1<html> 2<head> 3<title>pcre2_dfa_match specification</title> 4</head> 5<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB"> 6<h1>pcre2_dfa_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 <pcre2.h></b> 20</P> 21<P> 22<b>int pcre2_dfa_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<b> int *<i>workspace</i>, PCRE2_SIZE <i>wscount</i>);</b> 27</P> 28<br><b> 29DESCRIPTION 30</b><br> 31<P> 32This function matches a compiled regular expression against a given subject 33string, using an alternative matching algorithm that scans the subject string 34just once (except when processing lookaround assertions). This function is 35<i>not</i> Perl-compatible (the Perl-compatible matching function is 36<b>pcre2_match()</b>). The arguments for this function are: 37<pre> 38 <i>code</i> Points to the compiled pattern 39 <i>subject</i> Points to the subject string 40 <i>length</i> Length of the subject string 41 <i>startoffset</i> Offset in the subject at which to start matching 42 <i>options</i> Option bits 43 <i>match_data</i> Points to a match data block, for results 44 <i>mcontext</i> Points to a match context, or is NULL 45 <i>workspace</i> Points to a vector of ints used as working space 46 <i>wscount</i> Number of elements in the vector 47</pre> 48The size of output vector needed to contain all the results depends on the 49number of simultaneous matches, not on the number of parentheses in the 50pattern. Using <b>pcre2_match_data_create_from_pattern()</b> to create the match 51data block is therefore not advisable when using this function. 52</P> 53<P> 54A match context is needed only if you want to set up a callout function or 55specify the heap limit or the match or the recursion depth limits. The 56<i>length</i> and <i>startoffset</i> values are code units, not characters. The 57options are: 58<pre> 59 PCRE2_ANCHORED Match only at the first position 60 PCRE2_COPY_MATCHED_SUBJECT 61 On success, make a private subject copy 62 PCRE2_ENDANCHORED Pattern can match only at end of subject 63 PCRE2_NOTBOL Subject is not the beginning of a line 64 PCRE2_NOTEOL Subject is not the end of a line 65 PCRE2_NOTEMPTY An empty string is not a valid match 66 PCRE2_NOTEMPTY_ATSTART An empty string at the start of the subject is not a valid match 67 PCRE2_NO_UTF_CHECK Do not check the subject for UTF validity (only relevant if PCRE2_UTF 68 was set at compile time) 69 PCRE2_PARTIAL_HARD Return PCRE2_ERROR_PARTIAL for a partial match even if there is a full match 70 PCRE2_PARTIAL_SOFT Return PCRE2_ERROR_PARTIAL for a partial match if no full matches are found 71 PCRE2_DFA_RESTART Restart after a partial match 72 PCRE2_DFA_SHORTEST Return only the shortest match 73</pre> 74There are restrictions on what may appear in a pattern when using this matching 75function. Details are given in the 76<a href="pcre2matching.html"><b>pcre2matching</b></a> 77documentation. For details of partial matching, see the 78<a href="pcre2partial.html"><b>pcre2partial</b></a> 79page. There is a complete description of the PCRE2 native API in the 80<a href="pcre2api.html"><b>pcre2api</b></a> 81page and a description of the POSIX API in the 82<a href="pcre2posix.html"><b>pcre2posix</b></a> 83page. 84<p> 85Return to the <a href="index.html">PCRE2 index page</a>. 86</p> 87