the $CURRENT parameter after those have been
modified. For example, the function _precommand, which com-
pletes after pre-command specifiers such as nohup, removes the
first word from the words array, decrements the CURRENT parame-
ter, then calls _normal again. The effect is that ‘nohup cmd
...’ is treated in the same way as ‘cmd ...’.
If the command name matches one of the patterns given by one of
the options -p or -P to compdef, the corresponding completion
function is called and then the parameter _compskip is checked.
If it is set completion is terminated at that point even if no
matches have been found. This is the same effect as in the
-first- context.
_options
This can be used to complete the names of shell options. It
provides a matcher specification that ignores a leading ‘no’,
ignores underscores and allows upper-case letters to match
their lower-case counterparts (for example, ‘glob’, ‘noglob’,
‘NO_GLOB’ are all completed). Any arguments are propagated to
the compadd builtin.
_options_set and _options_unset
These functions complete only set or unset options, with the
same matching specification used in the _options function.
Note that you need to uncomment a few lines in the _main_com-
plete function for these functions to work properly. The lines
in question are used to store the option settings in effect
before the completion widget locally sets the options it needs.
Hence these functions are not generally used by the completion
system.
_parameters
This is used to complete the names of shell parameters.
The option ‘-g pattern’ limits the completion to parameters
whose type matches the pattern. The type of a parameter is
that shown by ‘print ${(t)param}’, hence judicious use of ‘*’
in pattern is probably necessary.
All other arguments are passed to the compadd builtin.
_path_files
This function is used throughout the completion system to com-
plete filenames. It allows completion of partial paths. For
example, the string ‘/u/i/s/sig’ may be completed to
‘/usr/include/sys/signal.h’.
The options accepted by both _path_files and _files are:
-f Complete all filenames. This is the default.
-/ Specifies that only directories should be completed.
-g pattern
Specifies that only files matching the pattern should be
completed.
-W paths
Specifies path prefixes that are to be prepended to the
string from the command line to generate the filenames
but that should not be inserted as completions nor shown
in completion listings. Here, paths may be the name of
an array parameter, a literal list of paths enclosed in
parentheses or an absolute pathname.
-F ignored-files
This behaves as for the corresponding option to the com-
padd builtin. It gives direct control over which file-
names should be ignored. If the option is not present,
the ignored-patterns style is used.
Both _path_files and _files also accept the following options
which are passed to compadd: ‘-J’, ‘-V’, ‘-1’, ‘-2’, ‘-n’,
‘-X’, ‘-M’, ‘-P’, ‘-S’, ‘-q’, ‘-r’, and ‘-R’.
Finally, the _path_files function uses the styles expand,
ambiguous, special-dirs, list-suffixes and file-sort described
above.
_pick_variant [ -c command ] [ -r name ] label=pattern ... label [
args ... ]
This function is used to resolve situations where a single com-
mand name requires more than one type of handling, either
because it has more than one variant or because there is a name
clash between two different commands.
The command to run is taken from the first element of the array
words unless this is overridden by the option -c. This command
is run and its output is compared with a series of patterns.
Arguments to be passed to the command can be specified at the
end after all the other arguments. The patterns to try in
order are given by the arguments label=pattern; if the output
of ‘command args ...’ contains pattern, then label is selected
as the label for the command variant. If none of the patterns
match, the final command label is selected and status 1 is
returned.
If the ‘-r name’ is given, the label picked is stored in the
parameter named name.
The results are also cached in the _cmd_variant associative
array indexed by the name of the command run.
_regex_arguments name spec ...
This function generates a completion function name which
matches the specifications spec ..., a set of regular expres-
sions as described below. After running _regex_arguments, the
function name should be called at the appropriate point. The
pattern to be matched is given by the contents of the words
array up to the current cursor position joined together with
null characters; no quotation is applied.
The arguments are grouped as sets of alternatives separated by
‘|’, which are tried one after the other until one matches.
Each alternative consists of a one or more specifications which
are tried left to right, with each pattern matched being
stripped in turn from the command line being tested, until all
of the group succeeds or until one fails; in the latter case,
the next alternative is tried. This structure can be repeated
to arbitrary depth by using parentheses; matching proceeds from
inside to outside.
A special procedure is applied if no test succeeds but the
remaining command line string contains no null character
(implying the remaining word is the one for which completions
are to be generated). The completion target is restricted to
the remaining word and any actions for the corresponding pat-
terns are executed. In this case, nothing is stripped from the
command line string. The order of evaluation of the actions
can be determined by the tag-order style; the various formats
supported by _alternative can be used in action. The descr is
used for setting up the array parameter expl.
Specification arguments take one of following forms, in which
metacharacters such as ‘(’, ‘)’, ‘#’ and ‘|’ should be quoted.
/pattern/ [%lookahead%] [-guard] [:tag:descr:action]
This is a single primitive component. The function
tests whether the combined pattern ‘(#b)((#B)pat-
tern)lookahead*’ matches the command line string. If
so, ‘guard’ is evaluated and its return status is exam-
ined to determine if the test has succeeded. The pat-
tern string ‘[]’ is guaranteed never to match. The
lookahead is not stripped from the command line before
the next pattern is examined.
/pattern/+ [%lookahead%] [-guard] [:tag:descr:action]
This is similar to ‘/pattern/ ...’ but the left part of
the command line string (i.e. the part already matched
by previous patterns) is also considered part of the
completion target.
/pattern/- [%lookahead%] [-guard] [:tag:descr:action]
This is similar to ‘/pattern/ ...’ but the actions of
the current and previously matched patterns are ignored
even if the following ‘pattern’ matches the empty
string.
( spec )
Parentheses may be used to groups specs; note each
parenthesis is a single argument to _regex_arguments.
spec # This allows any number of repetitions of spec.
spec spec
The two specs are to be matched one after the other as
described above.
spec | spec
Either of the two specs can be matched.
_requested [ -x ] [ -12VJ ] tag [ name descr [ command args ... ] ]
This function is called to decide whether a tag already regis-
tered by a call to _tags (see below) has been requested by the
user and hence completion should be performed for it. It
returns status zero if the tag is requested and non-zero other-
wise. The function is typically used as part of a loop over
different tags as follows:
_tags foo bar baz
while _tags; do
if _requested foo; then
... # perform completion for foo
fi
... # test the tags bar and baz in the same way
... # exit loop if matches were generated
done
Note that the test for whether matches were generated is not
performed until the end of the _tags loop. This is so that the
user can set the tag-order style to specify a set of tags to be
completed at the same time.
If name and descr are given, _requested calls the _description
function with these arguments together with the options passed
to _requested.
If command is given, the _all_labels function will be called
immediately with the same arguments. In simple cases this
makes it possible to perform the test for the tag and the
matching in one go. For example:
local expl ret=1
_tags foo bar baz
while _tags; do
_requested foo expl ’description’ \
compadd foobar foobaz && ret=0
...
(( ret )) || break
done
If the command is not compadd, it must nevertheless be prepared
to handle the same options.
_retrieve_cache cache_identifier
This function retrieves completion information from the file
given by cache_identifier, stored in a directory specified by
the cache-path style which defaults to ~/.zsh/cache. The
return value is zero if retrieval was successful. It will only
attempt retrieval if the use-cache style is set, so you can
call this function without worrying about whether the user
wanted to use the caching layer.
See _store_cache below for more details.
_sep_parts
This function is passed alternating arrays and separators as
arguments. The arrays specify completions for parts of strings
to be separated by the separators. The arrays may be the names
of array parameters or a quoted list of words in parentheses.
For example, with the array ‘hosts=(ftp news)’ the call
‘_sep_parts ’(foo bar)’ @ hosts’ will complete the string ‘f’
to ‘foo’ and the string ‘b@n’ to ‘bar@news’.
This function accepts the compadd options ‘-V’, ‘-J’, ‘-1’,
‘-2’, ‘-n’, ‘-X’, ‘-M’, ‘-P’, ‘-S’, ‘-r’, ‘-R’, and ‘-q’ and
passes them on to the compadd builtin used to add the matches.
_setup tag [ group ]
This function sets up the special parameters used by the com-
pletion system appropriately for the tag given as the first
argument. It uses the styles list-colors, list-packed,
list-rows-first, last-prompt, accept-exact, menu and
force-list.
The optional group supplies the name of the group in which the
matches will be placed. If it is not given, the tag is used as
the group name.
This function is called automatically from _description and
hence is not normally called explicitly.
_store_cache cache_identifier params ...
This function, together with _retrieve_cache and
_cache_invalid, implements a caching layer which can be used in
any completion function. Data obtained by costly operations
are stored in parameters; this function then dumps the values
of those parameters to a file. The data can then be retrieved
quickly from that file via _retrieve_cache, even in different
instances of the shell.
The cache_identifier specifies the file which the data should
be dumped to. The file is stored in a directory specified by
the cache-path style which defaults to ~/.zsh/cache. The
remaining params arguments are the parameters to dump to the
file.
The return value is zero if storage was successful. The func-
tion will only attempt storage if the use-cache style is set,
so you can call this function without worrying about whether
the user wanted to use the caching layer.
The completion function may avoid calling _retrieve_cache when
it already has the completion data available as parameters.
However, in that case it should call _cache_invalid to check
whether the data in the parameters and in the cache are still
valid.
See the _perl_modules completion function for a simple example
of the usage of the caching layer.
_tags [ [ -C name ] tags ... ]
If called with arguments, these are taken to be the names of
tags valid for completions in the current context. These tags
are stored internally and sorted by using the tag-order style.
Next, _tags is called repeatedly without arguments from the
same completion function. This successively selects the first,
second, etc. set of tags requested by the user. The return
value is zero if at least one of the tags is requested and
non-zero otherwise. To test if a particular tag is to be
tried, the _requested function should be called (see above).
If ‘-C name’ is given, name is temporarily stored in the argu-
ment field (the fifth) of the context in the curcontext parame-
ter during the call to _tags; the field is restored on exit.
This allows _tags to use a more specific context without having
to change and reset the curcontext parameter (which has the
same effect).
_values [ -O name ] [ -s sep ] [ -S sep ] [ -wC ] desc spec ...
This is used to complete arbitrary keywords (values) and their
arguments, or lists of such combinations.
If the first argument is the option ‘-O name’, it will be used
in the same way as by the _arguments function. In other words,
the elements of the name array will be passed to compadd when
executing an action.
If the first argument (or the first argument after ‘-O name’)
is ‘-s’, the next argument is used as the character that sepa-
rates multiple values. This character is automatically added
after each value in an auto-removable fashion (see below); all
values completed by ‘_values -s’ appear in the same word on the
command line, unlike completion using _arguments. If this
option is not present, only a single value will be completed
per word.
Normally, _values will only use the current word to determine
which values are already present on the command line and hence
are not to be completed again. If the -w option is given,
other arguments are examined as well.
The first non-option argument is used as a string to print as a
description before listing the values.
All other arguments describe the possible values and their
arguments in the same format used for the description of
options by the _arguments function (see above). The only dif-
ferences are that no minus or plus sign is required at the
beginning, values can have only one argument, and the forms of
action beginning with an equal sign are not supported.
The character separating a value from its argument can be set
using the option -S (like -s, followed by the character to use
as the separator in the next argument). By default the equals
sign will be used as the separator between values and argu-
ments.
Example:
_values -s , ’description’ \
’*foo[bar]’ \
’(two)*one[number]:first count:’ \
’two[another number]::second count:(1 2 3)’
This describes three possible values: ‘foo’, ‘one’, and ‘two’.
The first is described as ‘bar’, takes no argument and may
appear more than once. The second is described as ‘number’,
may appear more than once, and takes one mandatory argument
described as ‘first count’; no action is specified, so it will
not be completed. The ‘(two)’ at the beginning says that if
the value ‘one’ is on the line, the value ‘two’ will no longer
be considered a possible completion. Finally, the last value
(‘two’) is described as ‘another number’ and takes an optional
argument described as ‘second count’ for which the completions
(to appear after an ‘=’) are ‘1’, ‘2’, and ‘3’. The _values
function will complete lists of these values separated by com-
mas.
Like _arguments, this function temporarily adds another context
name component to the arguments element (the fifth) of the cur-
rent context while executing the action. Here this name is
just the name of the value for which the argument is completed.
The style verbose is used to decide if the descriptions for the
values (but not those for the arguments) should be printed.
The associative array val_args is used to report values and
their arguments; this works similarly to the opt_args associa-
tive array used by _arguments. Hence the function calling
_values should declare the local parameters state, line, con-
text and val_args:
local context state line
typeset -A val_args
when using an action of the form ‘->string’. With this func-
tion the context parameter will be set to the name of the value
whose argument is to be completed.
Note also that _values normally adds the character used as the
separator between values as an auto-removable suffix (similar
to a ‘/’ after a directory). However, this is not possible for
a ‘->string’ action as the matches for the argument are gener-
ated by the calling function. To get the usual behaviour, the
the calling function can add the separator x as a suffix by
passing the options ‘-qS x’ either directly or indirectly to
compadd.
The option -C is treated in the same way as it is by _argu-
ments. In that case the parameter curcontext should be made
local instead of context (as described above).
_wanted [ -x ] [ -C name ] [ -12VJ ] tag name descr command args ...
In many contexts, completion can only generate one particular
set of matches, usually corresponding to a single tag. How-
ever, it is still necessary to decide whether the user requires
matches of this type. This function is useful in such a case.
The arguments to _wanted are the same as those to _requested,
i.e. arguments to be passed to _description. However, in this
case the command is not optional; all the processing of tags,
including the loop over both tags and tag labels and the gener-
ation of matches, is carried out automatically by _wanted.
Hence to offer only one tag and immediately add the correspond-
ing matches with the given description:
_wanted tag expl ’description’ \
compadd matches...
Note that, as for _requested, the command must be able to
accept options to be passed down to compadd.
Like _tags this function supports the -C option to give a dif-
ferent name for the argument context field. The -x option has
the same meaning as for _description.
COMPLETION DIRECTORIES
In the source distribution, the files are contained in various subdi-
rectories of the Completion directory. They may have been installed
in the same structure, or into one single function directory. The
following is a description of the files found in the original direc-
tory structure. If you wish to alter an installed file, you will need
to copy it to some directory which appears earlier in your fpath than
the standard directory where it appears.
Base The core functions and special completion widgets automatically
bound to keys. You will certainly need most of these, though
will probably not need to alter them. Many of these are docu-
mented above.
Zsh Functions for completing arguments of shell builtin commands
and utility functions for this. Some of these are also used by
functions from the Unix directory.
Unix Functions for completing arguments of external commands and
suites of commands. They may need modifying for your system,
although in many cases some attempt is made to decide which
version of a command is present. For example, completion for
the mount command tries to determine the system it is running
on, while completion for many other utilities try to decide
whether the GNU version of the command is in use, and hence
whether the --help option is supported.
X, AIX, BSD, ...
Completion and utility function for commands available only on
some systems. These are not arranged hierarchically, so, for
example, both the Linux and Debian directories, as well as the
ZSHCOMPCTL(1) ZSHCOMPCTL(1)
X directory, may be useful on your system.
NAME
zshcompctl - zsh programmable completion
DESCRIPTION
This version of zsh has two ways of performing completion of words on
the command line. New users of the shell may prefer to use the newer
and more powerful system based on shell functions; this is described
in zshcompsys(1), and the basic shell mechanisms which support it are
described in zshcompwid(1). This manual entry describes the older
compctl command.
compctl [ -CDT ] options [ command ... ]
compctl [ -CDT ] options [ -x pattern options - ... -- ] [ + options [
-x ... -- ] ... [+] ] [ command ... ]
compctl -M match-specs ...
compctl -L [ -CDTM ] [ command ... ]
compctl + command ...
Control the editor’s completion behavior according to the supplied set
of options. Various editing commands, notably expand-or-com-
plete-word, usually bound to tab, will attempt to complete a word
typed by the user, while others, notably delete-char-or-list, usually
bound to ^D in EMACS editing mode, list the possibilities; compctl
controls what those possibilities are. They may for example be file-
names (the most common case, and hence the default), shell variables,
or words from a user-specified list.
COMMAND FLAGS
Completion of the arguments of a command may be different for each
command or may use the default. The behavior when completing the com-
mand word itself may also be separately specified. These correspond
to the following flags and arguments, all of which (except for -L) may
be combined with any combination of the options described subsequently
in the section ‘Option Flags’:
command ...
controls completion for the named commands, which must be
listed last on the command line. If completion is attempted
for a command with a pathname containing slashes and no comple-
tion definition is found, the search is retried with the last
pathname component. If the command starts with a =, completion
is tried with the pathname of the command.
Any of the command strings may be patterns of the form normally
used for filename generation. These should be be quoted to
protect them from immediate expansion; for example the command
string ’foo*’ arranges for completion of the words of any com-
mand beginning with foo. When completion is attempted, all
pattern completions are tried in the reverse order of their
definition until one matches. By default, completion then pro-
ceeds as normal, i.e. the shell will try to generate more
matches for the specific command on the command line; this can
be overridden by including -tn in the flags for the pattern
completion.
Note that aliases are expanded before the command name is
determined unless the COMPLETE_ALIASES option is set. Commands
may not be combined with the -C, -D or -T flags.
-C controls completion when the command word itself is being com-
pleted. If no compctl -C command has been issued, the names
of any executable command (whether in the path or specific to
the shell, such as aliases or functions) are completed.
-D controls default completion behavior for the arguments of com-
mands not assigned any special behavior. If no compctl -D com-
mand has been issued, filenames are completed.
-T supplies completion flags to be used before any other process-
ing is done, even before processing for compctls defined for
specific commands. This is especially useful when combined
with extended completion (the -x flag, see the section
‘Extended Completion’ below). Using this flag you can define
default behavior which will apply to all commands without
exception, or you can alter the standard behavior for all com-
mands. For example, if your access to the user database is too
slow and/or it contains too many users (so that completion
after ‘~’ is too slow to be usable), you can use
compctl -T -x ’s[~] C[0,[^/]#]’ -k friends -S/ -tn
to complete the strings in the array friends after a ‘~’. The
C[...] argument is necessary so that this form of ~-completion
is not tried after the directory name is finished.
-L lists the existing completion behavior in a manner suitable for
putting into a start-up script; the existing behavior is not
changed. Any combination of the above forms, or the -M flag
(which must follow the -L flag), may be specified, otherwise
all defined completions are listed. Any other flags supplied
are ignored.
no argument
If no argument is given, compctl lists all defined completions
in an abbreviated form; with a list of options, all comple-
tions with those flags set (not counting extended completion)
are listed.
If the + flag is alone and followed immediately by the command list,
the completion behavior for all the commands in the list is reset to
the default. In other words, completion will subsequently use the
options specified by the -D flag.
The form with -M as the first and only option defines global matching
specifications (see zshcompwid). The match specifications given will
be used for every completion attempt (only when using compctl, not
with the new completion system) and are tried in the order in which
they are defined until one generates at least one match. E.g.:
compctl -M ’’ ’m:{a-zA-Z}={A-Za-z}’
This will first try completion without any global match specifications
(the empty string) and, if that generates no matches, will try case
insensitive completion.
OPTION FLAGS
[ -fcFBdeaRGovNAIOPZEnbjrzu/12 ]
[ -k array ] [ -g globstring ] [ -s subststring ]
[ -K function ]
[ -Q ] [ -P prefix ] [ -S suffix ]
[ -W file-prefix ] [ -H num pattern ]
[ -q ] [ -X explanation ] [ -Y explanation ]
[ -y func-or-var ] [ -l cmd ] [ -h cmd ] [ -U ]
[ -t continue ] [ -J name ] [ -V name ]
[ -M match-spec ]
The remaining options specify the type of command arguments to look
for during completion. Any combination of these flags may be speci-
fied; the result is a sorted list of all the possibilities. The
options are as follows.
Simple Flags
These produce completion lists made up by the shell itself:
-f Filenames and filesystem paths.
-/ Just filesystem paths.
-c Command names, including aliases, shell functions, builtins and
reserved words.
-F Function names.
-B Names of builtin commands.
-m Names of external commands.
-w Reserved words.
-a Alias names.
-R Names of regular (non-global) aliases.
-G Names of global aliases.
-d This can be combined with -F, -B, -w, -a, -R and -G to get
names of disabled functions, builtins, reserved words or
aliases.
-e This option (to show enabled commands) is in effect by default,
but may be combined with -d; -de in combination with -F, -B,
-w, -a, -R and -G will complete names of functions, builtins,
reserved words or aliases whether or not they are disabled.
-o Names of shell options (see zshoptions(1)).
-v Names of any variable defined in the shell.
-N Names of scalar (non-array) parameters.
-A Array names.
-I Names of integer variables.
-O Names of read-only variables.
-p Names of parameters used by the shell (including special param-
eters).
-Z Names of shell special parameters.
-E Names of environment variables.
-n Named directories.
-b Key binding names.
-j Job names: the first word of the job leader’s command line.
This is useful with the kill builtin.
-r Names of running jobs.
-z Names of suspended jobs.
-u User names.
Flags with Arguments
These have user supplied arguments to determine how the list of com-
pletions is to be made up:
-k array
Names taken from the elements of $array (note that the ‘$’ does
not appear on the command line). Alternatively, the argument
array itself may be a set of space- or comma-separated values
in parentheses, in which any delimiter may be escaped with a
backslash; in this case the argument should be quoted. For
example,
compctl -k "(cputime filesize datasize stacksize
coredumpsize resident descriptors)" limit
-g globstring
The globstring is expanded using filename globbing; it should
be quoted to protect it from immediate expansion. The resulting
filenames are taken as the possible completions. Use ‘*(/)’
instead of ‘*/’ for directories. The fignore special parameter
is not applied to the resulting files. More than one pattern
may be given separated by blanks. (Note that brace expansion is
not part of globbing. Use the syntax ‘(either|or)’ to match
alternatives.)
-s subststring
The subststring is split into words and these words are than
expanded using all shell expansion mechanisms (see zshexpn(1)).
The resulting words are taken as possible completions. The
fignore special parameter is not applied to the resulting
files. Note that -g is faster for filenames.
-K function
Call the given function to get the completions. Unless the
name starts with an underscore, the function is passed two
arguments: the prefix and the suffix of the word on which com-
pletion is to be attempted, in other words those characters
before the cursor position, and those from the cursor position
onwards. The whole command line can be accessed with the -c
and -l flags of the read builtin. The function should set the
variable reply to an array containing the completions (one com-
pletion per element); note that reply should not be made local
to the function. From such a function the command line can be
accessed with the -c and -l flags to the read builtin. For
example,
function whoson { reply=(‘users‘); }
compctl -K whoson talk
completes only logged-on users after ‘talk’. Note that ‘who-
son’ must return an array, so ‘reply=‘users‘’ would be incor-
rect.
-H num pattern
The possible completions are taken from the last num history
lines. Only words matching pattern are taken. If num is zero
or negative the whole history is searched and if pattern is the
empty string all words are taken (as with ‘*’). A typical use
is
compctl -D -f + -H 0 ’’
which forces completion to look back in the history list for a
word if no filename matches.
Control Flags
These do not directly specify types of name to be completed, but
manipulate the options that do:
-Q This instructs the shell not to quote any metacharacters in the
possible completions. Normally the results of a completion are
inserted into the command line with any metacharacters quoted
so that they are interpreted as normal characters. This is
appropriate for filenames and ordinary strings. However, for
special effects, such as inserting a backquoted expression from
a completion array (-k) so that the expression will not be
evaluated until the complete line is executed, this option must
be used.
-P prefix
The prefix is inserted just before the completed string; any
initial part already typed will be completed and the whole pre-
fix ignored for completion purposes. For example,
compctl -j -P "%" kill
inserts a ‘%’ after the kill command and then completes job
names.
-S suffix
When a completion is found the suffix is inserted after the
completed string. In the case of menu completion the suffix is
inserted immediately, but it is still possible to cycle through
the list of completions by repeatedly hitting the same key.
-W file-prefix
With directory file-prefix: for command, file, directory and
globbing completion (options -c, -f, -/, -g), the file prefix
is implicitly added in front of the completion. For example,
compctl -/ -W ~/Mail maildirs
completes any subdirectories to any depth beneath the directory
~/Mail, although that prefix does not appear on the command
line. The file-prefix may also be of the form accepted by the
-k flag, i.e. the name of an array or a literal list in paren-
thesis. In this case all the directories in the list will be
searched for possible completions.
-q If used with a suffix as specified by the -S option, this
causes the suffix to be removed if the next character typed is
a blank or does not insert anything or if the suffix consists
of only one character and the next character typed is the same
character; this the same rule used for the AUTO_REMOVE_SLASH
option. The option is most useful for list separators (comma,
colon, etc.).
-l cmd This option restricts the range of command line words that are
considered to be arguments. If combined with one of the
extended completion patterns ‘p[...]’, ‘r[...]’, or ‘R[...]’
(see the section ‘Extended Completion’ below) the range is
restricted to the range of arguments specified in the brackets.
Completion is then performed as if these had been given as
arguments to the cmd supplied with the option. If the cmd
string is empty the first word in the range is instead taken as
the command name, and command name completion performed on the
first word in the range. For example,
compctl -x ’r[-exec,;]’ -l ’’ -- find
completes arguments between ‘-exec’ and the following ‘;’ (or
the end of the command line if there is no such string) as if
they were a separate command line.
-h cmd Normally zsh completes quoted strings as a whole. With this
option, completion can be done separately on different parts of
such strings. It works like the -l option but makes the comple-
tion code work on the parts of the current word that are sepa-
rated by spaces. These parts are completed as if they were
arguments to the given cmd. If cmd is the empty string, the
first part is completed as a command name, as with -l.
-U Use the whole list of possible completions, whether or not they
actually match the word on the command line. The word typed so
far will be deleted. This is most useful with a function
(given by the -K option) which can examine the word components
passed to it (or via the read builtin’s -c and -l flags) and
use its own criteria to decide what matches. If there is no
completion, the original word is retained. Since the produced
possible completions seldom have interesting common prefixes
and suffixes, menu completion is started immediately if
AUTO_MENU is set and this flag is used.
-y func-or-var
The list provided by func-or-var is displayed instead of the
list of completions whenever a listing is required; the actual
completions to be inserted are not affected. It can be pro-
vided in two ways. Firstly, if func-or-var begins with a $ it
defines a variable, or if it begins with a left parenthesis a
literal array, which contains the list. A variable may have
been set by a call to a function using the -K option. Other-
wise it contains the name of a function which will be executed
to create the list. The function will be passed as an argument
list all matching completions, including prefixes and suffixes
expanded in full, and should set the array reply to the result.
In both cases, the display list will only be retrieved after a
complete list of matches has been created.
Note that the returned list does not have to correspond, even
in length, to the original set of matches, and may be passed as
a scalar instead of an array. No special formatting of charac-
ters is performed on the output in this case; in particular,
newlines are printed literally and if they appear output in
columns is suppressed.
-X explanation
Print explanation when trying completion on the current set of
options. A ‘%n’ in this string is replaced by the number of
matches that were added for this explanation string. The
explanation only appears if completion was tried and there was
no unique match, or when listing completions. Explanation
strings will be listed together with the matches of the group
specified together with the -X option (using the -J or -V
option). If the same explanation string is given to multiple -X
options, the string appears only once (for each group) and the
number of matches shown for the ‘%n’ is the total number of all
matches for each of these uses. In any case, the explanation
string will only be shown if there was at least one match added
for the explanation string.
The sequences %B, %b, %S, %s, %U, and %u specify output
attributes (bold, standout, and underline) and %{...%} can be
used to include literal escape sequences as in prompts.
-Y explanation
Identical to -X, except that the explanation first undergoes
expansion following the usual rules for strings in double
quotes. The expansion will be carried out after any functions
are called for the -K or -y options, allowing them to set vari-
ables.
-t continue
The continue-string contains a character that specifies which
set of completion flags should be used next. It is useful:
(i) With -T, or when trying a list of pattern completions, when
compctl would usually continue with ordinary processing after
finding matches; this can be suppressed with ‘-tn’.
(ii) With a list of alternatives separated by +, when compctl
would normally stop when one of the alternatives generates
matches. It can be forced to consider the next set of comple-
tions by adding ‘-t+’ to the flags of the alternative before
the ‘+’.
(iii) In an extended completion list (see below), when compctl
would normally continue until a set of conditions succeeded,
then use only the immediately following flags. With ‘-t-’,
compctl will continue trying extended completions after the
next ‘-’; with ‘-tx’ it will attempt completion with the
default flags, in other words those before the ‘-x’.
-J name
This gives the name of the group the matches should be placed
in. Groups are listed and sorted separately; likewise, menu
completion will offer the matches in the groups in the order in
which the groups were defined. If no group name is explicitly
given, the matches are stored in a group named default. The
first time a group name is encountered, a group with that name
is created. After that all matches with the same group name are
stored in that group.
This can be useful with non-exclusive alternative completions.
For example, in
compctl -f -J files -t+ + -v -J variables foo
both files and variables are possible completions, as the -t+
forces both sets of alternatives before and after the + to be
considered at once. Because of the -J options, however, all
files are listed before all variables.
-V name
Like -J, but matches within the group will not be sorted in
listings nor in menu completion. These unsorted groups are in a
different name space from the sorted ones, so groups defined as
-J files and -V files are distinct.
-1 If given together with the -V option, makes only consecutive
duplicates in the group be removed. Note that groups with and
without this flag are in different name spaces.
-2 If given together with the -J or -V option, makes all dupli-
cates be kept. Again, groups with and without this flag are in
different name spaces.
-M match-spec
This defines additional matching control specifications that
should be used only when testing words for the list of flags
this flag appears in. The format of the match-spec string is
described in zshcompwid.
ALTERNATIVE COMPLETION
compctl [ -CDT ] options + options [ + ... ] [ + ] command ...
The form with ‘+’ specifies alternative options. Completion is tried
with the options before the first ‘+’. If this produces no matches
completion is tried with the flags after the ‘+’ and so on. If there
are no flags after the last ‘+’ and a match has not been found up to
that point, default completion is tried. If the list of flags con-
tains a -t with a + character, the next list of flags is used even if
the current list produced matches.
EXTENDED COMPLETION
compctl [ -CDT ] options -x pattern options - ... --
[ command ... ]
compctl [ -CDT ] options [ -x pattern options - ... -- ]
[ + options [ -x ... -- ] ... [+] ] [ command ... ]
The form with ‘-x’ specifies extended completion for the commands
given; as shown, it may be combined with alternative completion using
‘+’. Each pattern is examined in turn; when a match is found, the
corresponding options, as described in the section ‘Option Flags’
above, are used to generate possible completions. If no pattern
matches, the options given before the -x are used.
Note that each pattern should be supplied as a single argument and
should be quoted to prevent expansion of metacharacters by the shell.
A pattern is built of sub-patterns separated by commas; it matches if
at least one of these sub-patterns matches (they are ‘or’ed). These
sub-patterns are in turn composed of other sub-patterns separated by
white spaces which match if all of the sub-patterns match (they are
‘and’ed). An element of the sub-patterns is of the form
‘c[...][...]’, where the pairs of brackets may be repeated as often as
necessary, and matches if any of the sets of brackets match (an ‘or’).
The example below makes this clearer.
The elements may be any of the following:
s[string]...
Matches if the current word on the command line starts with one
of the strings given in brackets. The string is not removed
and is not part of the completion.
S[string]...
Like s[string] except that the string is part of the comple-
tion.
p[from,to]...
Matches if the number of the current word is between one of the
from and to pairs inclusive. The comma and to are optional; to
defaults to the same value as from. The numbers may be nega-
tive: -n refers to the n’th last word on the line.
c[offset,string]...
Matches if the string matches the word offset by offset from
the current word position. Usually offset will be negative.
C[offset,pattern]...
Like c but using pattern matching instead.
w[index,string]...
Matches if the word in position index is equal to the corre-
sponding string. Note that the word count is made after any
alias expansion.
W[index,pattern]...
Like w but using pattern matching instead.
n[index,string]...
Matches if the current word contains string. Anything up to
and including the indexth occurrence of this string will not be
considered part of the completion, but the rest will. index
may be negative to count from the end: in most cases, index
will be 1 or -1. For example,
compctl -s ’‘users‘’ -x ’n[1,@]’ -k hosts -- talk
will usually complete usernames, but if you insert an @ after
the name, names from the array hosts (assumed to contain host-
names, though you must make the array yourself) will be com-
pleted. Other commands such as rcp can be handled similarly.
N[index,string]...
Like n except that the string will be taken as a character
class. Anything up to and including the indexth occurrence of
any of the characters in string will not be considered part of
the completion.
m[min,max]...
Matches if the total number of words lies between min and max
inclusive.
r[str1,str2]...
Matches if the cursor is after a word with prefix str1. If
there is also a word with prefix str2 on the command line after
the one matched by str1 it matches only if the cursor is before
this word. If the comma and str2 are omitted, it matches if the
cursor is after a word with prefix str1.
R[str1,str2]...
Like r but using pattern matching instead.
q[str]...
Matches the word currently being completed is in single quotes
and the str begins with the letter ‘s’, or if completion is
done in double quotes and str starts with the letter ‘d’, or if
completion is done in backticks and str starts with a ‘b’.
EXAMPLE
compctl -u -x ’s[+] c[-1,-f],s[-f+]’ \
-g ’~/Mail/*(:t)’ - ’s[-f],c[-1,-f]’ -f -- mail
This is to be interpreted as follows:
If the current command is mail, then
if ((the current word begins with + and the previous word is -f)
or (the current word begins with -f+)), then complete the
non-directory part (the ‘:t’ glob modifier) of files in the directory
~/Mail; else
if the current word begins with -f or the previous word was -f, then
complete any file; else
complete user names.
ZSHMODULES(1) ZSHMODULES(1)
NAME
zshmodules - zsh loadable modules
DESCRIPTION
Some optional parts of zsh are in modules, separate from the core of
the shell. Each of these modules may be linked in to the shell at
build time, or can be dynamically linked while the shell is running if
the installation supports this feature. The modules that are bundled
with the zsh distribution are:
zsh/cap
Builtins for manipulating POSIX.1e (POSIX.6) capability (privi-
lege) sets.
zsh/clone
A builtin that can clone a running shell onto another terminal.
zsh/compctl
The compctl builtin for controlling completion.
zsh/complete
The basic completion code.
zsh/complist
Completion listing extensions.
zsh/computil
A module with utility builtins needed for the shell function
based completion system.
zsh/datetime
Some date/time commands and parameters.
zsh/deltochar
A ZLE function duplicating EMACS’ zap-to-char.
zsh/example
An example of how to write a module.
zsh/files
Some basic file manipulation commands as builtins.
zsh/mapfile
Access to external files via a special associative array.
zsh/mathfunc
Standard scientific functions for use in mathematical evalua-
tions.
zsh/parameter
Access to internal hash tables via special associative arrays.
zsh/pcre
Interface to the PCRE library.
zsh/sched
A builtin that provides a timed execution facility within the
shell.
zsh/net/socket
Manipulation of Unix domain sockets
zsh/stat
A builtin command interface to the stat system call.
zsh/system
A builtin interface to various low-level system features.
zsh/net/tcp
Manipulation of TCP sockets
zsh/termcap
Interface to the termcap database.
zsh/terminfo
Interface to the terminfo database.
zsh/zftp
A builtin FTP client.
zsh/zle
The Zsh Line Editor, including the bindkey and vared builtins.
zsh/zleparameter
Access to internals of the Zsh Line Editor via parameters.
zsh/zprof
A module allowing profiling for shell functions.
zsh/zpty
A builtin for starting a command in a pseudo-terminal.
zsh/zselect
Block and return when file descriptors are ready.
zsh/zutil
Some utility builtins, e.g. the one for supporting configura-
tion via styles.
THE ZSH/CAP MODULE
The zsh/cap module is used for manipulating POSIX.1e (POSIX.6) capa-
bility sets. If the operating system does not support this interface,
the builtins defined by this module will do nothing. The builtins in
this module are:
cap [ capabilities ]
Change the shell’s process capability sets to the specified
capabilities, otherwise display the shell’s current capabili-
ties.
getcap filename ...
This is a built-in implementation of the POSIX standard util-
ity. It displays the capability sets on each specified file-
name.
setcap capabilities filename ...
This is a built-in implementation of the POSIX standard util-
ity. It sets the capability sets on each specified filename to
the specified capabilities.
THE ZSH/CLONE MODULE
The zsh/clone module makes available one builtin command:
clone tty
Creates a forked instance of the current shell, attached to the
specified tty. In the new shell, the PID, PPID and TTY special
parameters are changed appropriately. $! is set to zero in the
new shell, and to the new shell’s PID in the original shell.
The return value of the builtin is zero in both shells if suc-
cessful, and non-zero on error.
THE ZSH/COMPCTL MODULE
The zsh/compctl module makes available two builtin commands. compctl,
is the old, deprecated way to control completions for ZLE. See zsh-
compctl(1). The other builtin command, compcall can be used in
user-defined completion widgets, see zshcompwid(1).
THE ZSH/COMPLETE MODULE
The zsh/complete module makes available several builtin commands which
can be used in user-defined completion widgets, see zshcompwid(1).
THE ZSH/COMPLIST MODULE
The zsh/complist module offers three extensions to completion list-
ings: the ability to highlight matches in such a list, the ability to
scroll through long lists and a different style of menu completion.
Colored completion listings
Whenever one of the parameters ZLS_COLORS or ZLS_COLOURS is set and
the zsh/complist module is loaded or linked into the shell, completion
lists will be colored. Note, however, that complist will not automat-
ically be loaded if it is not linked in: on systems with dynamic
loading, ‘zmodload zsh/complist’ is required.
The parameters ZLS_COLORS and ZLS_COLOURS describe how matches are
highlighted. To turn on highlighting an empty value suffices, in
which case all the default values given below will be used. The for-
mat of the value of these parameters is the same as used by the GNU
version of the ls command: a colon-separated list of specifications of
the form ‘name=value’. The name may be one of the following strings,
most of which specify file types for which the value will be used.
The strings and their default values are:
no 0 for normal text (i.e. when displaying something other than a
matched file)
fi 0 for regular files
di 32 for directories
ln 36 for symbolic links
pi 31 for named pipes (FIFOs)
so 33 for sockets
bd 44;37
for block devices
cd 44;37
for character devices
ex 35 for executable files
mi none
for a non-existent file (default is the value defined for fi)
lc \e[ for the left code (see below)
rc m for the right code
tc 0 for the character indicating the file type printed after file-
names if the LIST_TYPES option is set
sp 0 for the spaces printed after matches to align the next column
ec none
for the end code
Apart from these strings, the name may also be an asterisk (‘*’) fol-
lowed by any string. The value given for such a string will be used
for all files whose name ends with the string. The name may also be
an equals sign (‘=’) followed by a pattern. The value given for this
pattern will be used for all matches (not just filenames) whose dis-
play string are matched by the pattern. Definitions for both of these
take precedence over the values defined for file types and the form
with the leading asterisk takes precedence over the form with the
leading equal sign.
The last form also allows different parts of the displayed strings to
be colored differently. For this, the pattern has to use the ‘(#b)’
globbing flag and pairs of parentheses surrounding the parts of the
strings that are to be colored differently. In this case the value
may consist of more than one color code separated by equal signs. The
first code will be used for all parts for which no explicit code is
specified and the following codes will be used for the parts matched
by the sub-patterns in parentheses. For example, the specification
‘=(#b)(?)*(?)=0=3=7’ will be used for all matches which are at least
two characters long and will use the code ‘3’ for the first character,
‘7’ for the last character and ‘0’ for the rest.
All three forms of name may be preceded by a pattern in parentheses.
If this is given, the value will be used only for matches in groups
whose names are matched by the pattern given in the parentheses. For
example, ‘(g*)m*=43’ highlights all matches beginning with ‘m’ in
groups whose names begin with ‘g’ using the color code ‘43’. In case
of the ‘lc’, ‘rc’, and ‘ec’ codes, the group pattern is ignored.
Note also that all patterns are tried in the order in which they
appear in the parameter value until the first one matches which is
then used.
When printing a match, the code prints the value of lc, the value for
the file-type or the last matching specification with a ‘*’, the value
of rc, the string to display for the match itself, and then the value
of ec if that is defined or the values of lc, no, and rc if ec is not
defined.
The default values are ISO 6429 (ANSI) compliant and can be used on
vt100 compatible terminals such as xterms. On monochrome terminals
the default values will have no visible effect. The colors function
from the contribution can be used to get associative arrays containing
the codes for ANSI terminals (see the section ‘Other Functions’ in
zshcontrib(1)). For example, after loading colors, one could use
‘$colors[red]’ to get the code for foreground color red and ‘$col-
ors[bg-green]’ for the code for background color green.
If the completion system invoked by compinit is used, these parameters
should not be set directly because the system controls them itself.
Instead, the list-colors style should be used (see the section ‘Com-
pletion System Configuration’ in zshcompsys(1)).
Scrolling in completion listings
To enable scrolling through a completion list, the LISTPROMPT parame-
ter must be set. Its value will be used as the prompt; if it is the
empty string, a default prompt will be used. The value may contain
escapes of the form ‘%x’. It supports the escapes ‘%B’, ‘%b’, ‘%S’,
‘%s’, ‘%U’, ‘%u’ and ‘%{...%}’ used also in shell prompts as well as
three pairs of additional sequences: a ‘%l’ or ‘%L’ is replaced by the
number of the last line shown and the total number of lines in the
form ‘number/total’; a ‘%m’ or ‘%M’ is replaced with the number of the
last match shown and the total number of matches; and ‘%p’ or ‘%P’ is
replaced with ‘Top’, ‘Bottom’ or the position of the first line shown
in percent of the total number of lines, respectively. In each of
these cases the form with the uppercase letter will be replaced with a
string of fixed width, padded to the right with spaces, while the low-
ercase form will not be padded.
If the parameter LISTPROMPT is set, the completion code will not ask
if the list should be shown. Instead it immediately starts displaying
the list, stopping after the first screenful, showing the prompt at
the bottom, waiting for a keypress after temporarily switching to the
listscroll keymap. Some of the zle functions have a special meaning
while scrolling lists:
send-break
stops listing discarding the key pressed
accept-line, down-history, down-line-or-history
down-line-or-search, vi-down-line-or-history
scrolls forward one line
complete-word, menu-complete, expand-or-complete
expand-or-complete-prefix, menu-complete-or-expand
scrolls forward one screenful
Every other character stops listing and immediately processes the key
as usual. Any key that is not bound in the listscroll keymap or that
is bound to undefined-key is looked up in the keymap currently
selected.
As for the ZLS_COLORS and ZLS_COLOURS parameters, LISTPROMPT should
not be set directly when using the shell function based completion
system. Instead, the list-prompt style should be used.
Menu selection
The zsh/complist module also offers an alternative style of selecting
matches from a list, called menu selection, which can be used if the
shell is set up to return to the last prompt after showing a comple-
tion list (see the ALWAYS_LAST_PROMPT option in zshoptions(1)). It
can be invoked directly by the widget menu-select defined by the mod-
ule. Alternatively, the parameter MENUSELECT can be set to an inte-
ger, which gives the minimum number of matches that must be present
before menu selection is automatically turned on. This second method
requires that menu completion be started, either directly from a wid-
get such as menu-complete, or due to one of the options MENU_COMPLETE
or AUTO_MENU being set. If MENUSELECT is set, but is 0, 1 or empty,
menu selection will always be started during an ambiguous menu comple-
tion.
When using the completion system based on shell functions, the MENUSE-
LECT parameter should not be used (like the ZLS_COLORS and ZLS_COLOURS
parameters described above). Instead, the menu style should be used
with the select=... keyword.
After menu selection is started, the matches will be listed. If there
are more matches than fit on the screen, only the first screenful is
shown. The matches to insert into the command line can be selected
from this list. In the list one match is highlighted using the value
for ma from the ZLS_COLORS or ZLS_COLOURS parameter. The default
value for this is ‘7’ which forces the selected match to be high-
lighted using standout mode on a vt100-compatible terminal. If nei-
ther ZLS_COLORS nor ZLS_COLOURS is set, the same terminal control
sequence as for the ‘%S’ escape in prompts is used.
If there are more matches than fit on the screen and the parameter
MENUPROMPT is set, its value will be shown below the matches. It sup-
ports the same escape sequences as LISTPROMPT, but the number of the
match or line shown will be that of the one where the mark is placed.
If its value is the empty string, a default prompt will be used.
The MENUSCROLL parameter can be used to specify how the list is
scrolled. If the parameter is unset, this is done line by line, if it
is set to ‘0’ (zero), the list will scroll half the number of lines of
the screen. If the value is positive, it gives the number of lines to
scroll and if it is negative, the list will be scrolled the number of
lines of the screen minus the (absolute) value.
As for the ZLS_COLORS, ZLS_COLOURS and LISTPROMPT parameters, neither
MENUPROMPT nor MENUSCROLL should be set directly when using the shell
function based completion system. Instead, the select-prompt and
select-scroll styles should be used.
The completion code sometimes decides not to show all of the matches
in the list. These hidden matches are either matches for which the
completion function which added them explicitly requested that they
not appear in the list (using the -n option of the compadd builtin
command) or they are matches which duplicate a string already in the
list (because they differ only in things like prefixes or suffixes
that are not displayed). In the list used for menu selection, how-
ever, even these matches are shown so that it is possible to select
them. To highlight such matches the hi and du capabilities in the
ZLS_COLORS and ZLS_COLOURS parameters are supported for hidden matches
of the first and second kind, respectively.
Selecting matches is done by moving the mark around using the zle
movement functions. When not all matches can be shown on the screen
at the same time, the list will scroll up and down when crossing the
top or bottom line. The following zle functions have special meaning
during menu selection:
accept-line
accepts the current match and leaves menu selection
send-break
leaves menu selection and restores the previous contents of the
command line
redisplay, clear-screen
execute their normal function without leaving menu selection
accept-and-hold, accept-and-menu-complete
accept the currently inserted match and continue selection
allowing to select the next match to insert into the line
accept-and-infer-next-history
accepts the current match and then tries completion with menu
selection again; in the case of files this allows one to
select a directory and immediately attempt to complete files in
it; if there are no matches, a message is shown and one can
use undo to go back to completion on the previous level, every
other key leaves menu selection (including the other zle func-
tions which are otherwise special during menu selection)
undo removes matches inserted during the menu selection by one of
the three functions before
down-history, down-line-or-history
vi-down-line-or-history, down-line-or-search
moves the mark one line down
up-history, up-line-or-history
vi-up-line-or-history, up-line-or-search
moves the mark one line up
forward-char, vi-forward-char
moves the mark one column right
backward-char, vi-backward-char
moves the mark one column left
forward-word, vi-forward-word
vi-forward-word-end, emacs-forward-word
moves the mark one screenful down
backward-word, vi-backward-word, emacs-backward-word
moves the mark one screenful up
vi-forward-blank-word, vi-forward-blank-word-end
moves the mark to the first line of the next group of matches
vi-backward-blank-word
moves the mark to the last line of the previous group of
matches
beginning-of-history
moves the mark to the first line
end-of-history
moves the mark to the last line
beginning-of-buffer-or-history, beginning-of-line
beginning-of-line-hist, vi-beginning-of-line
moves the mark to the leftmost column
end-of-buffer-or-history, end-of-line
end-of-line-hist, vi-end-of-line
moves the mark to the rightmost column
complete-word, menu-complete, expand-or-complete
expand-or-complete-prefix, menu-expand-or-complete
moves the mark to the next match
reverse-menu-complete
moves the mark to the previous match
vi-insert
this toggles between normal and interactive mode; in interac-
tive mode the keys bound to self-insert and self-insert-unmeta
insert into the command line as in normal editing mode but
without leaving menu selection; after each character completion
is tried again and the list changes to contain only the new
matches; the completion widgets make the longest unambiguous
string be inserted in the command line and undo and back-
ward-delete-char go back to the previous set of matches
history-incremental-search-forward,
history-incremental-search-backward this starts incremental
searches in the list of completions displayed; in this mode,
accept-line only leaves incremental search, going back to the
normal menu selection mode
All movement functions wrap around at the edges; any other zle func-
tion not listed leaves menu selection and executes that function. It
is possible to make widgets in the above list do the same by using the
form of the widget with a ‘.’ in front. For example, the widget
‘.accept-line’ has the effect of leaving menu selection and accepting
the entire command line.
During this selection the widget uses the keymap menuselect. Any key
that is not defined in this keymap or that is bound to undefined-key
is looked up in the keymap currently selected. This is used to ensure
that the most important keys used during selection (namely the cursor
keys, return, and TAB) have sensible defaults. However, keys in the
menuselect keymap can be modified directly using the bindkey builtin
command (see zshmodules(1)). For example, to make the return key leave
menu selection without accepting the match currently selected one
could call
bindkey -M menuselect ’^M’ send-break
after loading the zsh/complist module.
THE ZSH/COMPUTIL MODULE
The zsh/computil module adds several builtin commands that are used by
some of the completion functions in the completion system based on
shell functions (see zshcompsys(1) ). Except for compquote these
builtin commands are very specialised and thus not very interesting
when writing your own completion functions. In summary, these builtin
commands are:
comparguments
This is used by the _arguments function to do the argument and
command line parsing. Like compdescribe it has an option -i to
do the parsing and initialize some internal state and various
options to access the state information to decide what should
be completed.
compdescribe
This is used by the _describe function to build the displays
for the matches and to get the strings to add as matches with
their options. On the first call one of the options -i or -I
should be supplied as the first argument. In the first case,
display strings without the descriptions will be generated, in
the second case, the string used to separate the matches from
their descriptions must be given as the second argument and the
descriptions (if any) will be shown. All other arguments are
like the definition arguments to _describe itself.
Once compdescribe has been called with either the -i or the -I
option, it can be repeatedly called with the -g option and the
names of five arrays as its arguments. This will step through
the different sets of matches and store the options in the
first array, the strings with descriptions in the second, the
matches for these in the third, the strings without descrip-
tions in the fourth, and the matches for them in the fifth
array. These are then directly given to compadd to register
the matches with the completion code.
compfiles
Used by the _path_files function to optimize complex recursive
filename generation (globbing). It does three things. With
the -p and -P options it builds the glob patterns to use,
including the paths already handled and trying to optimize the
patterns with respect to the prefix and suffix from the line
and the match specification currently used. The -i option does
the directory tests for the ignore-parents style and the -r
option tests if a component for some of the matches are equal
to the string on the line and removes all other matches if that
is true.
compgroups
Used by the _tags function to implement the internals of the
group-order style. This only takes its arguments as names of
completion groups and creates the groups for it (all six types:
sorted and unsorted, both without removing duplicates, with
removing all duplicates and with removing consecutive dupli-
cates).
compquote [ -p ] names ...
There may be reasons to write completion functions that have to
add the matches using the -Q option to compadd and perform
quoting themselves. Instead of interpreting the first charac-
ter of the all_quotes key of the compstate special association
and using the q flag for parameter expansions, one can use this
builtin command. The arguments are the names of scalar or
array parameters and the values of these parameters are quoted
as needed for the innermost quoting level. If the -p option is
given, quoting is done as if there is some prefix before the
values of the parameters, so that a leading equal sign will not
be quoted.
The return value is non-zero in case of an error and zero oth-
erwise.
comptags
comptry
These implement the internals of the tags mechanism.
compvalues
Like comparguments, but for the _values function.
THE ZSH/DATETIME MODULE
The zsh/datetime module makes available one builtin command:
strftime [ -s scalar ] format epochtime
Output the date denoted by epochtime in the format specified.
If -s scalar is given, assign the date to scalar instead of
printing it.
The zsh/datetime module makes available one parameter:
EPOCHSECONDS
An integer value representing the number of seconds since the
epoch.
THE ZSH/DELTOCHAR MODULE
The zsh/deltochar module makes available two ZLE functions:
delete-to-char
Read a character from the keyboard, and delete from the cursor
position up to and including the next (or, with repeat count n,
the nth) instance of that character. Negative repeat counts
mean delete backwards.
zap-to-char
This behaves like delete-to-char, except that the final occur-
rence of the character itself is not deleted.
THE ZSH/EXAMPLE MODULE
The zsh/example module makes available one builtin command:
example [ -flags ] [ args ... ]
Displays the flags and arguments it is invoked with.
The purpose of the module is to serve as an example of how to write a
module.
THE ZSH/FILES MODULE
The zsh/files module makes some standard commands available as
builtins:
chgrp [ -Rs ] group filename ...
Changes group of files specified. This is equivalent to chown
with a user-spec argument of ‘:group’.
chown [ -Rs ] user-spec filename ...
Changes ownership and group of files specified.
The user-spec can be in four forms:
user change owner to user; do not change group
user:: change owner to user; do not change group
user: change owner to user; change group to user’s primary
group
user:group
change owner to user; change group to group
:group do not change owner; change group to group
In each case, the ‘:’ may instead be a ‘.’. The rule is that
if there is a ‘:’ then the separator is ‘:’, otherwise if there
is a ‘.’ then the separator is ‘.’, otherwise there is no sepa-
rator.
Each of user and group may be either a username (or group name,
as appropriate) or a decimal user ID (group ID). Interpreta-
tion as a name takes precedence, if there is an all-numeric
username (or group name).
The -R option causes chown to recursively descend into directo-
ries, changing the ownership of all files in the directory
after changing the ownership of the directory itself.
The -s option is a zsh extension to chown functionality. It
enables paranoid behaviour, intended to avoid security problems
involving a chown being tricked into affecting files other than
the ones intended. It will refuse to follow symbolic links, so
that (for example) ‘‘chown luser /tmp/foo/passwd’’ can’t acci-
dentally chown /etc/passwd if /tmp/foo happens to be a link to
/etc. It will also check where it is after leaving directo-
ries, so that a recursive chown of a deep directory tree can’t
end up recursively chowning /usr as a result of directories
being moved up the tree.
ln [ -dfis ] filename dest
ln [ -dfis ] filename ... dir
Creates hard (or, with -s, symbolic) links. In the first form,
the specified destination is created, as a link to the speci-
fied filename. In the second form, each of the filenames is
taken in turn, and linked to a pathname in the specified direc-
tory that has the same last pathname component.
Normally, ln will not attempt to create hard links to directo-
ries. This check can be overridden using the -d option. Typi-
cally only the super-user can actually succeed in creating hard
links to directories. This does not apply to symbolic links in
any case.
By default, existing files cannot be replaced by links. The -i
option causes the user to be queried about replacing existing
files. The -f option causes existing files to be silently
deleted, without querying. -f takes precedence.
mkdir [ -p ] [ -m mode ] dir ...
Creates directories. With the -p option, non-existing parent
directories are first created if necessary, and there will be
no complaint if the directory already exists. The -m option
can be used to specify (in octal) a set of file permissions for
the created directories, otherwise mode 777 modified by the
current umask (see umask(2)) is used.
mv [ -fi ] filename dest
mv [ -fi ] filename ... dir
Moves files. In the first form, the specified filename is
moved to the specified destination. In the second form, each
of the filenames is taken in turn, and moved to a pathname in
the specified directory that has the same last pathname compo-
nent.
By default, the user will be queried before replacing any file
that the user cannot write to, but writable files will be
silently removed. The -i option causes the user to be queried
about replacing any existing files. The -f option causes any
existing files to be silently deleted, without querying. -f
takes precedence.
Note that this mv will not move files across devices. Histori-
cal versions of mv, when actual renaming is impossible, fall
back on copying and removing files; if this behaviour is
desired, use cp and rm manually. This may change in a future
version.
rm [ -dfirs ] filename ...
Removes files and directories specified.
Normally, rm will not remove directories (except with the -r
option). The -d option causes rm to try removing directories
with unlink (see unlink(2)), the same method used for files.
Typically only the super-user can actually succeed in unlinking
directories in this way. -d takes precedence over -r.
By default, the user will be queried before removing any file
that the user cannot write to, but writable files will be
silently removed. The -i option causes the user to be queried
about removing any files. The -f option causes files to be
silently deleted, without querying, and suppresses all error
indications. -f takes precedence.
The -r option causes rm to recursively descend into directo-
ries, deleting all files in the directory before removing the
directory with the rmdir system call (see rmdir(2)).
The -s option is a zsh extension to rm functionality. It
enables paranoid behaviour, intended to avoid common security
problems involving a root-run rm being tricked into removing
files other than the ones intended. It will refuse to follow
symbolic links, so that (for example) ‘‘rm /tmp/foo/passwd’’
can’t accidentally remove /etc/passwd if /tmp/foo happens to be
a link to /etc. It will also check where it is after leaving
directories, so that a recursive removal of a deep directory
tree can’t end up recursively removing /usr as a result of
directories being moved up the tree.
rmdir dir ...
Removes empty directories specified.
sync Calls the system call of the same name (see sync(2)), which
flushes dirty buffers to disk. It might return before the I/O
has actually been completed.
THE ZSH/MAPFILE MODULE
The zsh/mapfile module provides one special associative array parame-
ter of the same name.
mapfile
This associative array takes as keys the names of files; the
resulting value is the content of the file. The value is
treated identically to any other text coming from a parameter.
The value may also be assigned to, in which case the file in
question is written (whether or not it originally existed); or
an element may be unset, which will delete the file in ques-
tion. For example, ‘vared mapfile[myfile]’ works as expected,
editing the file ‘myfile’.
When the array is accessed as a whole, the keys are the names
of files in the current directory, and the values are empty (to
save a huge overhead in memory). Thus ${(k)mapfile} has the
same affect as the glob operator *(D), since files beginning
with a dot are not special. Care must be taken with expres-
sions such as rm ${(k)mapfile}, which will delete every file in
the current directory without the usual ‘rm *’ test.
The parameter mapfile may be made read-only; in that case,
files referenced may not be written or deleted.
Limitations
Although reading and writing of the file in question is efficiently
handled, zsh’s internal memory management may be arbitrarily baroque.
Thus it should not automatically be assumed that use of mapfile repre-
sents a gain in efficiency over use of other mechanisms. Note in par-
ticular that the whole contents of the file will always reside physi-
cally in memory when accessed (possibly multiple times, due to stan-
dard parameter substitution operations). In particular, this means
handling of sufficiently long files (greater than the machine’s swap
space, or than the range of the pointer type) will be incorrect.
No errors are printed or flagged for non-existent, unreadable, or
unwritable files, as the parameter mechanism is too low in the shell
execution hierarchy to make this convenient.
It is unfortunate that the mechanism for loading modules does not yet
allow the user to specify the name of the shell parameter to be given
the special behaviour.
THE ZSH/MATHFUNC MODULE
The zsh/mathfunc module provides standard mathematical functions for
use when evaluating mathematical formulae. The syntax agrees with
normal C and FORTRAN conventions, for example,
(( f = sin(0.3) ))
assigns the sine of 0.3 to the parameter f.
Most functions take floating point arguments and return a floating
point value. However, any necessary conversions from or to integer
type will be performed automatically by the shell. Apart from atan
with a second argument and the abs, int and float functions, all func-
tions behave as noted in the manual page for the corresponding C func-
tion, except that any arguments out of range for the function in ques-
tion will be detected by the shell and an error reported.
The following functions take a single floating point argument: acos,
acosh, asin, asinh, atan, atanh, cbrt, ceil, cos, cosh, erf, erfc,
exp, expm1, fabs, floor, gamma, j0, j1, lgamma, log, log10, log1p,
logb, sin, sinh, sqrt, tan, tanh, y0, y1. The atan function can
optionally take a second argument, in which case it behaves like the C
function atan2. The ilogb function takes a single floating point
argument, but returns an integer.
The function signgam takes no arguments, and returns an integer, which
is the C variable of the same name, as described in gamma(3). Note
that it is therefore only useful immediately after a call to gamma or
lgamma. Note also that ‘signgam()’ and ‘signgam’ are distinct expres-
sions.
The following functions take two floating point arguments: copysign,
fmod, hypot, nextafter.
The following take an integer first argument and a floating point sec-
ond argument: jn, yn.
The following take a floating point first argument and an integer sec-
ond argument: ldexp, scalb.
The function abs does not convert the type of its single argument; it
returns the absolute value of either a floating point number or an
integer. The functions float and int convert their arguments into a
floating point or integer value (by truncation) respectively.
Note that the C pow function is available in ordinary math evaluation
as the ‘**’ operator and is not provided here.
The function rand48 is available if your system’s mathematical library
has the function erand48(3). It returns a pseudo-random floating
point number between 0 and 1. It takes a single string optional argu-
ment.
If the argument is not present, the random number seed is initialised
by three calls to the rand(3) function --- this produces the same ran-
dom numbers as the next three values of $RANDOM.
If the argument is present, it gives the name of a scalar parameter
where the current random number seed will be stored. On the first
call, the value must contain at least twelve hexadecimal digits (the
remainder of the string is ignored), or the seed will be initialised
in the same manner as for a call to rand48 with no argument. Subse-
quent calls to rand48(param) will then maintain the seed in the param-
eter param as a string of twelve hexadecimal digits, with no base sig-
nifier. The random number sequences for different parameters are com-
pletely independent, and are also independent from that used by calls
to rand48 with no argument.
For example, consider
print $(( rand48(seed) ))
print $(( rand48() ))
print $(( rand48(seed) ))
Assuming $seed does not exist, it will be initialised by the first
call. In the second call, the default seed is initialised; note, how-
ever, that because of the properties of rand() there is a correlation
between the seeds used for the two initialisations, so for more secure
uses, you should generate your own 12-byte seed. The third call
returns to the same sequence of random numbers used in the first call,
unaffected by the intervening rand48().
THE ZSH/PARAMETER MODULE
The zsh/parameter module gives access to some of the internal hash
tables used by the shell by defining some special parameters.
options
The keys for this associative array are the names of the
options that can be set and unset using the setopt and unsetopt
builtins. The value of each key is either the string on if the
option is currently set, or the string off if the option is
unset. Setting a key to one of these strings is like setting
or unsetting the option, respectively. Unsetting a key in this
array is like setting it to the value off.
commands
This array gives access to the command hash table. The keys are
the names of external commands, the values are the pathnames of
the files that would be executed when the command would be
invoked. Setting a key in this array defines a new entry in
this table in the same way as with the hash builtin. Unsetting
a key as in ‘unset "commands[foo]"’ removes the entry for the
given key from the command hash table.
functions
This associative array maps names of enabled functions to their
definitions. Setting a key in it is like defining a function
with the name given by the key and the body given by the value.
Unsetting a key removes the definition for the function named
by the key.
dis_functions
Like functions but for disabled functions.
builtins
This associative array gives information about the builtin com-
mands currently enabled. The keys are the names of the builtin
commands and the values are either ‘undefined’ for builtin com-
mands that will automatically be loaded from a module if
invoked or ‘defined’ for builtin commands that are already
loaded.
dis_builtins
Like builtins but for disabled builtin commands.
reswords
This array contains the enabled reserved words.
dis_reswords
Like reswords but for disabled reserved words.
aliases
This maps the names of the regular aliases currently enabled to
their expansions.
dis_aliases
Like aliases but for disabled regular aliases.
galiases
Like aliases, but for global aliases.
dis_galiases
Like galiases but for disabled global aliases.
saliases
Like raliases, but for suffix aliases.
dis_saliases
Like saliases but for disabled suffix aliases.
parameters
The keys in this associative array are the names of the parame-
ters currently defined. The values are strings describing the
type of the parameter, in the same format used by the t parame-
ter flag, see zshexpn(1) . Setting or unsetting keys in this
array is not possible.
modules
An associative array giving information about modules. The keys
are the names of the modules loaded, registered to be
autoloaded, or aliased. The value says which state the named
module is in and is one of the strings ‘loaded’, ‘autoloaded’,
or ‘alias:name’, where name is the name the module is aliased
to.
Setting or unsetting keys in this array is not possible.
dirstack
A normal array holding the elements of the directory stack.
Note that the output of the dirs builtin command includes one
more directory, the current working directory.
history
This associative array maps history event numbers to the full
history lines.
historywords
A special array containing the words stored in the history.
jobdirs
This associative array maps job numbers to the directories from
which the job was started (which may not be the current direc-
tory of the job).
jobtexts
This associative array maps job numbers to the texts of the
command lines that were used to start the jobs.
jobstates
This associative array gives information about the states of
the jobs currently known. The keys are the job numbers and the
values are strings of the form ‘job-state:mark:pid=state...’.
The job-state gives the state the whole job is currently in,
one of ‘running’, ‘suspended’, or ‘done’. The mark is ‘+’ for
the current job, ‘-’ for the previous job and empty otherwise.
This is followed by one ‘pid=state’ for every process in the
job. The pids are, of course, the process IDs and the state
describes the state of that process.
nameddirs
This associative array maps the names of named directories to
the pathnames they stand for.
userdirs
This associative array maps user names to the pathnames of
their home directories.
funcstack
This array contains the names of the functions currently being
executed. The first element is the name of the function using
the parameter.
THE ZSH/PCRE MODULE
The zsh/pcre module makes some commands available as builtins:
pcre_compile [ -aimx ] PCRE
Compiles a perl-compatible regular expression.
Option -a will force the pattern to be anchored. Option -i
will compile a case-insensitive pattern. Option -m will com-
pile a multi-line pattern; that is, ^ and $ will match newlines
within the pattern. Option -x will compile an extended pat-
tern, wherein whitespace and # comments are ignored.
pcre_study
Studies the previously-compiled PCRE which may result in faster
matching.
pcre_match [ -a arr ] string
Returns successfully if string matches the previously-compiled
PCRE.
If the expression captures substrings within parentheses,
pcre_match will set the array $match to those substrings,
unless the -a option is given, in which case it will set the
array arr.
THE ZSH/SCHED MODULE
The zsh/sched module makes available one builtin command:
sched [+]hh:mm command ...
sched [ -item ]
Make an entry in the scheduled list of commands to execute.
The time may be specified in either absolute or relative time.
With no arguments, prints the list of scheduled commands. With
the argument ‘-item’, removes the given item from the list.
THE ZSH/NET/SOCKET MODULE
The zsh/net/socket module makes available one builtin command:
zsocket [ -altv ] [ -d fd ] [ args ]
zsocket is implemented as a builtin to allow full use of shell
command line editing, file I/O, and job control mechanisms.
Outbound Connections
zsocket [ -v ] [ -d fd ] filename
Open a new Unix domain connection to filename. The shell
parameter REPLY will be set to the file descriptor associated
with that connection. Currently, only stream connections are
supported.
If -d is specified, its argument will be taken as the target
file descriptor for the connection.
In order to elicit more verbose output, use -v.
Inbound Connections
zsocket -l [ -v ] [ -d fd ] filename
zsocket -l will open a socket listening on filename. The shell
parameter REPLY will be set to the file descriptor associated
with that listener.
If -d is specified, its argument will be taken as the target
file descriptor for the connection.
In order to elicit more verbose output, use -v.
zsocket -a [ -tv ] [ -d targetfd ] listenfd
zsocket -a will accept an incoming connection to the socket
associated with listenfd. The shell parameter REPLY will be
set to the file descriptor associated with the inbound connec-
tion.
If -d is specified, its argument will be taken as the target
file descriptor for the connection.
If -t is specified, zsocket will return if no incoming connec-
tion is pending. Otherwise it will wait for one.
In order to elicit more verbose output, use -v.
THE ZSH/STAT MODULE
The zsh/stat module makes available one builtin command:
stat [ -gnNolLtTrs ] [ -f fd ] [ -H hash ] [ -A array ] [ -F fmt ] [
+element ] [ file ... ]
The command acts as a front end to the stat system call (see
stat(2)). If the stat call fails, the appropriate system error
message printed and status 1 is returned. The fields of struct
stat give information about the files provided as arguments to
the command. In addition to those available from the stat
call, an extra element ‘link’ is provided. These elements are:
device The number of the device on which the file resides.
inode The unique number of the file on this device (‘inode’
number).
mode The mode of the file; that is, the file’s type and
access permissions. With the -s option, this will be
returned as a string corresponding to the first column
in the display of the ls -l command.
nlink The number of hard links to the file.
uid The user ID of the owner of the file. With the -s
option, this is displayed as a user name.
gid The group ID of the file. With the -s option, this is
displayed as a group name.
rdev The raw device number. This is only useful for special
devices.
size The size of the file in bytes.
atime
mtime
ctime The last access, modification and inode change times of
the file, respectively, as the number of seconds since
midnight GMT on 1st January, 1970. With the -s option,
these are printed as strings for the local time zone;
the format can be altered with the -F option, and with
the -g option the times are in GMT.
blksize
The number of bytes in one allocation block on the
device on which the file resides.
block The number of disk blocks used by the file.
link If the file is a link and the -L option is in effect,
this contains the name of the file linked to, otherwise
it is empty. Note that if this element is selected
(‘‘stat +link’’) then the -L option is automatically
used.
A particular element may be selected by including its name pre-
ceded by a ‘+’ in the option list; only one element is allowed.
The element may be shortened to any unique set of leading char-
acters. Otherwise, all elements will be shown for all files.
Options:
-A array
Instead of displaying the results on standard output,
assign them to an array, one struct stat element per
array element for each file in order. In this case nei-
ther the name of the element nor the name of the files
appears in array unless the -t or -n options were given,
respectively. If -t is given, the element name appears
as a prefix to the appropriate array element; if -n is
given, the file name appears as a separate array element
preceding all the others. Other formatting options are
respected.
-H hash
Similar to -A, but instead assign the values to hash.
The keys are the elements listed above. If the -n
option is provided then the name of the file is included
in the hash with key name.
-f fd Use the file on file descriptor fd instead of named
files; no list of file names is allowed in this case.
-F fmt Supplies a strftime (see strftime(3)) string for the
formatting of the time elements. The -s option is
implied.
-g Show the time elements in the GMT time zone. The -s
option is implied.
-l List the names of the type elements (to standard output
or an array as appropriate) and return immediately;
options other than -A and arguments are ignored.
-L Perform an lstat (see lstat(2)) rather than a stat sys-
tem call. In this case, if the file is a link, informa-
tion about the link itself rather than the target file
is returned. This option is required to make the link
element useful.
-n Always show the names of files. Usually these are only
shown when output is to standard output and there is
more than one file in the list.
-N Never show the names of files.
-o If a raw file mode is printed, show it in octal, which
is more useful for human consumption than the default of
decimal. A leading zero will be printed in this case.
Note that this does not affect whether a raw or format-
ted file mode is shown, which is controlled by the -r
and -s options, nor whether a mode is shown at all.
-r Print raw data (the default format) alongside string
data (the -s format); the string data appears in paren-
theses after the raw data.
-s Print mode, uid, gid and the three time elements as
strings instead of numbers. In each case the format is
like that of ls -l.
-t Always show the type names for the elements of struct
stat. Usually these are only shown when output is to
standard output and no individual element has been
selected.
-T Never show the type names of the struct stat elements.
THE ZSH/SYSTEM MODULE
The zsh/system module makes available three builtin commands and a
parameter.
BUILTINS
syserror [ -e errvar ] [ -p prefix ] [ errno | errname ]
This command prints out the error message associated with
errno, a system error number, followed by a newline to standard
error.
Instead of the error number, a name errname, for example
ENOENT, may be used. The set of names is the same as the con-
tents of the array errnos, see below.
If the string prefix is given, it is printed in front of the
error message, with no intervening space.
If errvar is supplied, the entire message, without a newline,
is assigned to the parameter names errvar and nothing is out-
put.
A return value of 0 indicates the message was successfully
printed (although it may not be useful if the error number was
out of the system’s range), a return value of 1 indicates an
error in the parameters, and a return value of 2 indicates the
error name was not recognised (no message is printed for this).
sysread [ -c countvar ] [ -i infd ] [ -o outfd ]
[ -s bufsize ] [ -t timeout ] [ param ]
Perform a single system read from file descriptor infd, or zero
if that is not given. The result of the read is stored in
param or REPLY if that is not given. If countvar is given, the
number of bytes read is assigned to the parameter named by
countvar.
The maximum number of bytes read is bufsize or 8192 if that is
not given, however the command returns as soon as any number of
bytes was successfully read.
If timeout is given, it specifies a timeout in seconds, which
may be zero to poll the file descriptor. This is handled by
the poll system call if available, otherwise the select system
call if available.
If outfd is given, an attempt is made to write all the bytes
just read to the file descriptor outfd. If this fails, because
of a system error other than EINTR or because of an internal
zsh error during an interrupt, the bytes read but not written
are stored in the parameter named by param if supplied (no
default is used in this case), and the number of bytes read but
not written is stored in the parameter named by countvar if
that is supplied. If it was successful, countvar contains the
full number of bytes transferred, as usual, and param is not
set.
The error EINTR (interrupted system call) is handled internally
so that shell interrupts are transparent to the caller. Any
other error causes a return.
The possible return values are
0 At least one byte of data was successfully read and, if
appropriate, written.
1 There was an error in the parameters to the command.
This is the only error for which a message is printed to
standard error.
2 There was an error on the read, or on polling the input
file descriptor for a timeout. The parameter ERRNO
gives the error.
3 Data were successfully read, but there was an error
writing them to outfd. The parameter ERRNO gives the
error.
4 The attempt to read timed out. Note this does not set
ERRNO as this is not a system error.
5 No system error occurred, but zero bytes were read.
This usually indicates end of file. The parameters are
set according to the usual rules; no write to outfd is
attempted.
syswrite [ -c countvar ] [ -o outfd ] data
The data (a single string of bytes) are written to the file
descriptor outfd, or 1 if that is not given, using the write
system call. Multiple write operations may be used if the
first does not write all the data.
If countvar is given, the number of byte written is stored in
the parameter named by countvar; this may not be the full
length of data if an error occurred.
The error EINTR (interrupted system call) is handled internally
by retrying; otherwise an error causes the command to return.
For example, if the file descriptor is set to non-blocking out-
put, an error EAGAIN (on some systems, EWOULDBLOCK) may result
in the command returning early.
The return status may be 0 for success, 1 for an error in the
parameters to the command, or 2 for an error on the write; no
error message is printed in the last case, but the parameter
ERRNO will reflect the error that occurred.
PARAMETERS
errnos A readonly array of the names of errors defined on the system.
These are typically macros defined in C by including the system
header file errno.h. The index of each name (assuming the
option KSH_ARRAYS is unset) corresponds to the error number.
Error numbers num before the last known error which have no
name are given the name Enum in the array.
Note that aliases for errors are not handled; only the canoni-
cal name is used.
THE ZSH/NET/TCP MODULE
The zsh/net/tcp module makes available one builtin command:
ztcp [ -acflLtv ] [ -d fd ] [ args ]
ztcp is implemented as a builtin to allow full use of shell
command line editing, file I/O, and job control mechanisms.
If ztcp is run with no options, it will output the contents of
its session table.
If it is run with only the option -L, it will output the con-
tents of the session table in a format suitable for automatic
parsing. The option is ignored if given with a command to open
or close a session. The output consists of a set of lines, one
per session, each containing the following elements separated
by spaces:
File descriptor
The file descriptor in use for the connection. For nor-
mal inbound (I) and outbound (O) connections this may be
read and written by the usual shell mechanisms. How-
ever, it should only be close with ‘ztcp -c’.
Connection type
A letter indicating how the session was created:
Z A session created with the zftp command.
L A connection opened for listening with ‘ztcp
-l’.
I An inbound connection accepted with ‘ztcp -a’.
O An outbound connection created with ‘ztcp host
...’.
The local host
This is usually set to an all-zero IP address as the
address of the localhost is irrelevant.
The local port
This is likely to be zero unless the connection is for
listening.
The remote host
This is the fully qualified domain name of the peer, if
available, else an IP address. It is an all-zero IP
address for a session opened for listening.
The remote port
This is zero for a connection opened for listening.
Outbound Connections
ztcp [ -v ] [ -d fd ] host [ port ]
Open a new TCP connection to host. If the port is omitted, it
will default to port 23. The connection will be added to the
session table and the shell parameter REPLY will be set to the
file descriptor associated with that connection.
If -d is specified, its argument will be taken as the target
file descriptor for the connection.
In order to elicit more verbose output, use -v.
Inbound Connections
ztcp -l [ -v ] [ -d fd ] port
ztcp -l will open a socket listening on TCP port. The socket
will be added to the session table and the shell parameter
REPLY will be set to the file descriptor associated with that
listener.
If -d is specified, its argument will be taken as the target
file descriptor for the connection.
In order to elicit more verbose output, use -v.
ztcp -a [ -tv ] [ -d targetfd ] listenfd
ztcp -a will accept an incoming connection to the port associ-
ated with listenfd. The connection will be added to the ses-
sion table and the shell parameter REPLY will be set to the
file descriptor associated with the inbound connection.
If -d is specified, its argument will be taken as the target
file descriptor for the connection.
If -t is specified, ztcp will return if no incoming connection
is pending. Otherwise it will wait for one.
In order to elicit more verbose output, use -v.
Closing Connections
ztcp -cf [ -v ] [ fd ]
ztcp -c [ -v ] [ fd ]
ztcp -c will close the socket associated with fd. The socket
will be removed from the session table. If fd is not speci-
fied, ztcp will close everything in the session table.
Normally, sockets registered by zftp (see zshmodules(1) ) can-
not be closed this way. In order to force such a socket
closed, use -f.
In order to elicit more verbose output, use -v.
Example
Here is how to create a TCP connection between two instances of zsh.
We need to pick an unassigned port; here we use the randomly chosen
5123.
On host1,
zmodload zsh/net/tcp
ztcp -l 5123
listenfd=$REPLY
ztcp -a $listenfd
fd=$REPLY
The second from last command blocks until there is an incoming connec-
tion.
Now create a connection from host2 (which may, of course, be the same
machine):
zmodload zsh/net/tcp
ztcp host1 5123
fd=$REPLY
Now on each host, $fd contains a file descriptor for talking to the
other. For example, on host1:
print This is a message >&$fd
and on host2:
read -r line <&$fd; print -r - $line
prints ‘This is a message’.
To tidy up, on host1:
ztcp -c $listenfd
ztcp -c $fd
and on host2
ztcp -c $fd
THE ZSH/TERMCAP MODULE
The zsh/termcap module makes available one builtin command:
echotc cap [ arg ... ]
Output the termcap value corresponding to the capability cap,
with optional arguments.
The zsh/termcap module makes available one parameter:
termcap
An associative array that maps termcap capability codes to
their values.
THE ZSH/TERMINFO MODULE
The zsh/terminfo module makes available one builtin command:
echoti cap [ arg ]
Output the terminfo value corresponding to the capability cap,
instantiated with arg if applicable.
The zsh/terminfo module makes available one parameter:
terminfo
An associative array that maps terminfo capability names to
their values.
THE ZSH/ZFTP MODULE
The zsh/zftp module makes available one builtin command:
zftp subcommand [ args ]
The zsh/zftp module is a client for FTP (file transfer proto-
col). It is implemented as a builtin to allow full use of
shell command line editing, file I/O, and job control mecha-
nisms. Often, users will access it via shell functions provid-
ing a more powerful interface; a set is provided with the zsh
distribution and is described in zshzftpsys(1). However, the
zftp command is entirely usable in its own right.
All commands consist of the command name zftp followed by the
name of a subcommand. These are listed below. The return sta-
tus of each subcommand is supposed to reflect the success or
failure of the remote operation. See a description of the
variable ZFTP_VERBOSE for more information on how responses
from the server may be printed.
Subcommands
open host [ user [ password [ account ] ] ]
Open a new FTP session to host, which may be the name of a
TCP/IP connected host or an IP number in the standard dot nota-
tion. Remaining arguments are passed to the login subcommand.
Note that if no arguments beyond host are supplied, open will
not automatically call login. If no arguments at all are sup-
plied, open will use the parameters set by the params subcom-
mand.
After a successful open, the shell variables ZFTP_HOST, ZFTP_IP
and ZFTP_SYSTEM are available; see ‘Variables’ below.
login [ name [ password [ account ] ] ]
user [ name [ password [ account ] ] ]
Login the user name with parameters password and account. Any
of the parameters can be omitted, and will be read from stan-
dard input if needed (name is always needed). If standard
input is a terminal, a prompt for each one will be printed on
standard error and password will not be echoed. If any of the
parameters are not used, a warning message is printed.
After a successful login, the shell variables ZFTP_USER,
ZFTP_ACCOUNT and ZFTP_PWD are available; see ‘Variables’ below.
This command may be re-issued when a user is already logged in,
and the server will first be reinitialized for a new user.
params [ host [ user [ password [ account ] ] ] ]
params -
Store the given parameters for a later open command with no
arguments. Only those given on the command line will be remem-
bered. If no arguments are given, the parameters currently set
are printed, although the password will appear as a line of
stars; the return value is one if no parameters were set, zero
otherwise.
Any of the parameters may be specified as a ‘?’, which may need
to be quoted to protect it from shell expansion. In this case,
the appropriate parameter will be read from stdin as with the
login subcommand, including special handling of password. If
the ‘?’ is followed by a string, that is used as the prompt for
reading the parameter instead of the default message (any nec-
essary punctuation and whitespace should be included at the end
of the prompt). The first letter of the parameter (only) may
be quoted with a ‘\’; hence an argument "\\$word" guarantees
that the string from the shell parameter $word will be treated
literally, whether or not it begins with a ‘?’.
If instead a single ‘-’ is given, the existing parameters, if
any, are deleted. In that case, calling open with no arguments
will cause an error.
The list of parameters is not deleted after a close, however it
will be deleted if the zsh/zftp module is unloaded.
For example,
zftp params ftp.elsewhere.xx juser ’?Password for juser: ’
will store the host ftp.elsewhere.xx and the user juser and
then prompt the user for the corresponding password with the
given prompt.
test Test the connection; if the server has reported that it has
closed the connection (maybe due to a timeout), return status
2; if no connection was open anyway, return status 1; else
return status 0. The test subcommand is silent, apart from
messages printed by the $ZFTP_VERBOSE mechanism, or error mes-
sages if the connection closes. There is no network overhead
for this test.
The test is only supported on systems with either the select(2)
or poll(2) system calls; otherwise the message ‘not supported
on this system’ is printed instead.
The test subcommand will automatically be called at the start
of any other subcommand for the current session when a connec-
tion is open.
cd directory
Change the remote directory to directory. Also alters the
shell variable ZFTP_PWD.
cdup Change the remote directory to the one higher in the directory
tree. Note that cd .. will also work correctly on non-UNIX
systems.
dir [ args... ]
Give a (verbose) listing of the remote directory. The args are
passed directly to the server. The command’s behaviour is
implementation dependent, but a UNIX server will typically
interpret args as arguments to the ls command and with no argu-
ments return the result of ‘ls -l’. The directory is listed to
standard output.
ls [ args ]
Give a (short) listing of the remote directory. With no args,
produces a raw list of the files in the directory, one per
line. Otherwise, up to vagaries of the server implementation,
behaves similar to dir.
type [ type ]
Change the type for the transfer to type, or print the current
type if type is absent. The allowed values are ‘A’ (ASCII),
‘I’ (Image, i.e. binary), or ‘B’ (a synonym for ‘I’).
The FTP default for a transfer is ASCII. However, if zftp
finds that the remote host is a UNIX machine with 8-bit byes,
it will automatically switch to using binary for file transfers
upon open. This can subsequently be overridden.
The transfer type is only passed to the remote host when a data
connection is established; this command involves no network
overhead.
ascii The same as type A.
binary The same as type I.
mode [ S | B ]
Set the mode type to stream (S) or block (B). Stream mode is
the default; block mode is not widely supported.
remote files...
local [ files... ]
Print the size and last modification time of the remote or
local files. If there is more than one item on the list, the
name of the file is printed first. The first number is the
file size, the second is the last modification time of the file
in the format CCYYMMDDhhmmSS consisting of year, month, date,
hour, minutes and seconds in GMT. Note that this format,
including the length, is guaranteed, so that time strings can
be directly compared via the [[ builtin’s < and > operators,
even if they are too long to be represented as integers.
Not all servers support the commands for retrieving this infor-
mation. In that case, the remote command will print nothing
and return status 2, compared with status 1 for a file not
found.
The local command (but not remote) may be used with no argu-
ments, in which case the information comes from examining file
descriptor zero. This is the same file as seen by a put com-
mand with no further redirection.
get file [...]
Retrieve all files from the server, concatenating them and
sending them to standard output.
put file [...]
For each file, read a file from standard input and send that to
the remote host with the given name.
append file [...]
As put, but if the remote file already exists, data is appended
to it instead of overwriting it.
getat file point
putat file point
appendat file point
Versions of get, put and append which will start the transfer
at the given point in the remote file. This is useful for
appending to an incomplete local file. However, note that this
ability is not universally supported by servers (and is not
quite the behaviour specified by the standard).
delete file [...]
Delete the list of files on the server.
mkdir directory
Create a new directory directory on the server.
rmdir directory
Delete the directory directory on the server.
rename old-name new-name
Rename file old-name to new-name on the server.
site args...
Send a host-specific command to the server. You will probably
only need this if instructed by the server to use it.
quote args...
Send the raw FTP command sequence to the server. You should be
familiar with the FTP command set as defined in RFC959 before
doing this. Useful commands may include STAT and HELP. Note
also the mechanism for returning messages as described for the
variable ZFTP_VERBOSE below, in particular that all messages
from the control connection are sent to standard error.
close
quit Close the current data connection. This unsets the shell
parameters ZFTP_HOST, ZFTP_IP, ZFTP_SYSTEM, ZFTP_USER,
ZFTP_ACCOUNT, ZFTP_PWD, ZFTP_TYPE and ZFTP_MODE.
session [ sessname ]
Allows multiple FTP sessions to be used at once. The name of
the session is an arbitrary string of characters; the default
session is called ‘default’. If this command is called without
an argument, it will list all the current sessions; with an
argument, it will either switch to the existing session called
sessname, or create a new session of that name.
Each session remembers the status of the connection, the set of
connection-specific shell parameters (the same set as are unset
when a connection closes, as given in the description of
close), and any user parameters specified with the params sub-
command. Changing to a previous session restores those values;
changing to a new session initialises them in the same way as
if zftp had just been loaded. The name of the current session
is given by the parameter ZFTP_SESSION.
rmsession [ sessname ]
Delete a session; if a name is not given, the current session
is deleted. If the current session is deleted, the earliest
existing session becomes the new current session, otherwise the
current session is not changed. If the session being deleted
is the only one, a new session called ‘default’ is created and
becomes the current session; note that this is a new session
even if the session being deleted is also called ‘default’. It
is recommended that sessions not be deleted while background
commands which use zftp are still active.
Parameters
The following shell parameters are used by zftp. Currently none of
them are special.
ZFTP_TMOUT
Integer. The time in seconds to wait for a network operation
to complete before returning an error. If this is not set when
the module is loaded, it will be given the default value 60. A
value of zero turns off timeouts. If a timeout occurs on the
control connection it will be closed. Use a larger value if
this occurs too frequently.
ZFTP_IP
Readonly. The IP address of the current connection in dot
notation.
ZFTP_HOST
Readonly. The hostname of the current remote server. If the
host was opened as an IP number, ZFTP_HOST contains that
instead; this saves the overhead for a name lookup, as IP num-
bers are most commonly used when a nameserver is unavailable.
ZFTP_SYSTEM
Readonly. The system type string returned by the server in
response to an FTP SYST request. The most interesting case is
a string beginning "UNIX Type: L8", which ensures maximum com-
patibility with a local UNIX host.
ZFTP_TYPE
Readonly. The type to be used for data transfers , either ‘A’
or ‘I’. Use the type subcommand to change this.
ZFTP_USER
Readonly. The username currently logged in, if any.
ZFTP_ACCOUNT
Readonly. The account name of the current user, if any. Most
servers do not require an account name.
ZFTP_PWD
Readonly. The current directory on the server.
ZFTP_CODE
Readonly. The three digit code of the last FTP reply from the
server as a string. This can still be read after the connec-
tion is closed, and is not changed when the current session
changes.
ZFTP_REPLY
Readonly. The last line of the last reply sent by the server.
This can still be read after the connection is closed, and is
not changed when the current session changes.
ZFTP_SESSION
Readonly. The name of the current FTP session; see the
description of the session subcommand.
ZFTP_PREFS
A string of preferences for altering aspects of zftp’s
behaviour. Each preference is a single character. The follow-
ing are defined:
P Passive: attempt to make the remote server initiate
data transfers. This is slightly more efficient than
sendport mode. If the letter S occurs later in the
string, zftp will use sendport mode if passive mode is
not available.
S Sendport: initiate transfers by the FTP PORT command.
If this occurs before any P in the string, passive mode
will never be attempted.
D Dumb: use only the bare minimum of FTP commands. This
prevents the variables ZFTP_SYSTEM and ZFTP_PWD from
being set, and will mean all connections default to
ASCII type. It may prevent ZFTP_SIZE from being set
during a transfer if the server does not send it anyway
(many servers do).
If ZFTP_PREFS is not set when zftp is loaded, it will be set to
a default of ‘PS’, i.e. use passive mode if available, other-
wise fall back to sendport mode.
ZFTP_VERBOSE
A string of digits between 0 and 5 inclusive, specifying which
responses from the server should be printed. All responses go
to standard error. If any of the numbers 1 to 5 appear in the
string, raw responses from the server with reply codes begin-
ning with that digit will be printed to standard error. The
first digit of the three digit reply code is defined by RFC959
to correspond to:
1. A positive preliminary reply.
2. A positive completion reply.
3. A positive intermediate reply.
4. A transient negative completion reply.
5. A permanent negative completion reply.
It should be noted that, for unknown reasons, the reply ‘Ser-
vice not available’, which forces termination of a connection,
is classified as 421, i.e. ‘transient negative’, an interesting
interpretation of the word ‘transient’.
The code 0 is special: it indicates that all but the last line
of multiline replies read from the server will be printed to
standard error in a processed format. By convention, servers
use this mechanism for sending information for the user to
read. The appropriate reply code, if it matches the same
response, takes priority.
If ZFTP_VERBOSE is not set when zftp is loaded, it will be set
to the default value 450, i.e., messages destined for the user
and all errors will be printed. A null string is valid and
specifies that no messages should be printed.
Functions
zftp_chpwd
If this function is set by the user, it is called every time
the directory changes on the server, including when a user is
logged in, or when a connection is closed. In the last case,
$ZFTP_PWD will be unset; otherwise it will reflect the new
directory.
zftp_progress
If this function is set by the user, it will be called during a
get, put or append operation each time sufficient data has been
received from the host. During a get, the data is sent to
standard output, so it is vital that this function should write
to standard error or directly to the terminal, not to standard
output.
When it is called with a transfer in progress, the following
additional shell parameters are set:
ZFTP_FILE
The name of the remote file being transferred from or
to.
ZFTP_TRANSFER
A G for a get operation and a P for a put operation.
ZFTP_SIZE
The total size of the complete file being transferred:
the same as the first value provided by the remote and
local subcommands for a particular file. If the server
cannot supply this value for a remote file being
retrieved, it will not be set. If input is from a pipe
the value may be incorrect and correspond simply to a
full pipe buffer.
ZFTP_COUNT
The amount of data so far transferred; a number between
zero and $ZFTP_SIZE, if that is set. This number is
always available.
The function is initially called with ZFTP_TRANSFER set appro-
priately and ZFTP_COUNT set to zero. After the transfer is
finished, the function will be called one more time with
ZFTP_TRANSFER set to GF or PF, in case it wishes to tidy up.
It is otherwise never called twice with the same value of
ZFTP_COUNT.
Sometimes the progress meter may cause disruption. It is up to
the user to decide whether the function should be defined and
to use unfunction when necessary.
Problems
A connection may not be opened in the left hand side of a pipe as this
occurs in a subshell and the file information is not updated in the
main shell. In the case of type or mode changes or closing the con-
nection in a subshell, the information is returned but variables are
not updated until the next call to zftp. Other status changes in sub-
shells will not be reflected by changes to the variables (but should
be otherwise harmless).
Deleting sessions while a zftp command is active in the background can
have unexpected effects, even if it does not use the session being
deleted. This is because all shell subprocesses share information on
the state of all connections, and deleting a session changes the
ordering of that information.
On some operating systems, the control connection is not valid after a
fork(), so that operations in subshells, on the left hand side of a
pipeline, or in the background are not possible, as they should be.
This is presumably a bug in the operating system.
THE ZSH/ZLE MODULE
The zsh/zle module contains the Zsh Line Editor. See zshzle(1).
THE ZSH/ZLEPARAMETER MODULE
The zsh/zleparameter module defines two special parameters that can be
used to access internal information of the Zsh Line Editor (see zsh-
zle(1)).
keymaps
This array contains the names of the keymaps currently defined.
widgets
This associative array contains one entry per widget defined.
The name of the widget is the key and the value gives informa-
tion about the widget. It is either the string ‘builtin’ for
builtin widgets, a string of the form ‘user:name’ for
user-defined widgets, where name is the name of the shell func-
tion implementing the widget, or it is a string of the form
‘completion:type:name’, for completion widgets. In the last
case type is the name of the builtin widgets the completion
widget imitates in its behavior and name is the name of the
shell function implementing the completion widget.
THE ZSH/ZPROF MODULE
When loaded, the zsh/zprof causes shell functions to be profiled. The
profiling results can be obtained with the zprof builtin command made
available by this module. There is no way to turn profiling off other
than unloading the module.
zprof [ -c ]
Without the -c option, zprof lists profiling results to stan-
dard output. The format is comparable to that of commands like
gprof.
At the top there is a summary listing all functions that were
called at least once. This summary is sorted in decreasing
order of the amount of time spent in each. The lines contain
the number of the function in order, which is used in other
parts of the list in suffixes of the form ‘[num]’.RE, then the
number of calls made to the function. The next three columns
list the time in milliseconds spent in the function and its
descendents, the average time in milliseconds spent in the
function and its descendents per call and the percentage of
time spent in all shell functions used in this function and its
descendents. The following three columns give the same infor-
mation, but counting only the time spent in the function
itself. The final column shows the name of the function.
After the summary, detailed information about every function
that was invoked is listed, sorted in decreasing order of the
amount of time spent in each function and its descendents.
Each of these entries consists of descriptions for the func-
tions that called the function described, the function itself,
and the functions that were called from it. The description
for the function itself has the same format as in the summary
(and shows the same information). The other lines don’t show
the number of the function at the beginning and have their
function named indented to make it easier to distinguish the
line showing the function described in the section from the
surrounding lines.
The information shown in this case is almost the same as in the
summary, but only refers to the call hierarchy being displayed.
For example, for a calling function the column showing the
total running time lists the time spent in the described func-
tion and its descendents only for the times when it was called
from that particular calling function. Likewise, for a called
function, this columns lists the total time spent in the called
function and its descendents only for the times when it was
called from the function described.
Also in this case, the column showing the number of calls to a
function also shows a slash and then the total number of invo-
cations made to the called function.
As long as the zsh/zprof module is loaded, profiling will be
done and multiple invocations of the zprof builtin command will
show the times and numbers of calls since the module was
loaded. With the -c option, the zprof builtin command will
reset its internal counters and will not show the listing. )
THE ZSH/ZPTY MODULE
The zsh/zpty module offers one builtin:
zpty [ -e ] [ -b ] name [ arg ... ]
The arguments following name are concatenated with spaces
between, then executed as a command, as if passed to the eval
builtin. The command runs under a newly assigned pseudo-termi-
nal; this is useful for running commands non-interactively
which expect an interactive environment. The name is not part
of the command, but is used to refer to this command in later
calls to zpty.
With the -e option, the pseudo-terminal is set up so that input
characters are echoed.
With the -b option, input to and output from the pseudo-termi-
nal are made non-blocking.
zpty -d [ names ... ]
The second form, with the -d option, is used to delete commands
previously started, by supplying a list of their names. If no
names are given, all commands are deleted. Deleting a command
causes the HUP signal to be sent to the corresponding process.
zpty -w [ -n ] name [ strings ... ]
The -w option can be used to send the to command name the given
strings as input (separated by spaces). If the -n option is
not given, a newline is added at the end.
If no strings are provided, the standard input is copied to the
pseudo-terminal; this may stop before copying the full input if
the pseudo-terminal is non-blocking.
Note that the command under the pseudo-terminal sees this input
as if it were typed, so beware when sending special tty driver
characters such as word-erase, line-kill, and end-of-file.
zpty -r [ -t ] name [ param [ pattern ] ]
The -r option can be used to read the output of the command
name. With only a name argument, the output read is copied to
the standard output. Unless the pseudo-terminal is non-block-
ing, copying continues until the command under the pseudo-ter-
minal exits; when non-blocking, only as much output as is imme-
diately available is copied. The return value is zero if any
output is copied.
When also given a param argument, at most one line is read and
stored in the parameter named param. Less than a full line may
be read if the pseudo-terminal is non-blocking. The return
value is zero if at least one character is stored in param.
If a pattern is given as well, output is read until the whole
string read matches the pattern, even in the non-blocking case.
The return value is zero if the string read matches the pat-
tern, or if the command has exited but at least one character
could still be read. As of this writing, a maximum of one
megabyte of output can be consumed this way; if a full megabyte
is read without matching the pattern, the return value is
non-zero.
In all cases, the return value is non-zero if nothing could be
read, and is 2 if this is because the command has finished.
If the -r option is combined with the -t option, zpty tests
whether output is available before trying to read. If no out-
put is available, zpty immediately returns the value 1.
zpty -t name
The -t option without the -r option can be used to test whether
the command name is still running. It returns a zero value if
the command is running and a non-zero value otherwise.
zpty [ -L ]
The last form, without any arguments, is used to list the com-
mands currently defined. If the -L option is given, this is
done in the form of calls to the zpty builtin.
THE ZSH/ZSELECT MODULE
The zsh/zselect module makes available one builtin command:
zselect [ -rwe -t timeout -a array ] [ fd ... ]
The zselect builtin is a front-end to the ‘select’ system call,
which blocks until a file descriptor is ready for reading or
writing, or has an error condition, with an optional timeout.
If this is not available on your system, the command prints an
error message and returns status 2 (normal errors return status
1). For more information, see your systems documentation for
select(3). Note there is no connection with the shell builtin
of the same name.
Arguments and options may be intermingled in any order.
Non-option arguments are file descriptors, which must be deci-
mal integers. By default, file descriptors are to be tested
for reading, i.e. zselect will return when data is available to
be read from the file descriptor, or more precisely, when a
read operation from the file descriptor will not block. After
a -r, -w and -e, the given file descriptors are to be tested
for reading, writing, or error conditions. These options and
an arbitrary list of file descriptors may be given in any
order.
(The presence of an ‘error condition’ is not well defined in
the documentation for many implementations of the select system
call. According to recent versions of the POSIX specification,
it is really an exception condition, of which the only standard
example is out-of-band data received on a socket. So zsh users
are unlikely to find the -e option useful.)
The option ‘-t timeout’ specifies a timeout in hundredths of a
second. This may be zero, in which case the file descriptors
will simply be polled and zselect will return immediately. It
is possible to call zselect with no file descriptors and a
non-zero timeout for use as a finer-grained replacement for
‘sleep’; not, however, the return status is always 1 for a
timeout.
The option ‘-a array’ indicates that array should be set to
indicate the file descriptor(s) which are ready. If the option
is not given, the array reply will be used for this purpose.
The array will contain a string similar to the arguments for
zselect. For example,
zselect -t 0 -r 0 -w 1
might return immediately with status 0 and $reply containing
‘-r 0 -w 1’ to show that both file descriptors are ready for
the requested operations.
The option ‘-A assoc’ indicates that the associative array
assoc should be set to indicate the file descriptor(s) which
are ready. This option overrides the option -a, nor will reply
be modified. The keys of assoc are the file descriptors, and
the corresponding values are any of the characters ‘rwe’ to
indicate the condition.
The command returns 0 if some file descriptors are ready for
reading. If the operation timed out, or a timeout of 0 was
given and no file descriptors were ready, or there was an
error, it returns status 1 and the array will not be set (nor
modified in any way). If there was an error in the select
operation the appropriate error message is printed.
THE ZSH/ZUTIL MODULE
The zsh/zutil module only adds some builtins:
zstyle [ -L ]
zstyle [ -e | - | -- ] pattern style strings ...
zstyle -d [ pattern [ styles ... ] ]
zstyle -g name [ pattern [ style ] ]
zstyle -abs context style name [ sep ]
zstyle -Tt context style [ strings ...]
zstyle -m context style pattern
This builtin command is used to define and lookup styles.
Styles are pairs of names and values, where the values consist
of any number of strings. They are stored together with pat-
terns and lookup is done by giving a string, called the ‘con-
text’, which is compared to the patterns. The definition
stored for the first matching pattern will be returned.
For ordering of comparisons, patterns are searched from most
specific to least specific, and patterns that are equally spe-
cific keep the order in which they were defined. A pattern is
considered to be more specific than another if it contains more
components (substrings separated by colons) or if the patterns
for the components are more specific, where simple strings are
considered to be more specific than patterns and complex pat-
terns are considered to be more specific than the pattern ‘*’.
The first form (without arguments) lists the definitions in the
order zstyle will test them. If the -L option is given, listing
is done in the form of calls to zstyle. Forms with arguments:
zstyle [ - | -- | -e ] pattern style strings ...
Defines the given style for the pattern with the strings
as the value. If the -e option is given, the strings
will be concatenated (separated by spaces) and the
resulting string will be evaluated (in the same way as
it is done by the eval builtin command) when the style
is looked up. In this case the parameter ‘reply’ must
be assigned to set the strings returned after the evalu-
ation. Before evaluating the value, reply is unset, and
if it is still unset after the evaluation, the style is
treated as if it were not set.
zstyle -d [ pattern [ styles ... ] ]
Delete style definitions. Without arguments all defini-
tions are deleted, with a pattern all definitions for
that pattern are deleted and if any styles are given,
then only those styles are deleted for the pattern.
zstyle -g name [ pattern [ style ] ]
Retrieve a style definition. The name is used as the
name of an array in which the results are stored. With-
out any further arguments, all patterns defined are
returned. With a pattern the styles defined for that
pattern are returned and with both a pattern and a
style, the value strings of that combination is
returned.
The other forms can be used to look up or test patterns.
zstyle -s context style name [ sep ]
The parameter name is set to the value of the style
interpreted as a string. If the value contains several
strings they are concatenated with spaces (or with the
sep string if that is given) between them.
zstyle -b context style name
The value is stored in name as a boolean, i.e. as the
string ‘yes’ if the value has only one string and that
string is equal to one of ‘yes’, ‘true’, ‘on’, or ‘1’.
If the value is any other string or has more than one
string, the parameter is set to ‘no’.
zstyle -a context style name
The value is stored in name as an array. If name is
declared as an associative array, the first, third,
etc. strings are used as the keys and the other strings
are used as the values.
zstyle -t context style [ strings ...]
zstyle -T context style [ strings ...]
Test the value of a style, i.e. the -t option only
returns a status (sets $?). Without any strings the
return status is zero if the style is defined for at
least one matching pattern, has only one string in its
value, and that is equal to one of ‘true’, ‘yes’, ‘on’
or ‘1’. If any strings are given the status is zero if
and only if at least one of the strings is equal to at
least one of the strings in the value. If the style is
not defined, the status is 2.
The -T option tests the values of the style like -t, but
it returns zero (rather than 2) if the style is not
defined for any matching pattern.
zstyle -m context style pattern
Match a value. Returns status zero if the pattern
matches at least one of the strings in the value.
zformat -f param format specs ...
zformat -a array sep specs ...
This builtin provides two different forms of formatting. The
first form is selected with the -f option. In this case the
format string will be modified by replacing sequences starting
with a percent sign in it with strings from the specs. Each
spec should be of the form ‘char:string’ which will cause every
appearance of the sequence ‘%char’ in format to be replaced by
the string. The ‘%’ sequence may also contain optional minimum
and maximum field width specifications between the ‘%’ and the
‘char’ in the form ‘%min.maxc’, i.e. the minimum field width is
given first and if the maximum field width is used, it has to
be preceded by a dot. Specifying a minimum field width makes
the result be padded with spaces to the right if the string is
shorter than the requested width. Padding to the left can be
achieved by giving a negative minimum field width. If a maxi-
mum field width is specified, the string will be truncated
after that many characters. After all ‘%’ sequences for the
given specs have been processed, the resulting string is stored
in the parameter param.
The %-escapes also understand ternary expressions in the form
used by prompts. The % is followed by a ‘(’ and then an ordi-
nary format specifier character as described above. There may
be a set of digits either before or after the ‘(’; these spec-
ify a test number, which defaults to zero. Negative numbers
are also allowed. An arbitrary delimiter character follows the
format specifier, which is followed by a piece of ‘true’ text,
the delimiter character again, a piece of ‘false’ text, and a
closing parenthesis. The complete expression (without the dig-
its) thus looks like ‘%(X.text1.text2)’, except that the ‘.’
character is arbitrary. The value given for the format speci-
fier in the char:string expressions is evaluated as a mathemat-
ical expression, and compared with the test number. If they
are the same, text1 is output, else text2 is output. A paren-
thesis may be escaped in text2 as %). Either of text1 or text2
may contain nested %-escapes.
For example:
zformat -f REPLY "The answer is ’%3(c.yes.no)’." c:3
outputs "The answer is ’yes’." to REPLY since the value for the
format specifier c is 3, agreeing with the digit argument to
the ternary expression.
The second form, using the -a option, can be used for aligning
strings. Here, the specs are of the form ‘left:right’ where
‘left’ and ‘right’ are arbitrary strings. These strings are
modified by replacing the colons by the sep string and padding
the left strings with spaces to the right so that the sep
strings in the result (and hence the right strings after them)
are all aligned if the strings are printed below each other.
All strings without a colon are left unchanged and all strings
with an empty right string have the trailing colon removed. In
both cases the lengths of the strings are not used to determine
how the other strings are to be aligned. The resulting strings
are stored in the array.
zregexparse
This implements some internals of the _regex_arguments func-
tion.
zparseopts [ -D ] [ -K ] [ -E ] [ -a array ] [ -A assoc ] specs
This builtin simplifies the parsing of options in positional
parameters, i.e. the set of arguments given by $*. Each spec
describes one option and must be of the form ‘opt[=array]’. If
an option described by opt is found in the positional parame-
ters it is copied into the array specified with the -a option;
if the optional ‘=array’ is given, it is instead copied into
that array.
Note that it is an error to give any spec without an ‘=array’
unless one of the -a or -A options is used.
Unless the -E option is given, parsing stops at the first
string that isn’t described by one of the specs. Even with -E,
parsing always stops at a positional parameter equal to ‘-’ or
‘--’.
The opt description must be one of the following. Any of the
special characters can appear in the option name provided it is
preceded by a backslash.
name
name+ The name is the name of the option without the leading
‘-’. To specify a GNU-style long option, one of the
usual two leading ‘-’ must be included in name; for
example, a ‘--file’ option is represented by a name of
‘-file’.
If a ‘+’ appears after name, the option is appended to
array each time it is found in the positional parame-
ters; without the ‘+’ only the last occurrence of the
option is preserved.
If one of these forms is used, the option takes no argu-
ment, so parsing stops if the next positional parameter
does not also begin with ‘-’ (unless the -E option is
used).
name:
name:-
name:: If one or two colons are given, the option takes an
argument; with one colon, the argument is mandatory and
with two colons it is optional. The argument is
appended to the array after the option itself.
An optional argument is put into the same array element
as the option name (note that this makes empty strings
as arguments indistinguishable). A mandatory argument
is added as a separate element unless the ‘:-’ form is
used, in which case the argument is put into the same
element.
A ‘+’ as described above may appear between the name and
the first colon.
The options of zparseopts itself are:
-a array
As described above, this names the default array in which to
store the recognised options.
-A assoc
If this is given, the options and their values are also put
into an associative array with the option names as keys and the
arguments (if any) as the values.
-D If this option is given, all options found are removed from the
positional parameters of the calling shell or shell function,
up to but not including any not described by the specs. This
is similar to using the shift builtin.
-K With this option, the arrays specified with the -a and -A
options and with the ‘=array’ forms are kept unchanged when
none of the specs for them is used. This allows assignment of
default values to them before calling zparseopts.
-E This changes the parsing rules to not stop at the first string
that isn’t described by one of the specs. It can be used to
test for or (if used together with -D) extract options and
their arguments, ignoring all other options and arguments that
may be in the positional parameters.
For example,
set -- -a -bx -c y -cz baz -cend
zparseopts a=foo b:=bar c+:=bar
will have the effect of
foo=(-a)
bar=(-b x -c y -c z)
The arguments from ‘baz’ on will not be used.
As an example for the -E option, consider:
set -- -a x -b y -c z arg1 arg2
zparseopts -E -D b:=bar
will have the effect of
bar=(-b y)
set -- -a x -c z arg1 arg2
I.e., the option -b and its arguments are taken from the positional
parameters and put into the array bar.
ZSHTCPSYS(1) ZSHTCPSYS(1)
NAME
zshtcpsys - zsh tcp system
DESCRIPTION
A module zsh/net/tcp is provided to provide network I/O over TCP/IP
from within the shell; see its description in zshmodules(1) . This
manual page describes a function suite based on the module. If the
module is installed, the functions are usually installed at the same
time, in which case they will be available for autoloading in the
default function search path. In addition to the zsh/net/tcp module,
the zsh/zselect module is used to implement timeouts on read opera-
tions. For troubleshooting tips, consult the corresponding advice for
the zftp functions described in zshftpsys(1) .
There are functions corresponding to the basic I/O operations open,
close, read and send, named tcp_open etc., as well as a function
tcp_expect for pattern match analysis of data read as input. The sys-
tem makes it easy to receive data from and send data to multiple named
sessions at once. In addition, it can be linked with the shell’s line
editor in such a way that input data is automatically shown at the
terminal. Other facilities available including logging, filtering and
configurable output prompts.
To use the system where it is available, it should be enough to
‘autoload -U tcp_open’ and run tcp_open as documented below to start a
session. The tcp_open function will autoload the remaining functions.
TCP USER FUNCTIONS
Basic I/O
tcp_open [-qz] host port [ sess ]
tcp_open [-qz] [ -s sess | -l sess,... ] ...
tcp_open [-qz] [-a fd | -f fd ] [ sess ]
Open a new session. In the first and simplest form, open a TCP
connection to host host at port port; numeric and symbolic
forms are understood for both.
If sess is given, this becomes the name of the session which
can be used to refer to multiple different TCP connections. If
sess is not given, the function will invent a numeric name
value (note this is not the same as the file descriptor to
which the session is attached). It is recommended that session
names not include ‘funny’ characters, where funny characters
are not well-defined but certainly do not include alphanumerics
or underscores, and certainly do include whitespace.
In the second case, one or more sessions to be opened are given
by name. A single session name is given after -s and a
comma-separated list after -l; both options may be repeated as
many times as necessary. The host and port are read from the
file .ztcp_sessions in the same directory as the user’s zsh
initialisation files, i.e. usually the home directory, but
$ZDOTDIR if that is set. The file consists of lines each giv-
ing a session name and the corresponding host and port, in that
order (note the session name comes first, not last), separated
by whitespace.
The third form allows passive and fake TCP connections. If the
option -a is used, its argument is a file descriptor open for
listening for connections. No function front-end is provided
to open such a file descriptor, but a call to ‘ztcp -l port’
will create one with the file descriptor stored in the parame-
ter $REPLY. The listening port can be closed with ‘ztcp -c
fd’. A call to ‘tcp_open -a fd’ will block until a remote TCP
connection is made to port on the local machine. At this
point, a session is created in the usual way and is largely
indistinguishable from an active connection created with one of
the first two forms.
If the option -f is used, its argument is a file descriptor
which is used directly as if it were a TCP session. How well
the remainder of the TCP function system copes with this
depends on what actually underlies this file descriptor. A
regular file is likely to be unusable; a FIFO (pipe) of some
sort will work better, but note that it is not a good idea for
two different sessions to attempt to read from the same FIFO at
once.
If the option -q is given with any of the three forms, tcp_open
will not print informational messages, although it will in any
case exit with an appropriate status.
If the line editor (zle) is in use, which is typically the case
if the shell is interactive, tcp_open installs a handler inside
zle which will check for new data at the same time as it checks
for keyboard input. This is convenient as the shell consumes
no CPU time while waiting; the test is performed by the operat-
ing system. Giving the option -z to any of the forms of
tcp_open prevents the handler from being installed, so data
must be read explicitly. Note, however, this is not necessary
for executing complete sets of send and read commands from a
function, as zle is not active at this point. Generally speak-
ing, the handler is only active when the shell is waiting for
input at a command prompt or in the vared builtin. The option
has no effect if zle is not active; ‘[[ -o zle]]’ will test for
this.
The first session to be opened becomes the current session and
subsequent calls to tcp_open do not change it. The current
session is stored in the parameter $TCP_SESS; see below for
more detail about the parameters used by the system.
tcp_close [-qn] [ -a | -l sess,... | sess ... ]
Close the named sessions, or the current session if none is
given, or all open sessions if -a is given. The options -l and
-s are both handled for consistency with tcp_open, although the
latter is redundant.
If the session being closed is the current one, $TCP_SESS is
unset, leaving no current session, even if there are other ses-
sions still open.
If the session was opened with tcp_open -f, the file descriptor
is closed so long as it is in the range 0 to 9 accessible
directly from the command line. If the option -n is given, no
attempt will be made to close file descriptors in this case.
The -n option is not used for genuine ztcp session; the file
descriptors are always closed with the session.
If the option -q is given, no informational messages will be
printed.
tcp_read [-bdq] [ -t TO ] [ -T TO ]
[ -a | -u fd ... | -l sess,... | -s sess ...]
Perform a read operation on the current session, or on a list
of sessions if any are given with -u, -l or -s, or all open
sessions if the option -a is given. Any of the -u, -l or -s
options may be repeated or mixed together. The -u option spec-
ifies a file descriptor directly (only those managed by this
system are useful), the other two specify sessions as described
for tcp_open above.
The function checks for new data available on all the sessions
listed. Unless the -b option is given, it will not block wait-
ing for new data. Any one line of data from any of the avail-
able sessions will be read, stored in the parameter $TCP_LINE,
and displayed to standard output unless $TCP_SILENT contains a
non-empty string. When printed to standard output the string
$TCP_PROMPT will be shown at the start of the line; the default
form for this includes the name of the session being read. See
below for more information on these parameters. In this mode,
tcp_read can be called repeatedly until it returns status 2
which indicates all pending input from all specified sessions
has been handled.
With the option -b, equivalent to an infinite timeout, the
function will block until a line is available to read from one
of the specified sessions. However, only a single line is
returned.
The option -d indicates that all pending input should be
drained. In this case tcp_read may process multiple lines in
the manner given above; only the last is stored in $TCP_LINE,
but the complete set is stored in the array $tcp_lines. This
is cleared at the start of each call to tcp_read.
The options -t and -T specify a timeout in seconds, which may
be a floating point number for increased accuracy. With -t the
timeout is applied before each line read. With -T, the timeout
applies to the overall operation, possibly including multiple
read operations if the option -d is present; without this
option, there is no distinction between -t and -T.
The function does not print informational messages, but if the
option -q is given, no error message is printed for a non-exis-
tent session.
A return value of 2 indicates a timeout or no data to read.
Any other non-zero return value indicates some error condition.
See tcp_log for how to control where data is sent by tcp_read.
tcp_send [-nq] [ -s sess | -l sess,... ] data ...
tcp_send [-nq] -a data ...
Send the supplied data strings to all the specified sessions in
turn. The underlying operation differs little from a ‘print
-r’ to the session’s file descriptor, although it attempts to
prevent the shell from dying owing to a SIGPIPE caused by an
attempt to write to a defunct session.
The option -n prevents tcp_send from putting a newline at the
end of the data strings.
The remaining options all behave as for tcp_read.
The data arguments are not further processed once they have
been passed to tcp_send; they are simply passed down to print
-r.
If the parameter $TCP_OUTPUT is a non-empty string and logging
is enabled then the data sent to each session will be echoed to
the log file(s) with $TCP_OUTPUT in front where appropriate,
much in the manner of $TCP_PROMPT.
Session Management
tcp_alias [-q] alias=sess ...
tcp_alias [-q] [ alias ] ...
tcp_alias -d [-q] alias ...
This function is not particularly well tested.
The first form creates an alias for a session name; alias can
then be used to refer to the existing session sess. As many
aliases may be listed as required.
The second form lists any aliases specified, or all aliases if
none.
The third form deletes all the aliases listed. The underlying
sessions are not affected.
The option -q suppresses an inconsistently chosen subset of
error messages.
tcp_log [-asc] [ -n | -N ] [ logfile ]
With an argument logfile, all future input from tcp_read will
be logged to the named file. Unless -a (append) is given, this
file will first be truncated or created empty. With no argu-
ments, show the current status of logging.
With the option -s, per-session logging is enabled. Input from
tcp_read is output to the file logfile.sess. As the session is
automatically discriminated by the filename, the contents are
raw (no $TCP_PROMPT). The option -a applies as above.
Per-session logging and logging of all data in one file are not
mutually exclusive.
The option -c closes all logging, both complete and per-session
logs.
The options -n and -N respectively turn off or restore output
of data read by tcp_read to standard output; hence ‘tcp_log
-cn’ turns off all output by tcp_read.
The function is purely a convenient front end to setting the
parameters $TCP_LOG, $TCP_LOG_SESS, $TCP_SILENT, which are
described below.
tcp_rename old new
Rename session old to session new. The old name becomes
invalid.
tcp_sess [ sess [ command ... ] ]
With no arguments, list all the open sessions and associated
file descriptors. The current session is marked with a star.
For use in functions, direct access to the parameters
$tcp_by_name, $tcp_by_fd and $TCP_SESS is probably more conve-
nient; see below.
With a sess argument, set the current session to sess. This is
equivalent to changing $TCP_SESS directly.
With additional arguments, temporarily set the current session
while executing the string command .... The first argument is
re-evaluated so as to expand aliases etc., but the remaining
arguments are passed through as the appear to tcp_sess. The
original session is restored when tcp_sess exits.
Advanced I/O
tcp_command send-options ... send-arguments ...
This is a convenient front-end to tcp_send. All arguments are
passed to tcp_send, then the function pauses waiting for data.
While data is arriving at least every $TCP_TIMEOUT (default
0.3) seconds, data is handled and printed out according to the
current settings. Status 0 is always returned.
This is generally only useful for interactive use, to prevent
the display becoming fragmented by output returned from the
connection. Within a programme or function it is generally
better to handle reading data by a more explicit method.
tcp_expect [ -q ] [ -p var ] [ -t to | -T TO]
[ -a | -s sess ... | -l sess,... ] pattern ...
Wait for input matching any of the given patterns from any of
the specified sessions. Input is ignored until an input line
matches one of the given patterns; at this point status zero is
returned, the matching line is stored in $TCP_LINE, and the
full set of lines read during the call to tcp_expect is stored
in the array $tcp_expect_lines.
Sessions are specified in the same way as tcp_read: the default
is to use the current session, otherwise the sessions specified
by -a, -s, or -l are used.
Each pattern is a standard zsh extended-globbing pattern; note
that it needs to be quoted to avoid it being expanded immedi-
ately by filename generation. It must match the full line, so
to match a substring there must be a ‘*’ at the start and end.
The line matched against includes the $TCP_PROMPT added by
tcp_read. It is possible to include the globbing flags ‘#b’ or
‘#m’ in the patterns to make backreferences available in the
parameters $MATCH, $match, etc., as described in the base zsh
documentation on pattern matching.
Unlike tcp_read, the default behaviour of tcp_expect is to
block indefinitely until the required input is found. This can
be modified by specifying a timeout with -t or -T; these func-
tion as in tcp_read, specifying a per-read or overall timeout,
respectively, in seconds, as an integer or floating-point num-
ber. As tcp_read, the function returns status 2 if a timeout
occurs.
The function returns as soon as any one of the patterns given
match. If the caller needs to know which of the patterns
matched, the option -p var can be used; on return, $var is set
to the number of the pattern using ordinary zsh indexing, i.e.
the first is 1, and so on. Note the absence of a ‘$’ in front
of var. To avoid clashes, the parameter cannot begin with
‘_expect’.
The option -q is passed directly down to tcp_read.
As all input is done via tcp_read, all the usual rules about
output of lines read apply. One exception is that the parame-
ter $tcp_lines will only reflect the line actually matched by
tcp_expect; use $tcp_expect_lines for the full set of lines
read during the function call.
tcp_proxy
This is a simple-minded function to accept a TCP connection and
execute a command with I/O redirected to the connection.
Extreme caution should be taken as there is no security whatso-
ever and this can leave your computer open to the world. Ide-
ally, it should only be used behind a firewall.
The first argument is a TCP port on which the function will
listen.
The remaining arguments give a command and its arguments to
execute with standard input, standard output and standard error
redirected to the file descriptor on which the TCP session has
been accepted. If no command is given, a new zsh is started.
This gives everyone on your network direct access to your
account, which in many cases will be a bad thing.
The command is run in the background, so tcp_proxy can then
accept new connections. It continues to accept new connections
until interrupted.
tcp_spam [-ertv] [ -a | -s sess | -l sess,... ] cmd ...
Execute ‘cmd ...’ for each session in turn. Note this executes
the command and arguments; it does not send the command line as
data unless the -t (transmit) option is given.
The sessions may be selected explicitly with the standard -a,
-s or -l options, or may be chosen implicitly. If none of the
three options is given the rules are: first, if the array
$tcp_spam_list is set, this is taken as the list of sessions,
otherwise all sessions are taken. Second, any sessions given
in the array $tcp_no_spam_list are removed from the list of
sessions.
Normally, any sessions added by the ‘-a’ flag or when all ses-
sions are chosen implicitly are spammed in alphabetic order;
sessions given by the $tcp_spam_list array or on the command
line are spammed in the order given. The -r flag reverses the
order however it was arrived it.
The -v flag specifies that a $TCP_PROMPT will be output before
each session. This is output after any modification to
TCP_SESS by the user-defined tcp_on_spam function described
below. (Obviously that function is able to generate its own
output.)
If the option -e is present, the line given as cmd ... is exe-
cuted using eval, otherwise it is executed without any further
processing.
tcp_talk
This is a fairly simple-minded attempt to force input to the
line editor to go straight to the default TCP_SESSION.
An escape string, $TCP_TALK_ESCAPE, default ‘:’, is used to
allow access to normal shell operation. If it is on its own at
the start of the line, or followed only by whitespace, the line
editor returns to normal operation. Otherwise, the string and
any following whitespace are skipped and the remainder of the
line executed as shell input without any change of the line
editor’s operating mode.
The current implementation is somewhat deficient in terms of
use of the command history. For this reason, many users will
prefer to use some form of alternative approach for sending
data easily to the current session. One simple approach is to
alias some special character (such as ‘%’) to ‘tcp_command --’.
tcp_wait
The sole argument is an integer or floating point number which
gives the seconds to delay. The shell will do nothing for that
period except wait for input on all TCP sessions by calling
tcp_read -a. This is similar to the interactive behaviour at
the command prompt when zle handlers are installed.
‘One-shot’ file transfer
tcp_point port
tcp_shoot host port
This pair of functions provide a simple way to transfer a file
between two hosts within the shell. Note, however, that bulk
data transfer is currently done using cat. tcp_point reads any
data arriving at port and sends it to standard output;
tcp_shoot connects to port on host and sends its standard
input. Any unused port may be used; the standard mechanism for
picking a port is to think of a random four-digit number above
1024 until one works.
To transfer a file from host woodcock to host springes, on
springes:
tcp_point 8091 >output_file
and on woodcock:
tcp_shoot springes 8091 <input_file
As these two functions do not require tcp_open to set up a TCP
connection first, they may need to be autoloaded separately.
TCP USER-DEFINED FUNCTIONS
Certain functions, if defined by the user, will be called by the func-
tion system in certain contexts. This facility depends on the module
zsh/parameter, which is usually available in interactive shells as the
completion system depends on it. None of the functions need be
defined; they simply provide convenient hooks when necessary.
Typically, these are called after the requested action has been taken,
so that the various parameters will reflect the new state.
tcp_on_alias alias fd
When an alias is defined, this function will be called with two
arguments: the name of the alias, and the file descriptor of
the corresponding session.
tcp_on_close sess fd
This is called with the name of a session being closed and the
file descriptor which corresponded to that session. Both will
be invalid by the time the function is called.
tcp_on_open sess fd
This is called after a new session has been defined with the
session name and file descriptor as arguments.
tcp_on_rename oldsess fd newsess
This is called after a session has been renamed with the three
arguments old session name, file descriptor, new session name.
tcp_on_spam sess command ...
This is called once for each session spammed, just before a
command is executed for a session by tcp_spam. The arguments
are the session name followed by the command list to be exe-
cuted. If tcp_spam was called with the option -t, the first
command will be tcp_send.
This function is called after $TCP_SESS is set to reflect the
session to be spammed, but before any use of it is made. Hence
it is possible to alter the value of $TCP_SESS within this
function. For example, the session arguments to tcp_spam could
include extra information to be stripped off and processed in
tcp_on_spam.
If the function sets the parameter $REPLY to ‘done’, the com-
mand line is not executed; in addition, no prompt is printed
for the -v option to tcp_spam.
tcp_on_unalias alias fd
This is called with the name of an alias and the corresponding
session’s file descriptor after an alias has been deleted.
TCP UTILITY FUNCTIONS
The following functions are used by the TCP function system but will
rarely if ever need to be called directly.
tcp_fd_handler
This is the function installed by tcp_open for handling input
from within the line editor, if that is required. It is in the
format documented for the builtin ‘zle -F’ in zshzle(1) .
While active, the function sets the parameter TCP_HAN-
DLER_ACTIVE to 1. This allows shell code called internally
(for example, by setting tcp_on_read) to tell if is being
called when the shell is otherwise idle at the editor prompt.
tcp_output [ -q ] -P prompt -F fd -S sess
This function is used for both logging and handling output to
standard output, from within tcp_read and (if $TCP_OUTPUT is
set) tcp_send.
The prompt to use is specified by -P; the default is the empty
string. It can contain:
%c Expands to 1 if the session is the current session, oth-
erwise 0. Used with ternary expresions such as
‘%(c.-.+)’ to output ‘+’ for the current session and ‘-’
otherwise.
%f Replaced by the session’s file descriptor.
%s Replaced by the session name.
%% Replaced by a single ‘%’.
The option -q suppresses output to standard output, but not to
any log files which are configured.
The -S and -F options are used to pass in the session name and
file descriptor for possible replacement in the prompt.
TCP USER PARAMETERS
Parameters follow the usual convention that uppercase is used for
scalars and integers, while lowercase is used for normal and associa-
tive array. It is always safe for user code to read these parameters.
Some parameters may also be set; these are noted explicitly. Others
are included in this group as they are set by the function system for
the user’s benefit, i.e. setting them is typically not useful but is
benign.
It is often also useful to make settable parameters local to a func-
tion. For example, ‘local TCP_SILENT=1’ specifies that data read dur-
ing the function call will not be printed to standard output, regard-
less of the setting outside the function. Likewise, ‘local
TCP_SESS=sess’ sets a session for the duration of a function, and
‘local TCP_PROMPT=’ specifies that no prompt is used for input during
the function.
tcp_expect_lines
Array. The set of lines read during the last call to
tcp_expect, including the last ($TCP_LINE).
tcp_filter
Array. May be set directly. A set of extended globbing pat-
terns which, if matched in tcp_output, will cause the line not
to be printed to standard output. The patterns should be
defined as described for the arguments to tcp_expect. Output
of line to log files is not affected.
TCP_HANDLER_ACTIVE
Scalar. Set to 1 within tcp_fd_handler to indicate to func-
tions called recursively that they have been called during an
editor session. Otherwise unset.
TCP_LINE
The last line read by tcp_read, and hence also tcp_expect.
TCP_LINE_FD
The file descriptor from which $TCP_LINE was read.
${tcp_by_fd[$TCP_LINE_FD]} will give the corresponding session
name.
tcp_lines
Array. The set of lines read during the last call to tcp_read,
including the last ($TCP_LINE).
TCP_LOG
May be set directly, although it is also controlled by tcp_log.
The name of a file to which output from all sessions will be
sent. The output is proceeded by the usual $TCP_PROMPT. If it
is not an absolute path name, it will follow the user’s current
directory.
TCP_LOG_SESS
May be set directly, although it is also controlled by tcp_log.
The prefix for a set of files to which output from each session
separately will be sent; the full filename is
${TCP_LOG_SESS}.sess. Output to each file is raw; no prompt is
added. If it is not an absolute path name, it will follow the
user’s current directory.
tcp_no_spam_list
Array. May be set directly. See tcp_spam for how this is
used.
TCP_OUTPUT
May be set directly. If a non-empty string, any data sent to a
session by tcp_send will be logged. This parameter gives the
prompt to be used in a file specified by $TCP_LOG but not in a
file generated from $TCP_LOG_SESS. The prompt string has the
same format as TCP_PROMPT and the same rules for its use apply.
TCP_PROMPT
May be set directly. Used as the prefix for data read by
tcp_read which is printed to standard output or to the log file
given by $TCP_LOG, if any. Any ‘%s’, ‘%f’ or ‘%%’ occurring in
the string will be replaced by the name of the session, the
session’s underlying file descriptor, or a single ‘%’, respec-
tively. The expression ‘%c’ expands to 1 if the session being
read is the current session, else 0; this is most useful in
ternary expressions such as ‘%(c.-.+)’ which outputs ‘+’ if the
session is the current one, else ‘-’.
TCP_READ_DEBUG
May be set directly. If this has non-zero length, tcp_read
will give some limited diagnostics about data being read.
TCP_SECONDS_START
This value is created and initialised to zero by tcp_open.
The functions tcp_read and tcp_expect use the shell’s SECONDS
parameter for their own timing purposes. If that parameter is
not of floating point type on entry to one of the functions, it
will create a local parameter SECONDS which is floating point
and set the parameter TCP_SECONDS_START to the previous value
of $SECONDS. If the parameter is already floating point, it is
used without a local copy being created and TCP_SECONDS_START
is not set. As the global value is zero, the shell elapsed
time is guaranteed to be the sum of $SECONDS and $TCP_SEC-
ONDS_START.
This can be avoided by setting SECONDS globally to a floating
point value using ‘typeset -F SECONDS’; then the TCP functions
will never make a local copy and never set TCP_SECONDS_START to
a non-zero value.
TCP_SESS
May be set directly. The current session; must refer to one of
the sessions established by tcp_open.
TCP_SILENT
May be set directly, although it is also controlled by tcp_log.
If of non-zero length, data read by tcp_read will not be writ-
ten to standard output, though may still be written to a log
file.
tcp_spam_list
Array. May be set directly. See the description of the func-
tion tcp_spam for how this is used.
TCP_TALK_ESCAPE
May be set directly. See the description of the function
tcp_talk for how this is used.
TCP_TIMEOUT
May be set directly. Currently this is only used by the func-
tion tcp_command, see above.
TCP USER-DEFINED PARAMETERS
The following parameters are not set by the function system, but have
a special effect if set by the user.
tcp_on_read
This should be an associative array; if it is not, the
behaviour is undefined. Each key is the name of a shell func-
tion or other command, and the corresponding value is a shell
pattern (using EXTENDED_GLOB). Every line read from a TCP ses-
sion directly or indirectly using tcp_read (which includes
lines read by tcp_expect) is compared against the pattern. If
the line matches, the command given in the key is called with
two arguments: the name of the session from which the line was
read, and the line itself.
If any function called to handle a line returns a non-zero sta-
tus, the line is not output. Thus a tcp_on_read handler con-
taining only the instruction ‘return 1’ can be used to suppress
output of particular lines (see, however, tcp_filter above).
However, the line is still stored in TCP_LINE and tcp_lines;
this occurs after all tcp_on_read processing.
TCP UTILITY PARAMETERS
These parameters are controlled by the function system; they may be
read directly, but should not usually be set by user code.
tcp_aliases
Associative array. The keys are the names of sessions estab-
lished with tcp_open; each value is a space-separated list of
aliases which refer to that session.
tcp_by_fd
Associative array. The keys are session file descriptors; each
value is the name of that session.
tcp_by_name
Associative array. The keys are the names of sessions; each
value is the file descriptor associated with that session.
TCP EXAMPLES
Here is a trivial example using a remote calculator.
TO create a calculator server on port 7337 (see the dc manual page for
quite how infuriating the underlying command is):
tcp_proxy 7337 dc
To connect to this from the same host with a session also named ‘dc’:
tcp_open localhost 7337 dc
To send a command to the remote session and wait a short while for
output (assuming dc is the current session):
tcp_command 2 4 + p
To close the session:
tcp_close
The tcp_proxy needs to be killed to be stopped. Note this will not
usually kill any connections which have already been accepted, and
also that the port is not immediately available for reuse.
The following chunk of code puts a list of sessions into an xterm
header, with the current session followed by a star.
print -n "\033]2;TCP:" ${(k)tcp_by_name:/$TCP_SESS/$TCP_SESS\*} "\a"
TCP BUGS
The function tcp_read uses the shell’s normal read builtin. As this
reads a complete line at once, data arriving without a terminating
newline can cause the function to block indefinitely.
Though the function suite works well for interactive use and for data
arriving in small amounts, the performance when large amounts of data
ZSHZFTPSYS(1) ZSHZFTPSYS(1)
are being exchanged is likely to be extremely poor.
NAME
zshzftpsys - zftp function front-end
DESCRIPTION
This describes the set of shell functions supplied with the source
distribution as an interface to the zftp builtin command, allowing you
to perform FTP operations from the shell command line or within func-
tions or scripts. The interface is similar to a traditional FTP
client (e.g. the ftp command itself, see ftp(1)), but as it is
entirely done within the shell all the familiar completion, editing
and globbing features, and so on, are present, and macros are particu-
larly simple to write as they are just ordinary shell functions.
The prerequisite is that the zftp command, as described in zshmod-
ules(1) , must be available in the version of zsh installed at your
site. If the shell is configured to load new commands at run time, it
probably is: typing ‘zmodload zsh/zftp’ will make sure (if that runs
silently, it has worked). If this is not the case, it is possible
zftp was linked into the shell anyway: to test this, type ‘which zftp’
and if zftp is available you will get the message ‘zftp: shell
built-in command’.
Commands given directly with zftp builtin may be interspersed between
the functions in this suite; in a few cases, using zftp directly may
cause some of the status information stored in shell parameters to
become invalid. Note in particular the description of the variables
$ZFTP_TMOUT, $ZFTP_PREFS and $ZFTP_VERBOSE for zftp.
INSTALLATION
You should make sure all the functions from the Functions/Zftp direc-
tory of the source distribution are available; they all begin with the
two letters ‘zf’. They may already have been installed on your sys-
tem; otherwise, you will need to find them and copy them. The direc-
tory should appear as one of the elements of the $fpath array (this
should already be the case if they were installed), and at least the
function zfinit should be autoloaded; it will autoload the rest.
Finally, to initialize the use of the system you need to call the
zfinit function. The following code in your .zshrc will arrange for
this; assume the functions are stored in the directory ~/myfns:
fpath=(~/myfns $fpath)
autoload -U zfinit
zfinit
Note that zfinit assumes you are using the zmodload method to load the
zftp command. If it is already built into the shell, change zfinit to
zfinit -n. It is helpful (though not essential) if the call to zfinit
appears after any code to initialize the new completion system, else
unnecessary compctl commands will be given.
FUNCTIONS
The sequence of operations in performing a file transfer is essen-
tially the same as that in a standard FTP client. Note that, due to a
quirk of the shell’s getopts builtin, for those functions that handle
options you must use ‘--’ rather than ‘-’ to ensure the remaining
arguments are treated literally (a single ‘-’ is treated as an argu-
ment).
Opening a connection
zfparams [ host [ user [ password ... ] ] ]
Set or show the parameters for a future zfopen with no argu-
ments. If no arguments are given, the current parameters are
displayed (the password will be shown as a line of asterisks).
If a host is given, and either the user or password is not,
they will be prompted for; also, any parameter given as ‘?’
will be prompted for, and if the ‘?’ is followed by a string,
that will be used as the prompt. As zfopen calls zfparams to
store the parameters, this usually need not be called directly.
A single argument ‘-’ will delete the stored parameters. This
will also cause the memory of the last directory (and so on) on
the other host to be deleted.
zfopen [ -1 ] [ host [ user [ password [ account ] ] ] ]
If host is present, open a connection to that host under user-
name user with password password (and, on the rare occasions
when it is necessary, account account). If a necessary parame-
ter is missing or given as ‘?’ it will be prompted for. If
host is not present, use a previously stored set of parameters.
If the command was successful, and the terminal is compatible
with xterm or is sun-cmd, a summary will appear in the title
bar, giving the local host:directory and the remote host:direc-
tory; this is handled by the function zftp_chpwd, described
below.
Normally, the host, user and password are internally recorded
for later re-opening, either by a zfopen with no arguments, or
automatically (see below). With the option ‘-1’, no informa-
tion is stored. Also, if an open command with arguments
failed, the parameters will not be retained (and any previous
parameters will also be deleted). A zfopen on its own, or a
zfopen -1, never alters the stored parameters.
Both zfopen and zfanon (but not zfparams) understand URLs of
the form ftp://host/path... as meaning to connect to the host,
then change directory to path (which must be a directory, not a
file). The ‘ftp://’ can be omitted; the trailing ‘/’ is enough
to trigger recognition of the path. Note prefixes other than
‘ftp:’ are not recognized, and that all characters after the
first slash beyond host are significant in path.
zfanon [ -1 ] host
Open a connection host for anonymous FTP. The username used is
‘anonymous’. The password (which will be reported the first
time) is generated as user@host; this is then stored in the
shell parameter $EMAIL_ADDR which can alternatively be set man-
ually to a suitable string.
Directory management
zfcd [ dir ]
zfcd -
zfcd old new
Change the current directory on the remote server: this is
implemented to have many of the features of the shell builtin
cd.
In the first form with dir present, change to the directory
dir. The command ‘zfcd ..’ is treated specially, so is guaran-
teed to work on non-UNIX servers (note this is handled inter-
nally by zftp). If dir is omitted, has the effect of ‘zfcd ~’.
The second form changes to the directory previously current.
The third form attempts to change the current directory by
replacing the first occurrence of the string old with the
string new in the current directory.
Note that in this command, and indeed anywhere a remote file-
name is expected, the string which on the local host corre-
sponds to ‘~’ is converted back to a ‘~’ before being passed to
the remote machine. This is convenient because of the way
expansion is performed on the command line before zfcd receives
a string. For example, suppose the command is ‘zfcd ~/foo’.
The shell will expand this to a full path such as ‘zfcd
/home/user2/pws/foo’. At this stage, zfcd recognises the ini-
tial path as corresponding to ‘~’ and will send the directory
to the remote host as ~/foo, so that the ‘~’ will be expanded
by the server to the correct remote host directory. Other
named directories of the form ‘~name’ are not treated in this
fashion.
zfhere Change directory on the remote server to the one corresponding
to the current local directory, with special handling of ‘~’ as
in zfcd. For example, if the current local directory is
~/foo/bar, then zfhere performs the effect of ‘zfcd ~/foo/bar’.
zfdir [ -rfd ] [ - ] [ dir-options ] [ dir ]
Produce a long directory listing. The arguments dir-options
and dir are passed directly to the server and their effect is
implementation dependent, but specifying a particular remote
directory dir is usually possible. The output is passed
through a pager given by the environment variable $PAGER, or
‘more’ if that is not set.
The directory is usually cached for re-use. In fact, two
caches are maintained. One is for use when there is no
dir-options or dir, i.e. a full listing of the current remote
directory; it is flushed when the current remote directory
changes. The other is kept for repeated use of zfdir with the
same arguments; for example, repeated use of ‘zfdir /pub/gnu’
will only require the directory to be retrieved on the first
call. Alternatively, this cache can be re-viewed with the -r
option. As relative directories will confuse zfdir, the -f
option can be used to force the cache to be flushed before the
directory is listed. The option -d will delete both caches
without showing a directory listing; it will also delete the
cache of file names in the current remote directory, if any.
zfls [ ls-options ] [ dir ]
List files on the remote server. With no arguments, this will
produce a simple list of file names for the current remote
directory. Any arguments are passed directly to the server.
No pager and no caching is used.
Status commands
zftype [ type ]
With no arguments, show the type of data to be transferred,
usually ASCII or binary. With an argument, change the type:
the types ‘A’ or ‘ASCII’ for ASCII data and ‘B’ or ‘BINARY’,
‘I’ or ‘IMAGE’ for binary data are understood case-insensi-
tively.
zfstat [ -v ]
Show the status of the current or last connection, as well as
the status of some of zftp’s status variables. With the -v
option, a more verbose listing is produced by querying the
server for its version of events, too.
Retrieving files
The commands for retrieving files all take at least two options. -G
suppresses remote filename expansion which would otherwise be per-
formed (see below for a more detailed description of that). -t
attempts to set the modification time of the local file to that of the
remote file: this requires version 5 of perl, see the description of
the function zfrtime below for more information.
zfget [ -Gtc ] file1 ...
Retrieve all the listed files file1 ... one at a time from the
remote server. If a file contains a ‘/’, the full name is
passed to the remote server, but the file is stored locally
under the name given by the part after the final ‘/’. The
option -c (cat) forces all files to be sent as a single stream
to standard output; in this case the -t option has no effect.
zfuget [ -Gvst ] file1 ...
As zfget, but only retrieve files where the version on the
remote server is newer (has a later modification time), or
where the local file does not exist. If the remote file is
older but the files have different sizes, or if the sizes are
the same but the remote file is newer, the user will usually be
queried. With the option -s, the command runs silently and
will always retrieve the file in either of those two cases.
With the option -v, the command prints more information about
the files while it is working out whether or not to transfer
them.
zfcget [ -Gt ] file1 ...
As zfget, but if any of the local files exists, and is shorter
than the corresponding remote file, the command assumes that it
is the result of a partially completed transfer and attempts to
transfer the rest of the file. This is useful on a poor con-
nection which keeps failing.
Note that this requires a commonly implemented, but non-stan-
dard, version of the FTP protocol, so is not guaranteed to work
on all servers.
zfgcp [ -Gt ] remote-file local-file
zfgcp [ -Gt ] rfile1 ... ldir
This retrieves files from the remote server with arguments
behaving similarly to the cp command.
In the first form, copy remote-file from the server to the
local file local-file.
In the second form, copy all the remote files rfile1 ... into
the local directory ldir retaining the same basenames. This
assumes UNIX directory semantics.
Sending files
zfput [ -r ] file1 ...
Send all the file1 ... given separately to the remote server.
If a filename contains a ‘/’, the full filename is used locally
to find the file, but only the basename is used for the remote
file name.
With the option -r, if any of the files are directories they
are sent recursively with all their subdirectories, including
files beginning with ‘.’. This requires that the remote
machine understand UNIX file semantics, since ‘/’ is used as a
directory separator.
zfuput [ -vs ] file1 ...
As zfput, but only send files which are newer than their local
equivalents, or if the remote file does not exist. The logic
is the same as for zfuget, but reversed between local and
remote files.
zfcput file1 ...
As zfput, but if any remote file already exists and is shorter
than the local equivalent, assume it is the result of an incom-
plete transfer and send the rest of the file to append to the
existing part. As the FTP append command is part of the stan-
dard set, this is in principle more likely to work than zfcget.
zfpcp local-file remote-file
zfpcp lfile1 ... rdir
This sends files to the remote server with arguments behaving
similarly to the cp command.
With two arguments, copy local-file to the server as
remote-file.
With more than two arguments, copy all the local files lfile1
... into the existing remote directory rdir retaining the same
basenames. This assumes UNIX directory semantics.
A problem arises if you attempt to use zfpcp lfile1 rdir, i.e.
the second form of copying but with two arguments, as the com-
mand has no simple way of knowing if rdir corresponds to a
directory or a filename. It attempts to resolve this in vari-
ous ways. First, if the rdir argument is ‘.’ or ‘..’ or ends
in a slash, it is assumed to be a directory. Secondly, if the
operation of copying to a remote file in the first form failed,
and the remote server sends back the expected failure code 553
and a reply including the string ‘Is a directory’, then zfpcp
will retry using the second form.
Closing the connection
zfclose
Close the connection.
Session management
zfsession [ -lvod ] [ sessname ]
Allows you to manage multiple FTP sessions at once. By
default, connections take place in a session called ‘default’;
by giving the command ‘zfsession sessname’ you can change to a
new or existing session with a name of your choice. The new
session remembers its own connection, as well as associated
shell parameters, and also the host/user parameters set by
zfparams. Hence you can have different sessions set up to con-
nect to different hosts, each remembering the appropriate host,
user and password.
With no arguments, zfsession prints the name of the current
session; with the option -l it lists all sessions which cur-
rently exist, and with the option -v it gives a verbose list
showing the host and directory for each session, where the cur-
rent session is marked with an asterisk. With -o, it will
switch to the most recent previous session.
With -d, the given session (or else the current one) is
removed; everything to do with it is completely forgotten. If
it was the only session, a new session called ‘default’ is cre-
ated and made current. It is safest not to delete sessions
while background commands using zftp are active.
zftransfer sess1:file1 sess2:file2
Transfer files between two sessions; no local copy is made.
The file is read from the session sess1 as file1 and written to
session sess2 as file file2; file1 and file2 may be relative to
the current directories of the session. Either sess1 or sess2
may be omitted (though the colon should be retained if there is
a possibility of a colon appearing in the file name) and
defaults to the current session; file2 may be omitted or may
end with a slash, in which case the basename of file1 will be
added. The sessions sess1 and sess2 must be distinct.
The operation is performed using pipes, so it is required that
the connections still be valid in a subshell, which is not the
case under versions of some operating systems, presumably due
to a system bug.
Bookmarks
The two functions zfmark and zfgoto allow you to ‘bookmark’ the
present location (host, user and directory) of the current FTP connec-
tion for later use. The file to be used for storing and retrieving
bookmarks is given by the parameter $ZFTP_BMFILE; if not set when one
of the two functions is called, it will be set to the file .zfbkmarks
in the directory where your zsh startup files live (usually ~).
zfmark [ bookmark ]
If given an argument, mark the current host, user and directory
under the name bookmark for later use by zfgoto. If there is
no connection open, use the values for the last connection
immediately before it was closed; it is an error if there was
none. Any existing bookmark under the same name will be
silently replaced.
If not given an argument, list the existing bookmarks and the
points to which they refer in the form user@host:directory;
this is the format in which they are stored, and the file may
be edited directly.
zfgoto [ -n ] bookmark
Return to the location given by bookmark, as previously set by
zfmark. If the location has user ‘ftp’ or ‘anonymous’, open
the connection with zfanon, so that no password is required.
If the user and host parameters match those stored for the cur-
rent session, if any, those will be used, and again no password
is required. Otherwise a password will be prompted for.
With the option -n, the bookmark is taken to be a nickname
stored by the ncftp program in its bookmark file, which is
assumed to be ~/.ncftp/bookmarks. The function works identi-
cally in other ways. Note that there is no mechanism for
adding or modifying ncftp bookmarks from the zftp functions.
Other functions
Mostly, these functions will not be called directly (apart from
zfinit), but are described here for completeness. You may wish to
alter zftp_chpwd and zftp_progress, in particular.
zfinit [ -n ]
As described above, this is used to initialize the zftp func-
tion system. The -n option should be used if the zftp command
is already built into the shell.
zfautocheck [ -dn ]
This function is called to implement automatic reopening
behaviour, as described in more detail below. The options must
appear in the first argument; -n prevents the command from
changing to the old directory, while -d prevents it from set-
ting the variable do_close, which it otherwise does as a flag
for automatically closing the connection after a transfer. The
host and directory for the last session are stored in the vari-
able $zflastsession, but the internal host/user/password param-
eters must also be correctly set.
zfcd_match prefix suffix
This performs matching for completion of remote directory
names. If the remote server is UNIX, it will attempt to per-
suade the server to list the remote directory with subdirecto-
ries marked, which usually works but is not guaranteed. On
other hosts it simply calls zfget_match and hence completes all
files, not just directories. On some systems, directories may
not even look like filenames.
zfget_match prefix suffix
This performs matching for completion of remote filenames. It
caches files for the current directory (only) in the shell
parameter $zftp_fcache. It is in the form to be called by the
-K option of compctl, but also works when called from a wid-
get-style completion function with prefix and suffix set appro-
priately.
zfrglob varname
Perform remote globbing, as describes in more detail below.
varname is the name of a variable containing the pattern to be
expanded; if there were any matches, the same variable will be
set to the expanded set of filenames on return.
zfrtime lfile rfile [ time ]
Set the local file lfile to have the same modification time as
the remote file rfile, or the explicit time time in FTP format
CCYYMMDDhhmmSS for the GMT timezone.
Currently this requires perl version 5 to perform the conver-
sion from GMT to local time. This is unfortunately difficult
to do using shell code alone.
zftp_chpwd
This function is called every time a connection is opened, or
closed, or the remote directory changes. This version alters
the title bar of an xterm-compatible or sun-cmd terminal emula-
tor to reflect the local and remote hostnames and current
directories. It works best when combined with the function
chpwd. In particular, a function of the form
chpwd() {
if [[ -n $ZFTP_USER ]]; then
zftp_chpwd
else
# usual chpwd e.g put host:directory in title bar
fi
}
fits in well.
zftp_progress
This function shows the status of the transfer. It will not
write anything unless the output is going to a terminal; how-
ever, if you transfer files in the background, you should turn
off progress reports by hand using ‘zstyle ’:zftp:*’ progress
none’. Note also that if you alter it, any output must be to
standard error, as standard output may be a file being
received. The form of the progress meter, or whether it is
used at all, can be configured without altering the function,
as described in the next section.
zffcache
This is used to implement caching of files in the current
directory for each session separately. It is used by
zfget_match and zfrglob.
MISCELLANEOUS FEATURES
Configuration
Various styles are available using the standard shell style mechanism,
described in zshmodules(1). Briefly, the command ‘zstyle ’:zftp:*’
style value ...’. defines the style to have value value; more than
one value may be given, although that is not useful in the cases
described here. These values will then be used throughout the zftp
function system. For more precise control, the first argument, which
gives a context in which the style applies, can be modified to include
a particular function, as for example ‘:zftp:zfget’: the style will
then have the given value only in the zfget function. Values for the
same style in different contexts may be set; the most specific func-
tion will be used, where strings are held to be more specific than
patterns, and longer patterns and shorter patterns. Note that only
the top level function name, as called by the user, is used; calling
of lower level functions is transparent to the user. Hence modifica-
tions to the title bar in zftp_chpwd use the contexts :zftp:zfopen,
:zftp:zfcd, etc., depending where it was called from. The following
styles are understood:
progress
Controls the way that zftp_progress reports on the progress of
a transfer. If empty, unset, or ‘none’, no progress report is
made; if ‘bar’ a growing bar of inverse video is shown; if
‘percent’ (or any other string, though this may change in
future), the percentage of the file transferred is shown. The
bar meter requires that the width of the terminal be available
via the $COLUMNS parameter (normally this is set automati-
cally). If the size of the file being transferred is not
available, bar and percent meters will simply show the number
of bytes transferred so far.
When zfinit is run, if this style is not defined for the con-
text :zftp:*, it will be set to ‘bar’.
update Specifies the minimum time interval between updates of the
progress meter in seconds. No update is made unless new data
has been received, so the actual time interval is limited only
by $ZFTP_TIMEOUT.
As described for progress, zfinit will force this to default to
1.
remote-glob
If set to ‘1’, ‘yes’ or ‘true’, filename generation (globbing)
is performed on the remote machine instead of by zsh itself;
see below.
titlebar
If set to ‘1’, ‘yes’ or ‘true’, zftp_chpwd will put the remote
host and remote directory into the titlebar of terminal emula-
tors such as xterm or sun-cmd that allow this.
As described for progress, zfinit will force this to default to
1.
chpwd If set to ‘1’ ‘yes’ or ‘true’, zftp_chpwd will call the func-
tion chpwd when a connection is closed. This is useful if the
remote host details were put into the terminal title bar by
zftp_chpwd and your usual chpwd also modifies the title bar.
When zfinit is run, it will determine whether chpwd exists and
if so it will set the default value for the style to 1 if none
exists already.
Note that there is also an associative array zfconfig which contains
values used by the function system. This should not be modified or
overwritten.
Remote globbing
The commands for retrieving files usually perform filename generation
(globbing) on their arguments; this can be turned off by passing the
option -G to each of the commands. Normally this operates by retriev-
ing a complete list of files for the directory in question, then
matching these locally against the pattern supplied. This has the
advantage that the full range of zsh patterns (respecting the setting
of the option EXTENDED_GLOB) can be used. However, it means that the
directory part of a filename will not be expanded and must be given
exactly. If the remote server does not support the UNIX directory
semantics, directory handling is problematic and it is recommended
that globbing only be used within the current directory. The list of
files in the current directory, if retrieved, will be cached, so that
subsequent globs in the same directory without an intervening zfcd are
much faster.
If the remote-glob style (see above) is set, globbing is instead per-
formed on the remote host: the server is asked for a list of matching
files. This is highly dependent on how the server is implemented,
though typically UNIX servers will provide support for basic glob pat-
terns. This may in some cases be faster, as it avoids retrieving the
entire list of directory contents.
Automatic and temporary reopening
As described for the zfopen command, a subsequent zfopen with no
parameters will reopen the connection to the last host (this includes
connections made with the zfanon command). Opened in this fashion,
the connection starts in the default remote directory and will remain
open until explicitly closed.
Automatic re-opening is also available. If a connection is not cur-
rently open and a command requiring a connection is given, the last
connection is implicitly reopened. In this case the directory which
was current when the connection was closed again becomes the current
directory (unless, of course, the command given changes it). Auto-
matic reopening will also take place if the connection was close by
the remote server for whatever reason (e.g. a timeout). It is not
available if the -1 option to zfopen or zfanon was used.
Furthermore, if the command issued is a file transfer, the connection
will be closed after the transfer is finished, hence providing a
one-shot mode for transfers. This does not apply to directory chang-
ing or listing commands; for example a zfdir may reopen a connection
but will leave it open. Also, automatic closure will only ever happen
in the same command as automatic opening, i.e a zfdir directly fol-
lowed by a zfget will never close the connection automatically.
Information about the previous connection is given by the zfstat func-
tion. So, for example, if that reports:
Session: default
Not connected.
Last session: ftp.bar.com:/pub/textfiles
then the command zfget file.txt will attempt to reopen a connection to
ftp.bar.com, retrieve the file /pub/textfiles/file.txt, and immedi-
ately close the connection again. On the other hand, zfcd .. will
open the connection in the directory /pub and leave it open.
Note that all the above is local to each session; if you return to a
previous session, the connection for that session is the one which
will be reopened.
Completion
Completion of local and remote files, directories, sessions and book-
marks is supported. The older, compctl-style completion is defined
when zfinit is called; support for the new widget-based completion
system is provided in the function Completion/Zsh/Command/_zftp, which
should be installed with the other functions of the completion system
ZSHCONTRIB(1) ZSHCONTRIB(1)
and hence should automatically be available.
NAME
zshcontrib - user contributions to zsh
DESCRIPTION
The Zsh source distribution includes a number of items contributed by
the user community. These are not inherently a part of the shell, and
some may not be available in every zsh installation. The most signif-
icant of these are documented here. For documentation on other con-
tributed items such as shell functions, look for comments in the func-
tion source files.
UTILITIES
Accessing On-Line Help
The key sequence ESC h is normally bound by ZLE to execute the
run-help widget (see zshzle(1)). This invokes the run-help command
with the command word from the current input line as its argument. By
default, run-help is an alias for the man command, so this often fails
when the command word is a shell builtin or a user-defined function.
By redefining the run-help alias, one can improve the on-line help
provided by the shell.
The helpfiles utility, found in the Util directory of the distribu-
tion, is a Perl program that can be used to process the zsh manual to
produce a separate help file for each shell builtin and for many other
shell features as well. The autoloadable run-help function, found in
Functions/Misc, searches for these helpfiles and performs several
other tests to produce the most complete help possible for the com-
mand.
There may already be a directory of help files on your system; look in
/usr/share/zsh or /usr/local/share/zsh and subdirectories below those,
or ask your system administrator.
To create your own help files with helpfiles, choose or create a
directory where the individual command help files will reside. For
example, you might choose ~/zsh_help. If you unpacked the zsh distri-
bution in your home directory, you would use the commands:
mkdir ~/zsh_help
cd ~/zsh_help
man zshall | colcrt - | \
perl ~/zsh-4.2.0/Util/helpfiles
Next, to use the run-help function, you need to add lines something
like the following to your .zshrc or equivalent startup file:
unalias run-help
autoload run-help
HELPDIR=~/zsh_help
The HELPDIR parameter tells run-help where to look for the help files.
If your system already has a help file directory installed, set
HELPDIR to the path of that directory instead.
Note that in order for ‘autoload run-help’ to work, the run-help file
must be in one of the directories named in your fpath array (see zsh-
param(1)). This should already be the case if you have a standard zsh
installation; if it is not, copy Functions/Misc/run-help to an appro-
priate directory.
Recompiling Functions
If you frequently edit your zsh functions, or periodically update your
zsh installation to track the latest developments, you may find that
function digests compiled with the zcompile builtin are frequently out
of date with respect to the function source files. This is not usu-
ally a problem, because zsh always looks for the newest file when
loading a function, but it may cause slower shell startup and function
loading. Also, if a digest file is explicitly used as an element of
fpath, zsh won’t check whether any of its source files has changed.
The zrecompile autoloadable function, found in Functions/Misc, can be
used to keep function digests up to date.
zrecompile [ -qt ] [ name ... ]
zrecompile [ -qt ] -p args [ -- args ... ]
This tries to find *.zwc files and automatically re-compile
them if at least one of the original files is newer than the
compiled file. This works only if the names stored in the com-
piled files are full paths or are relative to the directory
that contains the .zwc file.
In the first form, each name is the name of a compiled file or
a directory containing *.zwc files that should be checked. If
no arguments are given, the directories and *.zwc files in
fpath are used.
When -t is given, no compilation is performed, but a return
status of zero (true) is set if there are files that need to be
re-compiled and non-zero (false) otherwise. The -q option qui-
ets the chatty output that describes what zrecompile is doing.
Without the -t option, the return status is zero if all files
that needed re-compilation could be compiled and non-zero if
compilation for at least one of the files failed.
If the -p option is given, the args are interpreted as one or
more sets of arguments for zcompile, separated by ‘--’. For
example:
zrecompile -p \
-R ~/.zshrc -- \
-M ~/.zcompdump -- \
~/zsh/comp.zwc ~/zsh/Completion/*/_*
This compiles ~/.zshrc into ~/.zshrc.zwc if that doesn’t exist
or if it is older than ~/.zshrc. The compiled file will be
marked for reading instead of mapping. The same is done for
~/.zcompdump and ~/.zcompdump.zwc, but this compiled file is
marked for mapping. The last line re-creates the file
~/zsh/comp.zwc if any of the files matching the given pattern
is newer than it.
Without the -p option, zrecompile does not create function
digests that do not already exist, nor does it add new func-
tions to the digest.
The following shell loop is an example of a method for creating func-
tion digests for all functions in your fpath, assuming that you have
write permission to the directories:
for ((i=1; i <= $#fpath; ++i)); do
dir=$fpath[i]
zwc=${dir:t}.zwc
if [[ $dir == (.|..) || $dir == (.|..)/* ]]; then
continue
fi
files=($dir/*(N-.))
if [[ -w $dir:h && -n $files ]]; then
files=(${${(M)files%/*/*}#/})
if ( cd $dir:h &&
zrecompile -p -U -z $zwc $files ); then
fpath[i]=$fpath[i].zwc
fi
fi
done
The -U and -z options are appropriate for functions in the default zsh
installation fpath; you may need to use different options for your
personal function directories.
Once the digests have been created and your fpath modified to refer to
them, you can keep them up to date by running zrecompile with no argu-
ments.
Keyboard Definition
The large number of possible combinations of keyboards, workstations,
terminals, emulators, and window systems makes it impossible for zsh
to have built-in key bindings for every situation. The zkbd utility,
found in Functions/Misc, can help you quickly create key bindings for
your configuration.
Run zkbd either as an autoloaded function, or as a shell script:
zsh -f ~/zsh-4.2.0/Functions/Misc/zkbd
When you run zkbd, it first asks you to enter your terminal type; if
the default it offers is correct, just press return. It then asks you
to press a number of different keys to determine characteristics of
your keyboard and terminal; zkbd warns you if it finds anything out of
the ordinary, such as a Delete key that sends neither ^H nor ^?.
The keystrokes read by zkbd are recorded as a definition for an asso-
ciative array named key, written to a file in the subdirectory .zkbd
within either your HOME or ZDOTDIR directory. The name of the file is
composed from the TERM, VENDOR and OSTYPE parameters, joined by
hyphens.
You may read this file into your .zshrc or another startup file with
the "source" or "." commands, then reference the key parameter in
bindkey commands, like this:
source ${ZDOTDIR:-$HOME}/.zkbd/$TERM-$VENDOR-$OSTYPE
[[ -n ${key[Left]} ]] && bindkey "${key[Left]}" backward-char
[[ -n ${key[Right]} ]] && bindkey "${key[Right]}" forward-char
# etc.
Note that in order for ‘autoload zkbd’ to work, the zkdb file must be
in one of the directories named in your fpath array (see zshparam(1)).
This should already be the case if you have a standard zsh installa-
tion; if it is not, copy Functions/Misc/zkbd to an appropriate direc-
tory.
Dumping Shell State
Occasionally you may encounter what appears to be a bug in the shell,
particularly if you are using a beta version of zsh or a development
release. Usually it is sufficient to send a description of the prob-
lem to one of the zsh mailing lists (see zsh(1)), but sometimes one of
the zsh developers will need to recreate your environment in order to
track the problem down.
The script named reporter, found in the Util directory of the distri-
bution, is provided for this purpose. (It is also possible to
autoload reporter, but reporter is not installed in fpath by default.)
This script outputs a detailed dump of the shell state, in the form of
another script that can be read with ‘zsh -f’ to recreate that state.
To use reporter, read the script into your shell with the ‘.’ command
and redirect the output into a file:
. ~/zsh-4.2.0/Util/reporter > zsh.report
You should check the zsh.report file for any sensitive information
such as passwords and delete them by hand before sending the script to
the developers. Also, as the output can be voluminous, it’s best to
wait for the developers to ask for this information before sending it.
You can also use reporter to dump only a subset of the shell state.
This is sometimes useful for creating startup files for the first
time. Most of the output from reporter is far more detailed than usu-
ally is necessary for a startup file, but the aliases, options, and
zstyles states may be useful because they include only changes from
the defaults. The bindings state may be useful if you have created
any of your own keymaps, because reporter arranges to dump the keymap
creation commands as well as the bindings for every keymap.
As is usual with automated tools, if you create a startup file with
reporter, you should edit the results to remove unnecessary commands.
Note that if you’re using the new completion system, you should not
dump the functions state to your startup files with reporter; use the
compdump function instead (see zshcompsys(1)).
reporter [ state ... ]
Print to standard output the indicated subset of the current
shell state. The state arguments may be one or more of:
all Output everything listed below.
aliases
Output alias definitions.
bindings
Output ZLE key maps and bindings.
completion
Output old-style compctl commands. New completion is
covered by functions and zstyles.
functions
Output autoloads and function definitions.
limits Output limit commands.
options
Output setopt commands.
styles Same as zstyles.
variables
Output shell parameter assignments, plus export commands
for any environment variables.
zstyles
Output zstyle commands.
If the state is omitted, all is assumed.
With the exception of ‘all’, every state can be abbreviated by any
prefix, even a single letter; thus a is the same as aliases, z is the
same as zstyles, etc.
PROMPT THEMES
Installation
You should make sure all the functions from the Functions/Prompts
directory of the source distribution are available; they all begin
with the string ‘prompt_’ except for the special function‘promptinit’.
You also need the ‘colors’ function from Functions/Misc. All of these
functions may already have been installed on your system; if not, you
will need to find them and copy them. The directory should appear as
one of the elements of the fpath array (this should already be the
case if they were installed), and at least the function promptinit
should be autoloaded; it will autoload the rest. Finally, to initial-
ize the use of the system you need to call the promptinit function.
The following code in your .zshrc will arrange for this; assume the
functions are stored in the directory ~/myfns:
fpath=(~/myfns $fpath)
autoload -U promptinit
promptinit
Theme Selection
Use the prompt command to select your preferred theme. This command
may be added to your .zshrc following the call to promptinit in order
to start zsh with a theme already selected.
prompt [ -c | -l ]
prompt [ -p | -h ] [ theme ... ]
prompt [ -s ] theme [ arg ... ]
Set or examine the prompt theme. With no options and a theme
argument, the theme with that name is set as the current theme.
The available themes are determined at run time; use the -l
option to see a list. The special theme ‘random’ selects at
random one of the available themes and sets your prompt to
that.
In some cases the theme may be modified by one or more argu-
ments, which should be given after the theme name. See the
help for each theme for descriptions of these arguments.
Options are:
-c Show the currently selected theme and its parameters, if
any.
-l List all available prompt themes.
-p Preview the theme named by theme, or all themes if no
theme is given.
-h Show help for the theme named by theme, or for the
prompt function if no theme is given.
-s Set theme as the current theme and save state.
prompt_theme_setup
Each available theme has a setup function which is called by
the prompt function to install that theme. This function may
define other functions as necessary to maintain the prompt,
including functions used to preview the prompt or provide help
for its use. You should not normally call a theme’s setup
function directly.
ZLE FUNCTIONS
Widgets
These functions all implement user-defined ZLE widgets (see zshzle(1))
which can be bound to keystrokes in interactive shells. To use them,
your .zshrc should contain lines of the form
autoload function
zle -N function
followed by an appropriate bindkey command to associate the function
with a key sequence. Suggested bindings are described below.
bash-style word functions
If you are looking for functions to implement moving over and
editing words in the manner of bash, where only alphanumeric
characters are considered word characters, you can use the
functions described in the next section. The following is suf-
ficient:
autoload -U select-word-style
select-word-style bash
forward-word-match, backward-word-match
kill-word-match, backward-kill-word-match
transpose-words-match, capitalize-word-match
up-case-word-match, down-case-word-match
select-word-style, match-words-by-style
The eight ‘-match’ functions are drop-in replacements for the
builtin widgets without the suffix. By default they behave in
a similar way. However, by the use of styles and the function
select-word-style, the way words are matched can be altered.
The simplest way of configuring the functions is to use
select-word-style, which can either be called as a normal func-
tion with the appropriate argument, or invoked as a
user-defined widget that will prompt for the first character of
the word style to be used. The first time it is invoked, the
eight -match functions will automatically replace the builtin
versions, so they do not need to be loaded explicitly.
The word styles available are as follows. Only the first char-
acter is examined.
bash Word characters are alphanumeric characters only.
normal As in normal shell operation: word characters are
alphanumeric characters plus any characters present in
the string given by the parameter $WORDCHARS.
shell Words are complete shell command arguments, possibly
including complete quoted strings, or any tokens special
to the shell.
whitespace
Words are any set of characters delimited by whitespace.
default
Restore the default settings; this is usually the same
as ‘normal’.
More control can be obtained using the zstyle command, as
described in zshmodules(1). Each style is looked up in the
context :zle:widget where widget is the name of the
user-defined widget, not the name of the function implementing
it, so in the case of the definitions supplied by
select-word-style the appropriate contexts are :zle:for-
ward-word, and so on. The function select-word-style itself
always defines styles for the context ‘:zle:*’ which can be
overridden by more specific (longer) patterns as well as
explicit contexts.
The style word-style specifies the rules to use. This may have
the following values.
normal Use the standard shell rules, i.e. alphanumerics and
$WORDCHARS, unless overridden by the styles word-chars
or word-class.
specified
Similar to normal, but only the specified characters,
and not also alphanumerics, are considered word charac-
ters.
unspecified
The negation of specified. The given characters are
those which will not be considered part of a word.
shell Words are obtained by using the syntactic rules for gen-
erating shell command arguments. In addition, special
tokens which are never command arguments such as ‘()’
are also treated as words.
whitespace
Words are whitespace-delimited strings of characters.
The first three of those styles usually use $WORDCHARS, but the
value in the parameter can be overridden by the style
word-chars, which works in exactly the same way as $WORDCHARS.
In addition, the style word-class uses character class syntax
to group characters and takes precedence over word-chars if
both are set. The word-class style does not include the sur-
rounding brackets of the character class; for example,
‘-:[:alnum:]’ is a valid word-class to include all alphanumer-
ics plus the characters ‘-’ and ‘:’. Be careful including ‘]’,
‘^’ and ‘-’ as these are special inside character classes.
The final style is skip-chars. This is mostly useful for
transpose-words and similar functions. If set, it gives a
count of characters starting at the cursor position which will
not be considered part of the word and are treated as space,
regardless of what they actually are. For example, if
zstyle ’:zle:transpose-words’ skip-chars 1
has been set, and transpose-words-match is called with the cur-
sor on the X of fooXbar, where X can be any character, then the
resulting expression is barXfoo.
Here are some examples of use of the styles, actually taken
from the simplified interface in select-word-style:
zstyle ’:zle:*’ word-style standard
zstyle ’:zle:*’ word-chars ’’
Implements bash-style word handling for all widgets, i.e. only
alphanumerics are word characters; equivalent to setting the
parameter WORDCHARS empty for the given context.
style ’:zle:*kill*’ word-style space
Uses space-delimited words for widgets with the word ‘kill’ in
the name. Neither of the styles word-chars nor word-class is
used in this case.
The word matching and all the handling of zstyle settings is
actually implemented by the function match-words-by-style.
This can be used to create new user-defined widgets. The call-
ing function should set the local parameter curcontext to
:zle:widget, create the local parameter matched_words and call
match-words-by-style with no arguments. On return,
matched_words will be set to an array with the elements: (1)
the start of the line (2) the word before the cursor (3) any
non-word characters between that word and the cursor (4) any
non-word character at the cursor position plus any remaining
non-word characters before the next word, including all charac-
ters specified by the skip-chars style, (5) the word at or fol-
lowing the cursor (6) any non-word characters following that
word (7) the remainder of the line. Any of the elements may be
an empty string; the calling function should test for this to
decide whether it can perform its function.
delete-whole-word-match
This is another function which works like the -match functions
described immediately above, i.e. using styles to decide the
word boundaries. However, it is not a replacement for any
existing function.
The basic behaviour is to delete the word around the cursor.
There is no numeric prefix handling; only the single word
around the cursor is considered. If the widget contains the
string kill, the removed text will be placed in the cutbuffer
for future yanking. This can be obtained by defining
kill-whole-word-match as follows:
zle -N kill-whole-word-match delete-whole-word-match
and then binding the widget kill-whole-word-match.
copy-earlier-word
This widget works like a combination of insert-last-word and
copy-prev-shell-word. Repeated invocations of the widget
retrieve earlier words on the relevant history line. With a
numeric argument N, insert the Nth word from the history line;
N may be negative to count from the end of the line.
If insert-last-word has been used to retrieve the last word on
a previous history line, repeated invocations will replace that
word with earlier words from the same line.
Otherwise, the widget applies to words on the line currently
being edited. The widget style can be set to the name of
another widget that should be called to retrieve words. This
widget must accept the same three arguments as
insert-last-word.
cycle-completion-positions
After inserting an unambiguous string into the command line,
the new function based completion system may know about multi-
ple places in this string where characters are missing or dif-
fer from at least one of the possible matches. It will then
place the cursor on the position it considers to be the most
interesting one, i.e. the one where one can disambiguate
between as many matches as possible with as little typing as
possible.
This widget allows the cursor to be easily moved to the other
interesting spots. It can be invoked repeatedly to cycle
between all positions reported by the completion system.
edit-command-line
Edit the command line using your visual editor, as in ksh.
bindkey -M vicmd v edit-command-line
history-search-end
This function implements the widgets history-begin-
ning-search-backward-end and history-beginning-search-for-
ward-end. These commands work by first calling the correspond-
ing builtin widget (see ‘History Control’ in zshzle(1)) and
then moving the cursor to the end of the line. The original
cursor position is remembered and restored before calling the
builtin widget a second time, so that the same search is
repeated to look farther through the history.
Although you autoload only one function, the commands to use it
are slightly different because it implements two widgets.
zle -N history-beginning-search-backward-end \
history-search-end
zle -N history-beginning-search-forward-end \
history-search-end
bindkey ’\e^P’ history-beginning-search-backward-end
bindkey ’\e^N’ history-beginning-search-forward-end
up-line-or-beginning-search, down-line-or-beginning-search
These widgets are similar to the builtin functions
up-line-or-search and down-line-or-search: if in a multiline
buffer they move up or down within the buffer, otherwise they
search for a history line matching the start of the current
line. In this case, however, they search for a line which
matches the current line up to the current cursor position, in
the manner of history-beginning-search-backward and -forward,
rather than the first word on the line.
incarg Typing the keystrokes for this widget with the cursor placed on
or to the left of an integer causes that integer to be incre-
mented by one. With a numeric prefix argument, the number is
incremented by the amount of the argument (decremented if the
prefix argument is negative). The shell parameter incarg may
be set to change the default increment something other than
one.
bindkey ’^X+’ incarg
incremental-complete-word
This allows incremental completion of a word. After starting
this command, a list of completion choices can be shown after
every character you type, which you can delete with ^H or DEL.
Pressing return accepts the completion so far and returns you
to normal editing (that is, the command line is not immediately
executed). You can hit TAB to do normal completion, ^G to
abort back to the state when you started, and ^D to list the
matches.
This works only with the new function based completion system.
bindkey ’^Xi’ incremental-complete-word
insert-files
This function allows you type a file pattern, and see the
results of the expansion at each step. When you hit return,
all expansions are inserted into the command line.
bindkey ’^Xf’ insert-files
narrow-to-region [ -p pre ] [ -P post ]
[ -S statepm | -R statepm ] [ -n ] [ start end ])
narrow-to-region-invisible
Narrow the editable portion of the buffer to the region between
the cursor and the mark, which may be in either order. The
region may not be empty.
narrow-to-region may be used as a widget or called as a
function from a user-defined widget; by default, the text out-
side the editable area remains visible. A recursive-edit is
performed and the original widening status is then restored.
Various options and arguments are available when it is called
as a function.
The options -p pretext and -P posttext may be used to replace
the text before and after the display for the duration of the
function; either or both may be an empty string.
If the option -n is also given, pretext or posttext will only
be inserted if there is text before or after the region respec-
tively which will be made invisible.
Two numeric arguments may be given which will be used instead
of the cursor and mark positions.
The option -S statepm is used to narrow according to the other
options while saving the original state in the parameter with
name statepm, while the option -R statepm is used to restore
the state from the parameter; note in both cases the name of
the parameter is required. In the second case, other options
and arguments are irrelevant. When this method is used, no
recursive-edit is performed; the calling widget should call
this function with the option -S, perform its own editing on
the command line or pass control to the user via ‘zle recur-
sive-edit’, then call this function with the option -R. The
argument statepm must be a suitable name for an ordinary param-
eter, except that parameters beginning with the prefix _ntr_
are reserved for use within narrow-to-region. Typically the
parameter will be local to the calling function.
narrow-to-region-invisible is a simple widget which calls nar-
row-to-region with arguments which replace any text outside the
region with ‘...’.
The display is restored (and the widget returns) upon any zle
command which would usually cause the line to be accepted or
aborted. Hence an additional such command is required to
accept or abort the current line.
The return status of both widgets is zero if the line was
accepted, else non-zero.
Here is a trivial example of a widget using this feature.
local state
narrow-to-region -p $’Editing restricted region\n’ \
-P ’’ -S state
zle recursive-edit
narrow-to-region -R state
predict-on
This set of functions implements predictive typing using his-
tory search. After predict-on, typing characters causes the
editor to look backward in the history for the first line
beginning with what you have typed so far. After predict-off,
editing returns to normal for the line found. In fact, you
often don’t even need to use predict-off, because if the line
doesn’t match something in the history, adding a key performs
standard completion, and then inserts itself if no completions
were found. However, editing in the middle of a line is liable
to confuse prediction; see the toggle style below.
With the function based completion system (which is needed for
this), you should be able to type TAB at almost any point to
advance the cursor to the next ‘‘interesting’’ character posi-
tion (usually the end of the current word, but sometimes some-
where in the middle of the word). And of course as soon as the
entire line is what you want, you can accept with return, with-
out needing to move the cursor to the end first.
The first time predict-on is used, it creates several addi-
tional widget functions:
delete-backward-and-predict
Replaces the backward-delete-char widget. You do not
need to bind this yourself.
insert-and-predict
Implements predictive typing by replacing the
self-insert widget. You do not need to bind this your-
self.
predict-off
Turns off predictive typing.
Although you autoload only the predict-on function, it is nec-
essary to create a keybinding for predict-off as well.
zle -N predict-on
zle -N predict-off
bindkey ’^X^Z’ predict-on
bindkey ’^Z’ predict-off
read-from-minibuffer
This is most useful when called as a function from inside a
widget, but will work correctly as a widget in its own right.
It prompts for a value below the current command line; a value
may be input using all of the standard zle operations (and not
merely the restricted set available when executing, for exam-
ple, execute-named-cmd). The value is then returned to the
calling function in the parameter $REPLY and the editing buffer
restored to its previous state. If the read was aborted by a
keyboard break (typically ^G), the function returns status 1
and $REPLY is not set. If an argument is supplied to the func-
tion it is taken as a prompt, otherwise ‘? ’ is used.
One option is available: ‘-k num’ specifies that num characters
are to be read instead of a whole line. The line editor is not
invoked recursively in this case. Note that unlike the read
builtin num must be given; there is no default.
The name is a slight misnomer, as in fact the shell’s own
minibuffer is not used. Hence it is still possible to call
executed-named-cmd and similar functions while reading a value.
replace-string, replace-pattern
The function replace-string implements two widgets. If defined
under the same name as the function, it prompts for two
strings; the first (source) string will be replaced by the sec-
ond everywhere it occurs in the line editing buffer.
If the widget name contains the word ‘pattern’, for example by
defining the widget using the command ‘zle -N replace-pattern
replace-string’, then the replacement is done by pattern match-
ing. All zsh extended globbing patterns can be used in the
source string; note that unlike filename generation the pattern
does not need to match an entire word, nor do glob qualifiers
have any effect. In addition, the replacement string can con-
tain parameter or command substitutions. Furthermore, a ‘&’ in
the replacement string will be replaced with the matched source
string, and a backquoted digit ‘\N’ will be replaced by the Nth
parenthesised expression matched. The form ‘\{N}’ may be used
to protect the digit from following digits.
For example, starting from the line:
print This line contains fan and fond
and invoking replace-pattern with the source string ‘f(?)n’ and
the replacment string ‘c\1r’ produces the not very useful line:
print This line contains car and cord
The range of the replacement string can be limited by using the
narrow-to-region-invisible widget. One limitation of the cur-
rent version is that undo will cycle through changes to the
replacement and source strings before undoing the replacement
itself.
smart-insert-last-word
This function may replace the insert-last-word widget, like so:
zle -N insert-last-word smart-insert-last-word
With a numeric prefix, or when passed command line arguments in
a call from another widget, it behaves like insert-last-word,
except that words in comments are ignored when INTERACTIVE_COM-
MENTS is set.
Otherwise, the rightmost ‘‘interesting’’ word from the previous
command is found and inserted. The default definition of
‘‘interesting’’ is that the word contains at least one alpha-
betic character, slash, or backslash. This definition may be
overridden by use of the match style. The context used to look
up the style is the widget name, so usually the context is
:insert-last-word. However, you can bind this function to dif-
ferent widgets to use different patterns:
zle -N insert-last-assignment smart-insert-last-word
zstyle :insert-last-assignment match ’[[:alpha:]][][[:alnum:]]#=*’
bindkey ’\e=’ insert-last-assignment
Styles
The behavior of several of the above widgets can be controlled by the
use of the zstyle mechanism. In particular, widgets that interact
with the completion system pass along their context to any completions
that they invoke.
break-keys
This style is used by the incremental-complete-word widget. Its
value should be a pattern, and all keys matching this pattern
will cause the widget to stop incremental completion without
the key having any further effect. Like all styles used
directly by incremental-complete-word, this style is looked up
using the context ‘:incremental’.
completer
The incremental-complete-word and insert-and-predict widgets
set up their top-level context name before calling completion.
This allows one to define different sets of completer functions
for normal completion and for these widgets. For example, to
use completion, approximation and correction for normal comple-
tion, completion and correction for incremental completion and
only completion for prediction one could use:
zstyle ’:completion:*’ completer \
_complete _correct _approximate
zstyle ’:completion:incremental:*’ completer \
_complete _correct
zstyle ’:completion:predict:*’ completer \
_complete
It is a good idea to restrict the completers used in predic-
tion, because they may be automatically invoked as you type.
The _list and _menu completers should never be used with pre-
diction. The _approximate, _correct, _expand, and _match com-
pleters may be used, but be aware that they may change charac-
ters anywhere in the word behind the cursor, so you need to
watch carefully that the result is what you intended.
cursor The insert-and-predict widget uses this style, in the context
‘:predict’, to decide where to place the cursor after comple-
tion has been tried. Values are:
complete
The cursor is left where it was when completion fin-
ished, but only if it is after a character equal to the
one just inserted by the user. If it is after another
character, this value is the same as ‘key’.
key The cursor is left after the nth occurrence of the char-
acter just inserted, where n is the number of times that
character appeared in the word before completion was
attempted. In short, this has the effect of leaving the
cursor after the character just typed even if the com-
pletion code found out that no other characters need to
be inserted at that position.
Any other value for this style unconditionally leaves the cur-
sor at the position where the completion code left it.
list When using the incremental-complete-word widget, this style
says if the matches should be listed on every key press (if
they fit on the screen). Use the context prefix ‘:comple-
tion:incremental’.
The insert-and-predict widget uses this style to decide if the
completion should be shown even if there is only one possible
completion. This is done if the value of this style is the
string always. In this case the context is ‘:predict’ (not
‘:completion:predict’).
match This style is used by smart-insert-last-word to provide a pat-
tern (using full EXTENDED_GLOB syntax) that matches an inter-
esting word. The context is the name of the widget to which
smart-insert-last-word is bound (see above). The default
behavior of smart-insert-last-word is equivalent to:
zstyle :insert-last-word match ’*[[:alpha:]/\\]*’
However, you might want to include words that contain spaces:
zstyle :insert-last-word match ’*[[:alpha:][:space:]/\\]*’
Or include numbers as long as the word is at least two charac-
ters long:
zstyle :insert-last-word match ’*([[:digit:]]?|[[:alpha:]/\\])*’
The above example causes redirections like "2>" to be included.
prompt The incremental-complete-word widget shows the value of this
style in the status line during incremental completion. The
string value may contain any of the following substrings in the
manner of the PS1 and other prompt parameters:
%c Replaced by the name of the completer function that gen-
erated the matches (without the leading underscore).
%l When the list style is set, replaced by ‘...’ if the
list of matches is too long to fit on the screen and
with an empty string otherwise. If the list style is
‘false’ or not set, ‘%l’ is always removed.
%n Replaced by the number of matches generated.
%s Replaced by ‘-no match-’, ‘-no prefix-’, or an empty
string if there is no completion matching the word on
the line, if the matches have no common prefix different
from the word on the line, or if there is such a common
prefix, respectively.
%u Replaced by the unambiguous part of all matches, if
there is any, and if it is different from the word on
the line.
Like ‘break-keys’, this uses the ‘:incremental’ context.
stop-keys
This style is used by the incremental-complete-word widget.
Its value is treated similarly to the one for the break-keys
style (and uses the same context: ‘:incremental’). However, in
this case all keys matching the pattern given as its value will
stop incremental completion and will then execute their usual
function.
toggle This boolean style is used by predict-on and its related wid-
gets in the context ‘:predict’. If set to one of the standard
‘true’ values, predictive typing is automatically toggled off
in situations where it is unlikely to be useful, such as when
editing a multi-line buffer or after moving into the middle of
a line and then deleting a character. The default is to leave
prediction turned on until an explicit call to predict-off.
verbose
This boolean style is used by predict-on and its related wid-
gets in the context ‘:predict’. If set to one of the standard
‘true’ values, these widgets display a message below the prompt
when the predictive state is toggled. This is most useful in
combination with the toggle style. The default does not dis-
play these messages.
widget This style is similar to the command style: For widget func-
tions that use zle to call other widgets, this style can some-
times be used to override the widget which is called. The con-
text for this style is the name of the calling widget (not the
name of the calling function, because one function may be bound
to multiple widget names).
zstyle :copy-earlier-word widget smart-insert-last-word
Check the documentation for the calling widget or function to
determine whether the widget style is used.
MIME FUNCTIONS
Three functions are available to provide handling of files recognised
by extension, for example to dispatch a file text.ps when executed as
a command to an appropriate viewer.
zsh-mime-setup [-flv]
zsh-mime-handler
These two functions use the files ~/.mime.types and
/etc/mime.types, which associate types and extensions, as well
as ~/.mailcap and /etc/mailcap files, which associate types and
the programs that handle them. These are provided on many sys-
tems with the Multimedia Internet Mail Extensions.
To enable the system, the function zsh-mime-setup should be
autoloaded and run. This allows files with extensions to be
treated as executable; such files be completed by the function
completion system. The function zsh-mime-handler should not
need to be called by the user.
The system works by setting up suffix aliases with ‘alias -s’.
Suffix aliases already installed by the user will not be over-
written.
Repeated calls to zsh-mime-setup do not override the existing
mapping between suffixes and executable files unless the option
-f is given. Note, however, that this does not override exist-
ing suffix aliases assigned to handlers other than
zsh-mime-handler. Calling zsh-mime-setup with the option -l
lists the existing mapping without altering it. Calling
zsh-mime-setup with the option -v causes verbose output to be
shown during the setup operation.
The system respects the mailcap flags needsterminal and copi-
ousoutput, see mailcap(4).
The functions use the following styles, which are defined with
the zstyle builtin command (see zshmodules(1)). They should be
defined before zsh-mime-setup is run. The contexts used all
start with :mime:, with additional components in some cases.
It is recommended that a trailing * (suitably quoted) be
appended to style patterns in case the system is extended in
future. Some examples are given below.
mime-types
A list of files in the format of ~/.mime.types and
/etc/mime.types to be read during setup, replacing the
default list which consists of those two files. The
context is :mime:.
mailcap
A list of files in the format of ~/.mailcap and
/etc/mailcap to be read during setup, replacing the
default list which consists of those two files. The
context is :mime:.
handler
Specifies a handler for a suffix; the suffix is given by
the context as :mime:.suffix:, and the format of the
handler is exactly that in mailcap. Note in particular
the ‘.’ and trailing colon to distinguish this use of
the context. This overrides any handler specified by
the mailcap files. If the handler requires a terminal,
the flags style should be set to include the word need-
sterminal, or if the output is to be displayed through a
pager (but not if the handler is itself a pager), it
should include copiousoutput.
flags Defines flags to go with a handler; the context is as
for the handler style, and the format is as for the
flags in mailcap.
pager If set, will be used instead of $PAGER or more to handle
suffixes where the copiousoutput flag is set. The con-
text is as for handler, i.e. :mime:.suffix: for handling
a file with the given suffix.
Examples:
zstyle ’:mime:*’ mailcap ~/.mailcap /usr/local/etc/mailcap
zstyle ’:mime:.txt’ handler less %s
zstyle ’:mime:.txt’ flags needsterminal
When zsh-mime-setup is subsequently run, it will look for mail-
cap entries in the two files given. Files of suffix .txt will
be handled by running ‘less file.txt’. The flag needsterminal
is set to show that this program must run attached to a termi-
nal.
As there are several steps to dispatching a command, the fol-
lowing should be checked if attempting to execute a file by
extension .ext does not have the expected effect. starteit()
eit()( The command ‘alias -s ext’ should show ‘ps=zsh-mime-han-
dler’. If it shows something else, another suffix alias was
already installed and was not overwritten. If it shows noth-
ing, no handler was installed: this is most likely because no
handler was found in the .mime.types and mailcap combination
for .ext files. In that case, appropriate handling should be
added to ~/.mime.types and mailcap. ) eit()( If the extension
is handled by zsh-mime-handler but the file is not opened cor-
rectly, either the handler defined for the type is incorrect,
or the flags associated with it are in appropriate. Running
zsh-mime-setup -l will show the handler and, if there are any,
the flags. A %s in the handler is replaced by the file (suit-
ably quoted if necessary). Check that the handler program
listed lists and can be run in the way shown. Also check that
the flags needsterminal or copiousoutput are set if the handler
needs to be run under a terminal; the second flag is used if
the output should be sent to a pager. An example of a suitable
mailcap entry for such a program is:
text/html; /usr/bin/lynx ’%s’; needsterminal
) endeit()
pick-web-browser
This function is separate from the two MIME functions described
above and can be assigned directly to a suffix:
autoload -U pick-web-browser
alias -s html=pick-web-browser
It is provided as an intelligent front end to dispatch a web
browser. It will check if an X Windows display is available,
and if so if there is already a browser running which can
accept a remote connection. In that case, the file will be
displayed in that browser; you should check explicitly if it
has appeared in the running browser’s window. Otherwise, it
will start a new browser according to a builtin set of prefer-
ences.
Alternatively, pick-web-browser can be run as a zsh script.
Two styles are available to customize the choice of browsers:
x-browsers when running under the X Windows System, and
tty-browsers otherwise. These are arrays in decreasing order
of preference consiting of the command name under which to
start the browser. They are looked up in the context :mime:
(which may be extended in future, so appending ‘*’ is recom-
mended). For example,
zstyle ’:mime:*’ x-browsers opera konqueror netscape
specifies that pick-web-browser should first look for a runing
instance of Opera, Konqueror or Netscape, in that order, and if
it fails to find any should attempt to start Opera.
OTHER FUNCTIONS
There are a large number of helpful functions in the Functions/Misc
directory of the zsh distribution. Most are very simple and do not
require documentation here, but a few are worthy of special mention.
Descriptions
colors This function initializes several associative arrays to map
color names to (and from) the ANSI standard eight-color termi-
nal codes. These are used by the prompt theme system (see
above). You seldom should need to run colors more than once.
The eight base colors are: black, red, green, yellow, blue,
magenta, cyan, and white. Each of these has codes for fore-
ground and background. In addition there are eight intensity
attributes: bold, faint, standout, underline, blink, reverse,
and conceal. Finally, there are six codes used to negate
attributes: none (reset all attributes to the defaults), normal
(neither bold nor faint), no-standout, no-underline, no-blink,
and no-reverse.
Some terminals do not support all combinations of colors and
intensities.
The associative arrays are:
color
colour Map all the color names to their integer codes, and
integer codes to the color names. The eight base names
map to the foreground color codes, as do names prefixed
with ‘fg-’, such as ‘fg-red’. Names prefixed with
‘bg-’, such as ‘bg-blue’, refer to the background codes.
The reverse mapping from code to color yields base name
for foreground codes and the bg- form for backgrounds.
Although it is a misnomer to call them ‘colors’, these
arrays also map the other fourteen attributes from names
to codes and codes to names.
fg
fg_bold
fg_no_bold
Map the eight basic color names to ANSI terminal escape
sequences that set the corresponding foreground text
properties. The fg sequences change the color without
changing the eight intensity attributes.
bg
bg_bold
bg_no_bold
Map the eight basic color names to ANSI terminal escape
sequences that set the corresponding background proper-
ties. The bg sequences change the color without chang-
ing the eight intensity attributes.
In addition, the scalar parameters reset_color and bold_color
are set to the ANSI terminal escapes that turn off all
attributes and turn on bold intensity, respectively.
fned name
Same as zed -f. This function does not appear in the zsh dis-
tribution, but can be created by linking zed to the name fned
in some directory in your fpath.
is-at-least needed [ present ]
Perform a greater-than-or-equal-to comparison of two strings
having the format of a zsh version number; that is, a string of
numbers and text with segments separated by dots or dashes. If
the present string is not provided, $ZSH_VERSION is used. Seg-
ments are paired left-to-right in the two strings with leading
non-number parts ignored. If one string has fewer segments
than the other, the missing segments are considered zero.
This is useful in startup files to set options and other state
that are not available in all versions of zsh.
is-at-least 3.1.6-15 && setopt NO_GLOBAL_RCS
is-at-least 3.1.0 && setopt HIST_REDUCE_BLANKS
is-at-least 2.6-17 || print "You can’t use is-at-least here."
nslookup [ arg ... ]
This wrapper function for the nslookup command requires the
zsh/zpty module (see zshmodules(1)). It behaves exactly like
the standard nslookup except that it provides customizable
prompts (including a right-side prompt) and completion of
nslookup commands, host names, etc. (if you use the func-
tion-based completion system). Completion styles may be set
with the context prefix ‘:completion:nslookup’.
See also the pager, prompt and rprompt styles below.
run-help
See ‘Accessing On-Line Help’ above.
tetris Zsh was once accused of not being as complete as Emacs, because
it lacked a Tetris game. This function was written to refute
this vicious slander.
This function must be used as a ZLE widget:
autoload -U tetris
zle -N tetris
bindkey keys tetris
To start a game, execute the widget by typing the keys. What-
ever command line you were editing disappears temporarily, and
your keymap is also temporarily replaced by the Tetris control
keys. The previous editor state is restored when you quit the
game (by pressing ‘q’) or when you lose.
If you quit in the middle of a game, the next invocation of the
tetris widget will continue where you left off. If you lost,
it will start a new game.
zcalc [ expression ... ]
A reasonably powerful calculator based on zsh’s arithmetic
evaluation facility. The syntax is similar to that of formulae
in most programming languages; see the section ‘Arithmetic
Evaluation’ in zshmisc(1) for details. The mathematical
library zsh/mathfunc will be loaded if it is available; see the
section ‘The zsh/mathfunc Module’ in zshmodules(1). The mathe-
matical functions correspond to the raw system libraries, so
trigonometric functions are evaluated using radians, and so on.
Each line typed is evaluated as an expression. The prompt
shows a number, which corresponds to a positional parameter
where the result of that calculation is stored. For example,
the result of the calculation on the line preceded by ‘4> ’ is
available as $4. Full command line editing, including the his-
tory of previous calculations, is available; the history is
saved in the file ~/.zcalc_history. To exit, enter a blank
line or type ‘q’ on its own.
If arguments are given to zcalc on start up, they are used to
prime the first few positional parameters. A visual indication
of this is given when the calculator starts.
The constants PI (3.14159...) and E (2.71828...) are provided.
Parameter assignment is possible, but note that all parameters
will be put into the global namespace.
An extra facility is provided for changing the default output
base. Use, for example, ‘[#16]’ to display hexadecimal output
preceded by an indication of the base, or ‘[##16]’ just to dis-
play the raw number in the given base. Bases themselves are
always specified in decimal. ‘[#]’ restores the normal output
format.
The output base can be initialised by passing the option
‘-#base’, for example ‘zcalc -#16’ (the ‘#’ may have to be
quoted, depending on the globbing options set).
The prompt is configurable via the parameter ZCALCPROMPT, which
undergoes standard prompt expansion. The index of the current
entry is stored locally in the first element of the array
psvar, which can be referred to in ZCALCPROMPT as ‘%1v’. The
default prompt is ‘%1v> ’.
See the comments in the function for a few extra tips.
zed [ -f ] name
This function uses the ZLE editor to edit a file or function.
It rebinds the return key to insert a line break, and adds
bindings for ‘^X^W’ in the emacs keymap and ‘ZZ’ in the vicmd
keymap to accept (and therefore write, in the case of a file)
the edited file or function. Keybindings are otherwise the
standard ones; completion is available, and styles may be set
with the context prefix ‘:completion:zed’.
Only one name argument is recognized (additional arguments are
ignored). If the -f option is given, the name is taken to be
that of a function; if the function is marked for autoloading,
zed searches for it in the fpath and loads it. Note that func-
tions edited this way are installed into the current shell, but
not written back to the autoload file.
Without -f, name is the path name of the file to edit, which
need not exist; it is created on write, if necessary.
zcp [ -finqQvwW ] srcpat dest
zln [ -finqQsvwW ] srcpat dest
Same as zmv -C and zmv -L, respectively. These functions do
not appear in the zsh distribution, but can be created by link-
ing zmv to the names zcp and zln in some directory in your
fpath.
zkbd See ‘Keyboard Definition’ above.
zmv [ -finqQsvwW ] [ -C | -L | -M | -p program ] [ -o optstring ] src-
pat dest
Move (usually, rename) files matching the pattern srcpat to
corresponding files having names of the form given by dest,
where srcpat contains parentheses surrounding patterns which
will be replaced in turn by $1, $2, ... in dest. For example,
zmv ’(*).lis’ ’$1.txt’
renames ‘foo.lis’ to ‘foo.txt’, ‘my.old.stuff.lis’ to
‘my.old.stuff.txt’, and so on.
The pattern is always treated as an EXTENDED_GLOB pattern. Any
file whose name is not changed by the substitution is simply
ignored. Any error (a substitution resulted in an empty
string, two substitutions gave the same result, the destination
was an existing regular file and -f was not given) causes the
entire function to abort without doing anything.
Options:
-f Force overwriting of destination files. Not currently
passed down to the mv/cp/ln command due to vagaries of
implementations (but you can use -o-f to do that).
-i Interactive: show each line to be executed and ask the
user whether to execute it. ‘Y’ or ‘y’ will execute it,
anything else will skip it. Note that you just need to
type one character.
-n No execution: print what would happen, but don’t do it.
-q Turn bare glob qualifiers off: now assumed by default,
so this has no effect.
-Q Force bare glob qualifiers on. Don’t turn this on
unless you are actually using glob qualifiers in a pat-
tern.
-s Symbolic, passed down to ln; only works with -L.
-v Verbose: print each command as it’s being executed.
-w Pick out wildcard parts of the pattern, as described
above, and implicitly add parentheses for referring to
them.
-W Just like -w, with the addition of turning wildcards in
the replacement pattern into sequential ${1} .. ${N}
references.
-C
-L
-M Force cp, ln or mv, respectively, regardless of the name
of the function.
-p program
Call program instead of cp, ln or mv. Whatever it does,
it should at least understand the form ‘program -- old-
name newname’ where oldname and newname are filenames
generated by zmv.
-o optstring
The optstring is split into words and passed down verba-
tim to the cp, ln or mv command called to perform the
work. It should probably begin with a ‘-’.
For more complete examples and other implementation details,
see the zmv source file, usually located in one of the directo-
ries named in your fpath, or in Functions/Misc/zmv in the zsh
distribution.
zrecompile
See ‘Recompiling Functions’ above.
zstyle+ context style value [ + subcontext style value ... ]
This makes defining styles a bit simpler by using a single ‘+’
as a special token that allows you to append a context name to
the previously used context name. Like this:
zstyle+ ’:foo:bar’ style1 value1 \
+ ’:baz’ style2 value2 \
+ ’:frob’ style3 value3
This defines ‘style1’ with ‘value1’ for the context :foo:bar as
usual, but it also defines ‘style2’ with ‘value2’ for the con-
text :foo:bar:baz and ‘style3’ with ‘value3’ for :foo:bar:frob.
Any subcontext may be the empty string to re-use the first con-
text unchanged.
Styles
insert-tab
The zed function sets this style in context ‘:completion:zed:*’
to turn off completion when TAB is typed at the beginning of a
line. You may override this by setting your own value for this
context and style.
pager The nslookup function looks up this style in the context
‘:nslookup’ to determine the program used to display output
that does not fit on a single screen.
prompt
rprompt
The nslookup function looks up this style in the context
‘:nslookup’ to set the prompt and the right-side prompt,
respectively. The usual expansions for the PS1 and RPS1 param-
ZSHALL(1) ZSHALL(1)
eters may be used (see zshmisc(1)).
FILES
$ZDOTDIR/.zshenv
$ZDOTDIR/.zprofile
$ZDOTDIR/.zshrc
$ZDOTDIR/.zlogin
$ZDOTDIR/.zlogout
${TMPPREFIX}* (default is /tmp/zsh*)
/etc/zshenv
/etc/zprofile
/etc/zshrc
/etc/zlogin
/etc/zlogout (installation-specific - /etc is the default)
SEE ALSO
sh(1), csh(1), tcsh(1), rc(1), bash(1), ksh(1)
IEEE Standard for information Technology - Portable Operating System
Interface (POSIX) - Part 2: Shell and Utilities, IEEE Inc, 1993, ISBN
1-55937-255-9.
zsh 4.2.0 March 19, 2004 ZSHALL(1)
