pcresample

PCRESAMPLE(3)							PCRESAMPLE(3)



NAME
       PCRE - Perl-compatible regular expressions

PCRE SAMPLE PROGRAM

       A  simple,  complete  demonstration  program,  to get you started with
       using PCRE, is supplied in the file pcredemo.c in the  PCRE  distribu-
       tion.

       The  program  compiles  the regular expression that is its first argu-
       ment, and matches it against the subject string in  its	second	argu-
       ment.  No PCRE options are set, and default character tables are used.
       If matching succeeds, the program outputs the portion of	 the  subject
       that matched, together with the contents of any captured substrings.

       If  the	-g option is given on the command line, the program then goes
       on to check for further matches of the same regular expression in  the
       same  subject  string. The logic is a little bit tricky because of the
       possibility of matching an empty string. Comments in the code  explain
       what is going on.

       The demonstration program is automatically built if you use "./config-
       ure;make" to build PCRE. Otherwise, if PCRE is installed in the	stan-
       dard  include  and  library directories for your system, you should be
       able to compile the demonstration program using this command:

	 gcc -o pcredemo pcredemo.c -lpcre

       If PCRE is installed elsewhere, you may need to add additional options
       to  the command line. For example, on a Unix-like system that has PCRE
       installed in /usr/local, you can	 compile  the  demonstration  program
       using a command like this:

	 gcc -o pcredemo -I/usr/local/include pcredemo.c \
	     -L/usr/local/lib -lpcre

       Once  you  have compiled the demonstration program, you can run simple
       tests like this:

	 ./pcredemo ’cat|dog’ ’the cat sat on the mat’
	 ./pcredemo -g ’cat|dog’ ’the dog sat on the cat’

       Note that there is a much  more	comprehensive  test  program,  called
       pcretest,  which	 supports  many	 more  facilities for testing regular
       expressions and the PCRE library. The pcredemo program is provided  as
       a simple coding example.

       On  some	 operating systems (e.g. Solaris), when PCRE is not installed
       in the standard library directory, you may get an error like this when
       you try to run pcredemo:

	 ld.so.1:  a.out:  fatal:  libpcre.so.0: open failed: No such file or
       directory

       This is caused by the way shared library support works on  those	 sys-
       tems. You need to add

	 -R/usr/local/lib

       (for example) to the compile command to get round this problem.

AUTHOR

       Philip Hazel
       University Computing Service
       Cambridge CB2 3QH, England.

REVISION

       Last updated: 13 June 2007
       Copyright (c) 1997-2007 University of Cambridge.



								PCRESAMPLE(3)