pcre/doc/html/pcre_dfa_exec.html

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<title>pcre_dfa_exec specification</title>
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<h1>pcre_dfa_exec man page</h1>
<p>
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</p>
<p>
This page is part of the PCRE HTML documentation. It was generated automatically
from the original man page. If there is any nonsense in it, please consult the
man page, in case the conversion went wrong.
<br>
<br><b>
SYNOPSIS
</b><br>
<P>
<b>#include &#60;pcre.h&#62;</b>
</P>
<P>
<b>int pcre_dfa_exec(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
<b> const char *<i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
<b> int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
<b> int *<i>workspace</i>, int <i>wscount</i>);</b>
<br>
<br>
<b>int pcre16_dfa_exec(const pcre16 *<i>code</i>, const pcre16_extra *<i>extra</i>,</b>
<b> PCRE_SPTR16 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
<b> int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
<b> int *<i>workspace</i>, int <i>wscount</i>);</b>
<br>
<br>
<b>int pcre32_dfa_exec(const pcre32 *<i>code</i>, const pcre32_extra *<i>extra</i>,</b>
<b> PCRE_SPTR32 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
<b> int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
<b> int *<i>workspace</i>, int <i>wscount</i>);</b>
</P>
<br><b>
DESCRIPTION
</b><br>
<P>
This function matches a compiled regular expression against a given subject
string, using an alternative matching algorithm that scans the subject string
just once (<i>not</i> Perl-compatible). Note that the main, Perl-compatible,
matching function is <b>pcre[16|32]_exec()</b>. The arguments for this function
are:
<pre>
<i>code</i> Points to the compiled pattern
<i>extra</i> Points to an associated <b>pcre[16|32]_extra</b> structure,
or is NULL
<i>subject</i> Points to the subject string
<i>length</i> Length of the subject string
<i>startoffset</i> Offset in the subject at which to start matching
<i>options</i> Option bits
<i>ovector</i> Points to a vector of ints for result offsets
<i>ovecsize</i> Number of elements in the vector
<i>workspace</i> Points to a vector of ints used as working space
<i>wscount</i> Number of elements in the vector
</pre>
The units for <i>length</i> and <i>startoffset</i> are bytes for
<b>pcre_exec()</b>, 16-bit data items for <b>pcre16_exec()</b>, and 32-bit items
for <b>pcre32_exec()</b>. The options are:
<pre>
PCRE_ANCHORED Match only at the first position
PCRE_BSR_ANYCRLF \R matches only CR, LF, or CRLF
PCRE_BSR_UNICODE \R matches all Unicode line endings
PCRE_NEWLINE_ANY Recognize any Unicode newline sequence
PCRE_NEWLINE_ANYCRLF Recognize CR, LF, & CRLF as newline sequences
PCRE_NEWLINE_CR Recognize CR as the only newline sequence
PCRE_NEWLINE_CRLF Recognize CRLF as the only newline sequence
PCRE_NEWLINE_LF Recognize LF as the only newline sequence
PCRE_NOTBOL Subject is not the beginning of a line
PCRE_NOTEOL Subject is not the end of a line
PCRE_NOTEMPTY An empty string is not a valid match
PCRE_NOTEMPTY_ATSTART An empty string at the start of the subject
is not a valid match
PCRE_NO_START_OPTIMIZE Do not do "start-match" optimizations
PCRE_NO_UTF16_CHECK Do not check the subject for UTF-16
validity (only relevant if PCRE_UTF16
was set at compile time)
PCRE_NO_UTF32_CHECK Do not check the subject for UTF-32
validity (only relevant if PCRE_UTF32
was set at compile time)
PCRE_NO_UTF8_CHECK Do not check the subject for UTF-8
validity (only relevant if PCRE_UTF8
was set at compile time)
PCRE_PARTIAL ) Return PCRE_ERROR_PARTIAL for a partial
PCRE_PARTIAL_SOFT ) match if no full matches are found
PCRE_PARTIAL_HARD Return PCRE_ERROR_PARTIAL for a partial match
even if there is a full match as well
PCRE_DFA_SHORTEST Return only the shortest match
PCRE_DFA_RESTART Restart after a partial match
</pre>
There are restrictions on what may appear in a pattern when using this matching
function. Details are given in the
<a href="pcrematching.html"><b>pcrematching</b></a>
documentation. For details of partial matching, see the
<a href="pcrepartial.html"><b>pcrepartial</b></a>
page.
</P>
<P>
A <b>pcre[16|32]_extra</b> structure contains the following fields:
<pre>
<i>flags</i> Bits indicating which fields are set
<i>study_data</i> Opaque data from <b>pcre[16|32]_study()</b>
<i>match_limit</i> Limit on internal resource use
<i>match_limit_recursion</i> Limit on internal recursion depth
<i>callout_data</i> Opaque data passed back to callouts
<i>tables</i> Points to character tables or is NULL
<i>mark</i> For passing back a *MARK pointer
<i>executable_jit</i> Opaque data from JIT compilation
</pre>
The flag bits are PCRE_EXTRA_STUDY_DATA, PCRE_EXTRA_MATCH_LIMIT,
PCRE_EXTRA_MATCH_LIMIT_RECURSION, PCRE_EXTRA_CALLOUT_DATA,
PCRE_EXTRA_TABLES, PCRE_EXTRA_MARK and PCRE_EXTRA_EXECUTABLE_JIT. For this
matching function, the <i>match_limit</i> and <i>match_limit_recursion</i> fields
are not used, and must not be set. The PCRE_EXTRA_EXECUTABLE_JIT flag and
the corresponding variable are ignored.
</P>
<P>
There is a complete description of the PCRE native API in the
<a href="pcreapi.html"><b>pcreapi</b></a>
page and a description of the POSIX API in the
<a href="pcreposix.html"><b>pcreposix</b></a>
page.
<p>
Return to the <a href="index.html">PCRE index page</a>.
</p>