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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.  A
       listing  of this program is given in the pcredemo documentation. If you
       do not have a copy of the PCRE distribution, you can save this  listing
       to re-create pcredemo.c.
       The  demonstration program, which uses the original PCRE 8-bit library,
       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  possi-
       bility  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 operating system, you should be able to compile the demonstra-
       tion 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
       In  a  Windows  environment, if you want to statically link the program
       against a non-dll pcre.a file, you must uncomment the line that defines
       PCRE_STATIC  before  including  pcre.h, because otherwise the pcre_mal-
       loc()   and   pcre_free()   exported   functions   will   be   declared
       __declspec(dllimport), with unwanted results.
       Once  you  have  compiled and linked 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 both PCRE libraries. The pcredemo program  is  provided
       as a simple coding example.
       If  you  try to run pcredemo when PCRE is not installed in the standard
       library directory, you may get an error like  this  on  some  operating
       systems (e.g. Solaris):
         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: 10 January 2012
       Copyright (c) 1997-2012 University of Cambridge.

PCRE 8.30                       10 January 2012                  PCRESAMPLE(3)