hier
HIER(7) Linux Programmer’s Manual HIER(7)
NAME
hier - Description of the file system hierarchy
DESCRIPTION
A typical Linux system has, among others, the following directories:
/ This is the root directory. This is where the whole tree
starts.
/bin This directory contains executable programs which are needed in
single user mode and to bring the system up or repair it.
/boot Contains static files for the boot loader. This directory only
holds the files which are needed during the boot process. The
map installer and configuration files should go to /sbin and
/etc.
/dev Special or device files, which refer to physical devices. See
mknod(1).
/dos If both MS-DOS and Linux are run on one computer, this is a
typical place to mount a DOS file system.
/etc Contains configuration files which are local to the machine.
Some larger software packages, like X11, can have their own
subdirectories below /etc. Site-wide configuration files may
be placed here or in /usr/etc. Nevertheless, programs should
always look for these files in /etc and you may have links for
these files to /usr/etc.
/etc/opt
Host-specific configuration files for add-on applications
installed in /opt.
/etc/sgml
This directory contains the configuration files for SGML and
XML (optional).
/etc/skel
When a new user account is created, files from this directory
are usually copied into the user’s home directory.
/etc/X11
Configuration files for the X11 window system (optional).
/home On machines with home directories for users, these are usually
beneath this directory, directly or not. The structure of this
directory depends on local administration decisions.
/lib This directory should hold those shared libraries that are nec-
essary to boot the system and to run the commands in the root
filesystem.
/mnt This directory contains mount points for temporarily mounted
filesystems
/opt This directory should contain add-on packages that contain
static files.
/proc This is a mount point for the proc filesystem, which provides
information about running processes and the kernel. This
pseudo-file system is described in more detail in proc(5).
/root This directory is usually the home directory for the root user
(optional).
/sbin Like /bin, this directory holds commands needed to boot the
system, but which are usually not executed by normal users.
/tmp This directory contains temporary files which may be deleted
with no notice, such as by a regular job or at system boot up.
/usr This directory is usually mounted from a separate partition.
It should hold only sharable, read-only data, so that it can be
mounted by various machines running Linux.
/usr/X11R6
The X-Window system, version 11 release 6 (optional).
/usr/X11R6/bin
Binaries which belong to the X-Windows system; often, there is
a symbolic link from the more traditional /usr/bin/X11 to here.
/usr/X11R6/lib
Data files associated with the X-Windows system.
/usr/X11R6/lib/X11
These contain miscellaneous files needed to run X; Often,
there is a symbolic link from /usr/lib/X11 to this directory.
/usr/X11R6/include/X11
Contains include files needed for compiling programs using the
X11 window system. Often, there is a symbolic link from
/usr/include/X11 to this directory.
/usr/bin
This is the primary directory for executable programs. Most
programs executed by normal users which are not needed for
booting or for repairing the system and which are not installed
locally should be placed in this directory.
/usr/bin/X11
is the traditional place to look for X11 executables; on Linux,
it usually is a symbolic link to /usr/X11R6/bin.
/usr/dict
Replaced by /usr/share/dict.
/usr/doc
Replaced by /usr/share/doc.
/usr/etc
Site-wide configuration files to be shared between several
machines may be stored in this directory. However, commands
should always reference those files using the /etc directory.
Links from files in /etc should point to the appropriate files
in /usr/etc.
/usr/games
Binaries for games and educational programs (optional).
/usr/include
Include files for the C compiler.
/usr/include/X11
Include files for the C compiler and the X-Windows system.
This is usually a symbolic link to /usr/X11R6/include/X11.
/usr/include/asm
Include files which declare some assembler functions. This
used to be a symbolic link to /usr/src/linux/include/asm.
/usr/include/linux
This contains information which may change from system release
to system release and used to be a symbolic link to
/usr/src/linux/include/linux to get at operating system spe-
cific information.
(Note that one should have include files there that work cor-
rectly with the current libc and in user space. However, Linux
kernel source is not designed to be used with user programs and
does not know anything about the libc you are using. It is very
likely that things will break if you let /usr/include/asm and
/usr/include/linux point at a random kernel tree. Debian sys-
tems don’t do this and use headers from a known good kernel
version, provided in the libc*-dev package.)
/usr/include/g++
Include files to use with the GNU C++ compiler.
/usr/lib
Object libraries, including dynamic libraries, plus some exe-
cutables which usually are not invoked directly. More compli-
cated programs may have whole subdirectories there.
/usr/lib/X11
The usual place for data files associated with X programs, and
configuration files for the X system itself. On Linux, it usu-
ally is a symbolic link to /usr/X11R6/lib/X11.
/usr/lib/gcc-lib
contains executables and include files for the GNU C compiler,
gcc(1).
/usr/lib/groff
Files for the GNU groff document formatting system.
/usr/lib/uucp
Files for uucp(1).
/usr/local
This is where programs which are local to the site typically
go.
/usr/local/bin
Binaries for programs local to the site.
/usr/local/doc
Local documentation.
/usr/local/etc
Configuration files associated with locally installed programs.
/usr/local/games
Binaries for locally installed games.
/usr/local/lib
Files associated with locally installed programs.
/usr/local/include
Header files for the local C compiler.
/usr/local/info
Info pages associated with locally installed programs.
/usr/local/man
Man pages associated with locally installed programs.
/usr/local/sbin
Locally installed programs for system administration.
/usr/local/share
Local application data that can be shared among different
architectures of the same OS.
/usr/local/src
Source code for locally installed software.
/usr/man
Replaced by /usr/share/man.
/usr/sbin
This directory contains program binaries for system administra-
tion which are not essential for the boot process, for mounting
/usr, or for system repair.
/usr/share
This directory contains subdirectories with specific applica-
tion data, that can be shared among different architectures of
the same OS. Often one finds stuff here that used to live in
/usr/doc or /usr/lib or /usr/man.
/usr/share/dict
Contains the word lists used by spell checkers.
/usr/share/doc
Documentation about installed programs.
/usr/share/games
Static data files for games in /usr/games.
/usr/share/info
Info pages go here.
/usr/share/locale
Locale information goes here.
/usr/share/man
Manpages go here in subdirectories according to the man page
sections.
/usr/share/man/<locale>/man[1-9]
These directories contain manual pages for the specific locale
in source code form. Systems which use a unique language and
code set for all manual pages may omit the <locale> substring.
/usr/share/misc
Miscellaneous data that can be shared among different architec-
tures of the same OS.
/usr/share/nls
The message catalogs for native language support go here.
/usr/share/sgml
Files for SGML and XML.
/usr/share/terminfo
The datebase for terminfo.
/usr/share/tmac
Troff macros that are not distributed with groff.
/usr/share/zoneinfo
Files for timezone information.
/usr/src
Source files for different parts of the system, included with
some packages for reference purposes. Don’t work here with your
own projects, as files below /usr should be read-only except
when installing software.
/usr/src/linux
This was the traditional place for the kernel source. Some
distributions put here the source for the default kernel they
ship. You should probably use another directory when building
your own kernel.
/usr/tmp
Obsolete. This should be a link to /var/tmp. This link is
present only for compatibility reasons and shouldn’t be used.
/var This directory contains files which may change in size, such as
spool and log files.
/var/adm
This directory is superseded by /var/log and should be a sym-
bolic link to /var/log.
/var/backups
Reserved for historical reasons.
/var/cache
Data cached for programs.
/var/catman/cat[1-9] or /var/cache/man/cat[1-9]
These directories contain preformatted manual pages according
to their man page section. (The use of preformatted manual
pages is deprecated.)
/var/cron
Reserved for historical reasons.
/var/lib
Variable state information for programs.
/var/local
Variable data for /usr/local.
/var/lock
Lock files are placed in this directory. The naming convention
for device lock files is LCK..<device> where <device> is the
device’s name in the filesystem. The format used is that of
HDU UUCP lock files, i.e. lock files contain a PID as a 10-byte
ASCII decimal number, followed by a newline character.
/var/log
Miscellaneous log files.
/var/opt
Variable data for /opt.
/var/mail
Users’ mailboxes. Replaces /var/spool/mail.
/var/msgs
Reserved for historical reasons.
/var/preserve
Reserved for historical reasons.
/var/run
Run-time variable files, like files holding process identifiers
(PIDs) and logged user information (utmp). Files in this
directory are usually cleared when the system boots.
/var/spool
Spooled (or queued) files for various programs.
/var/spool/at
Spooled jobs for at(1).
/var/spool/cron
Spooled jobs for cron(1).
/var/spool/lpd
Spooled files for printing.
/var/spool/mail
Replaced by /var/mail.
/var/spool/mqueue
Queued outgoing mail.
/var/spool/news
Spool directory for news.
/var/spool/rwho
Spooled files for rwhod(8).
/var/spool/smail
Spooled files for the smail(1) mail delivery program.
/var/spool/uucp
Spooled files for uucp(1).
/var/tmp
Like /tmp, this directory holds temporary files stored for an
unspecified duration.
/var/yp
Database files for NIS.
CONFORMS TO
The Filesystem Hierarchy Standard, Version 2.2 <http://www.path-
name.com/fhs/>
BUGS
This list is not exhaustive; different systems may be configured dif-
ferently.
SEE ALSO
find(1), ln(1), mount(1), proc(5), The Filesystem Hierarchy Standard
Linux 2001-09-07 HIER(7)
