1<html>
2<head>
3<title>pcre_exec specification</title>
4</head>
5<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
6<h1>pcre_exec 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>
16SYNOPSIS
17</b><br>
18<P>
19<b>#include &#60;pcre.h&#62;</b>
20</P>
21<P>
22<b>int pcre_exec(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
23<b>const char *<i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
24<b>int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>);</b>
25</P>
26<br><b>
27DESCRIPTION
28</b><br>
29<P>
30This function matches a compiled regular expression against a given subject
31string, using a matching algorithm that is similar to Perl's. It returns
32offsets to captured substrings. Its arguments are:
33<pre>
34  <i>code</i>         Points to the compiled pattern
35  <i>extra</i>        Points to an associated <b>pcre_extra</b> structure,
36                 or is NULL
37  <i>subject</i>      Points to the subject string
38  <i>length</i>       Length of the subject string, in bytes
39  <i>startoffset</i>  Offset in bytes in the subject at which to
40                 start matching
41  <i>options</i>      Option bits
42  <i>ovector</i>      Points to a vector of ints for result offsets
43  <i>ovecsize</i>     Number of elements in the vector (a multiple of 3)
44</pre>
45The options are:
46<pre>
47  PCRE_ANCHORED          Match only at the first position
48  PCRE_BSR_ANYCRLF       \R matches only CR, LF, or CRLF
49  PCRE_BSR_UNICODE       \R matches all Unicode line endings
50  PCRE_NEWLINE_ANY       Recognize any Unicode newline sequence
51  PCRE_NEWLINE_ANYCRLF   Recognize CR, LF, & CRLF as newline sequences
52  PCRE_NEWLINE_CR        Recognize CR as the only newline sequence
53  PCRE_NEWLINE_CRLF      Recognize CRLF as the only newline sequence
54  PCRE_NEWLINE_LF        Recognize LF as the only newline sequence
55  PCRE_NOTBOL            Subject string is not the beginning of a line
56  PCRE_NOTEOL            Subject string is not the end of a line
57  PCRE_NOTEMPTY          An empty string is not a valid match
58  PCRE_NOTEMPTY_ATSTART  An empty string at the start of the subject
59                           is not a valid match
60  PCRE_NO_START_OPTIMIZE Do not do "start-match" optimizations
61  PCRE_NO_UTF8_CHECK     Do not check the subject for UTF-8
62                           validity (only relevant if PCRE_UTF8
63                           was set at compile time)
64  PCRE_PARTIAL           ) Return PCRE_ERROR_PARTIAL for a partial
65  PCRE_PARTIAL_SOFT      )   match if no full matches are found
66  PCRE_PARTIAL_HARD      Return PCRE_ERROR_PARTIAL for a partial match
67                           even if there is a full match as well
68</pre>
69For details of partial matching, see the
70<a href="pcrepartial.html"><b>pcrepartial</b></a>
71page. A <b>pcre_extra</b> structure contains the following fields:
72<pre>
73  <i>flags</i>        Bits indicating which fields are set
74  <i>study_data</i>   Opaque data from <b>pcre_study()</b>
75  <i>match_limit</i>  Limit on internal resource use
76  <i>match_limit_recursion</i>  Limit on internal recursion depth
77  <i>callout_data</i> Opaque data passed back to callouts
78  <i>tables</i>       Points to character tables or is NULL
79</pre>
80The flag bits are PCRE_EXTRA_STUDY_DATA, PCRE_EXTRA_MATCH_LIMIT,
81PCRE_EXTRA_MATCH_LIMIT_RECURSION, PCRE_EXTRA_CALLOUT_DATA, and
82PCRE_EXTRA_TABLES.
83</P>
84<P>
85There is a complete description of the PCRE native API in the
86<a href="pcreapi.html"><b>pcreapi</b></a>
87page and a description of the POSIX API in the
88<a href="pcreposix.html"><b>pcreposix</b></a>
89page.
90<p>
91Return to the <a href="index.html">PCRE index page</a>.
92</p>
93