pcresample(3)

PCRESAMPLE(3)          C LIBRARY FUNCTIONS          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 ori-
     ginal PCRE 8-bit library, compiles  the  regular  expression
     that  is its first argument, and matches it against the sub-
     ject 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 direc-
     tories for your operating system, you should be able to com-
     pile the demonstration program using this command:

       gcc -o pcredemo pcredemo.c -lpcre

     If PCRE is installed elsewhere, you may need  to  add  addi-
     tional  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_malloc() 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

PCRE 8.30         Last change: 10 January 2012                  1

PCRESAMPLE(3)          C LIBRARY FUNCTIONS          PCRESAMPLE(3)

     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 systems. You need to add

       -R/usr/local/lib

     (for example) to the compile command to get round this prob-
     lem.

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         Last change: 10 January 2012                  2