xref: /aosp_15_r20/external/pcre/doc/html/pcre2_match.html (revision 22dc650d8ae982c6770746019a6f94af92b0f024)
1<html>
2<head>
3<title>pcre2_match specification</title>
4</head>
5<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
6<h1>pcre2_match man page</h1>
7<p>
8Return to the <a href="index.html">PCRE2 index page</a>.
9</p>
10<p>
11This page is part of the PCRE2 HTML documentation. It was generated
12automatically from the original man page. If there is any nonsense in it,
13please consult the man page, in case the conversion went wrong.
14<br>
15<br><b>
16SYNOPSIS
17</b><br>
18<P>
19<b>#include &#60;pcre2.h&#62;</b>
20</P>
21<P>
22<b>int pcre2_match(const pcre2_code *<i>code</i>, PCRE2_SPTR <i>subject</i>,</b>
23<b>  PCRE2_SIZE <i>length</i>, PCRE2_SIZE <i>startoffset</i>,</b>
24<b>  uint32_t <i>options</i>, pcre2_match_data *<i>match_data</i>,</b>
25<b>  pcre2_match_context *<i>mcontext</i>);</b>
26</P>
27<br><b>
28DESCRIPTION
29</b><br>
30<P>
31This function matches a compiled regular expression against a given subject
32string, using a matching algorithm that is similar to Perl's. It returns
33offsets to what it has matched and to captured substrings via the
34<b>match_data</b> block, which can be processed by functions with names that
35start with <b>pcre2_get_ovector_...()</b> or <b>pcre2_substring_...()</b>. The
36return from <b>pcre2_match()</b> is one more than the highest numbered capturing
37pair that has been set (for example, 1 if there are no captures), zero if the
38vector of offsets is too small, or a negative error code for no match and other
39errors. The function arguments are:
40<pre>
41  <i>code</i>         Points to the compiled pattern
42  <i>subject</i>      Points to the subject string
43  <i>length</i>       Length of the subject string
44  <i>startoffset</i>  Offset in the subject at which to start matching
45  <i>options</i>      Option bits
46  <i>match_data</i>   Points to a match data block, for results
47  <i>mcontext</i>     Points to a match context, or is NULL
48</pre>
49A match context is needed only if you want to:
50<pre>
51  Set up a callout function
52  Set a matching offset limit
53  Change the heap memory limit
54  Change the backtracking match limit
55  Change the backtracking depth limit
56  Set custom memory management specifically for the match
57</pre>
58The <i>length</i> and <i>startoffset</i> values are code units, not characters.
59The length may be given as PCRE2_ZERO_TERMINATED for a subject that is
60terminated by a binary zero code unit. The options are:
61<pre>
62  PCRE2_ANCHORED          Match only at the first position
63  PCRE2_COPY_MATCHED_SUBJECT
64                          On success, make a private subject copy
65  PCRE2_DISABLE_RECURSELOOP_CHECK
66                          Only useful in rare cases; use with care
67  PCRE2_ENDANCHORED       Pattern can match only at end of subject
68  PCRE2_NOTBOL            Subject string is not the beginning of a line
69  PCRE2_NOTEOL            Subject string is not the end of a line
70  PCRE2_NOTEMPTY          An empty string is not a valid match
71  PCRE2_NOTEMPTY_ATSTART  An empty string at the start of the subject is not a valid match
72  PCRE2_NO_JIT            Do not use JIT matching
73  PCRE2_NO_UTF_CHECK      Do not check the subject for UTF validity (only relevant if PCRE2_UTF
74                           was set at compile time)
75  PCRE2_PARTIAL_HARD      Return PCRE2_ERROR_PARTIAL for a partial match even if there is a full match
76  PCRE2_PARTIAL_SOFT      Return PCRE2_ERROR_PARTIAL for a partial match if no full matches are found
77</pre>
78For details of partial matching, see the
79<a href="pcre2partial.html"><b>pcre2partial</b></a>
80page. There is a complete description of the PCRE2 native API in the
81<a href="pcre2api.html"><b>pcre2api</b></a>
82page and a description of the POSIX API in the
83<a href="pcre2posix.html"><b>pcre2posix</b></a>
84page.
85<p>
86Return to the <a href="index.html">PCRE2 index page</a>.
87</p>
88