1<html> 2<head> 3<title>pcresample specification</title> 4</head> 5<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB"> 6<h1>pcresample man page</h1> 7<p> 8Return to the <a href="index.html">PCRE index page</a>. 9</p> 10<p> 11This page is part of the PCRE HTML documentation. It was generated automatically 12from the original man page. If there is any nonsense in it, please consult the 13man page, in case the conversion went wrong. 14<br> 15<br><b> 16PCRE SAMPLE PROGRAM 17</b><br> 18<P> 19A simple, complete demonstration program, to get you started with using PCRE, 20is supplied in the file <i>pcredemo.c</i> in the PCRE distribution. A listing of 21this program is given in the 22<a href="pcredemo.html"><b>pcredemo</b></a> 23documentation. If you do not have a copy of the PCRE distribution, you can save 24this listing to re-create <i>pcredemo.c</i>. 25</P> 26<P> 27The demonstration program, which uses the original PCRE 8-bit library, compiles 28the regular expression that is its first argument, and matches it against the 29subject string in its second argument. No PCRE options are set, and default 30character tables are used. If matching succeeds, the program outputs the 31portion of the subject that matched, together with the contents of any captured 32substrings. 33</P> 34<P> 35If the -g option is given on the command line, the program then goes on to 36check for further matches of the same regular expression in the same subject 37string. The logic is a little bit tricky because of the possibility of matching 38an empty string. Comments in the code explain what is going on. 39</P> 40<P> 41If PCRE is installed in the standard include and library directories for your 42operating system, you should be able to compile the demonstration program using 43this command: 44<pre> 45 gcc -o pcredemo pcredemo.c -lpcre 46</pre> 47If PCRE is installed elsewhere, you may need to add additional options to the 48command line. For example, on a Unix-like system that has PCRE installed in 49<i>/usr/local</i>, you can compile the demonstration program using a command 50like this: 51<pre> 52 gcc -o pcredemo -I/usr/local/include pcredemo.c -L/usr/local/lib -lpcre 53</pre> 54In a Windows environment, if you want to statically link the program against a 55non-dll <b>pcre.a</b> file, you must uncomment the line that defines PCRE_STATIC 56before including <b>pcre.h</b>, because otherwise the <b>pcre_malloc()</b> and 57<b>pcre_free()</b> exported functions will be declared 58<b>__declspec(dllimport)</b>, with unwanted results. 59</P> 60<P> 61Once you have compiled and linked the demonstration program, you can run simple 62tests like this: 63<pre> 64 ./pcredemo 'cat|dog' 'the cat sat on the mat' 65 ./pcredemo -g 'cat|dog' 'the dog sat on the cat' 66</pre> 67Note that there is a much more comprehensive test program, called 68<a href="pcretest.html"><b>pcretest</b>,</a> 69which supports many more facilities for testing regular expressions and both 70PCRE libraries. The 71<a href="pcredemo.html"><b>pcredemo</b></a> 72program is provided as a simple coding example. 73</P> 74<P> 75If you try to run 76<a href="pcredemo.html"><b>pcredemo</b></a> 77when PCRE is not installed in the standard library directory, you may get an 78error like this on some operating systems (e.g. Solaris): 79<pre> 80 ld.so.1: a.out: fatal: libpcre.so.0: open failed: No such file or directory 81</pre> 82This is caused by the way shared library support works on those systems. You 83need to add 84<pre> 85 -R/usr/local/lib 86</pre> 87(for example) to the compile command to get round this problem. 88</P> 89<br><b> 90AUTHOR 91</b><br> 92<P> 93Philip Hazel 94<br> 95University Computing Service 96<br> 97Cambridge CB2 3QH, England. 98<br> 99</P> 100<br><b> 101REVISION 102</b><br> 103<P> 104Last updated: 10 January 2012 105<br> 106Copyright © 1997-2012 University of Cambridge. 107<br> 108<p> 109Return to the <a href="index.html">PCRE index page</a>. 110</p> 111