PCRESAMPLE(3)						     Library Functions Manual						     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 distribution.

       The  program  compiles the regular expression that is its first argument, and matches it against the subject string in its second argument.
       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.

       If  PCRE is installed in the standard include and library directories for your system, you should be able to compile the demonstration pro-
       gram 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 expres-
       sions 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 systems. 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: 23 January 2008
       Copyright (c) 1997-2008 University of Cambridge.

																     PCRESAMPLE(3)