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Line 14 man page, in case the conversion went wrong.	Line 14 man page, in case the conversion went wrong.
<br>	<br>
<ul>	<ul>
<li><a name="TOC1" href="#SEC1">PCRE NATIVE API BASIC FUNCTIONS</a>	<li><a name="TOC1" href="#SEC1">PCRE NATIVE API BASIC FUNCTIONS</a>
<li><a name="TOC2" href="#SEC2">PCRE NATIVE API AUXILIARY FUNCTIONS</a>	<li><a name="TOC2" href="#SEC2">PCRE NATIVE API STRING EXTRACTION FUNCTIONS</a>
<li><a name="TOC3" href="#SEC3">PCRE NATIVE API INDIRECTED FUNCTIONS</a>	<li><a name="TOC3" href="#SEC3">PCRE NATIVE API AUXILIARY FUNCTIONS</a>
<li><a name="TOC4" href="#SEC4">PCRE API OVERVIEW</a>	<li><a name="TOC4" href="#SEC4">PCRE NATIVE API INDIRECTED FUNCTIONS</a>
<li><a name="TOC5" href="#SEC5">NEWLINES</a>	<li><a name="TOC5" href="#SEC5">PCRE 8-BIT, 16-BIT, AND 32-BIT LIBRARIES</a>
<li><a name="TOC6" href="#SEC6">MULTITHREADING</a>	<li><a name="TOC6" href="#SEC6">PCRE API OVERVIEW</a>
<li><a name="TOC7" href="#SEC7">SAVING PRECOMPILED PATTERNS FOR LATER USE</a>	<li><a name="TOC7" href="#SEC7">NEWLINES</a>
<li><a name="TOC8" href="#SEC8">CHECKING BUILD-TIME OPTIONS</a>	<li><a name="TOC8" href="#SEC8">MULTITHREADING</a>
<li><a name="TOC9" href="#SEC9">COMPILING A PATTERN</a>	<li><a name="TOC9" href="#SEC9">SAVING PRECOMPILED PATTERNS FOR LATER USE</a>
<li><a name="TOC10" href="#SEC10">COMPILATION ERROR CODES</a>	<li><a name="TOC10" href="#SEC10">CHECKING BUILD-TIME OPTIONS</a>
<li><a name="TOC11" href="#SEC11">STUDYING A PATTERN</a>	<li><a name="TOC11" href="#SEC11">COMPILING A PATTERN</a>
<li><a name="TOC12" href="#SEC12">LOCALE SUPPORT</a>	<li><a name="TOC12" href="#SEC12">COMPILATION ERROR CODES</a>
<li><a name="TOC13" href="#SEC13">INFORMATION ABOUT A PATTERN</a>	<li><a name="TOC13" href="#SEC13">STUDYING A PATTERN</a>
<li><a name="TOC14" href="#SEC14">OBSOLETE INFO FUNCTION</a>	<li><a name="TOC14" href="#SEC14">LOCALE SUPPORT</a>
<li><a name="TOC15" href="#SEC15">REFERENCE COUNTS</a>	<li><a name="TOC15" href="#SEC15">INFORMATION ABOUT A PATTERN</a>
<li><a name="TOC16" href="#SEC16">MATCHING A PATTERN: THE TRADITIONAL FUNCTION</a>	<li><a name="TOC16" href="#SEC16">REFERENCE COUNTS</a>
<li><a name="TOC17" href="#SEC17">EXTRACTING CAPTURED SUBSTRINGS BY NUMBER</a>	<li><a name="TOC17" href="#SEC17">MATCHING A PATTERN: THE TRADITIONAL FUNCTION</a>
<li><a name="TOC18" href="#SEC18">EXTRACTING CAPTURED SUBSTRINGS BY NAME</a>	<li><a name="TOC18" href="#SEC18">EXTRACTING CAPTURED SUBSTRINGS BY NUMBER</a>
<li><a name="TOC19" href="#SEC19">DUPLICATE SUBPATTERN NAMES</a>	<li><a name="TOC19" href="#SEC19">EXTRACTING CAPTURED SUBSTRINGS BY NAME</a>
<li><a name="TOC20" href="#SEC20">FINDING ALL POSSIBLE MATCHES</a>	<li><a name="TOC20" href="#SEC20">DUPLICATE SUBPATTERN NAMES</a>
<li><a name="TOC21" href="#SEC21">MATCHING A PATTERN: THE ALTERNATIVE FUNCTION</a>	<li><a name="TOC21" href="#SEC21">FINDING ALL POSSIBLE MATCHES</a>
<li><a name="TOC22" href="#SEC22">SEE ALSO</a>	<li><a name="TOC22" href="#SEC22">OBTAINING AN ESTIMATE OF STACK USAGE</a>
<li><a name="TOC23" href="#SEC23">AUTHOR</a>	<li><a name="TOC23" href="#SEC23">MATCHING A PATTERN: THE ALTERNATIVE FUNCTION</a>
<li><a name="TOC24" href="#SEC24">REVISION</a>	<li><a name="TOC24" href="#SEC24">SEE ALSO</a>
	<li><a name="TOC25" href="#SEC25">AUTHOR</a>
	<li><a name="TOC26" href="#SEC26">REVISION</a>
</ul>	</ul>
<br><a name="SEC1" href="#TOC1">PCRE NATIVE API BASIC FUNCTIONS</a><br>
<P>	<P>
<b>#include <pcre.h></b>	<b>#include <pcre.h></b>
</P>	</P>
	<br><a name="SEC1" href="#TOC1">PCRE NATIVE API BASIC FUNCTIONS</a><br>
<P>	<P>
<b>pcre pcre_compile(const char <i>pattern</i>, int <i>options</i>,</b>	<b>pcre pcre_compile(const char <i>pattern</i>, int <i>options</i>,</b>
<b>const char *<i>errptr</i>, int <i>erroffset</i>,</b>	<b> const char *<i>errptr</i>, int <i>erroffset</i>,</b>
<b>const unsigned char *<i>tableptr</i>);</b>	<b> const unsigned char *<i>tableptr</i>);</b>
</P>	<br>
<P>	<br>
<b>pcre pcre_compile2(const char <i>pattern</i>, int <i>options</i>,</b>	<b>pcre pcre_compile2(const char <i>pattern</i>, int <i>options</i>,</b>
<b>int *<i>errorcodeptr</i>,</b>	<b> int *<i>errorcodeptr</i>,</b>
<b>const char *<i>errptr</i>, int <i>erroffset</i>,</b>	<b> const char *<i>errptr</i>, int <i>erroffset</i>,</b>
<b>const unsigned char *<i>tableptr</i>);</b>	<b> const unsigned char *<i>tableptr</i>);</b>
</P>	<br>
<P>	<br>
<b>pcre_extra pcre_study(const pcre <i>code</i>, int <i>options</i>,</b>	<b>pcre_extra pcre_study(const pcre <i>code</i>, int <i>options</i>,</b>
<b>const char **<i>errptr</i>);</b>	<b> const char **<i>errptr</i>);</b>
</P>	<br>
<P>	<br>
<b>void pcre_free_study(pcre_extra *<i>extra</i>);</b>	<b>void pcre_free_study(pcre_extra *<i>extra</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_exec(const pcre <i>code</i>, const pcre_extra <i>extra</i>,</b>	<b>int pcre_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> 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>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>);</b>
</P>	<br>
<br><a name="SEC2" href="#TOC1">PCRE NATIVE API AUXILIARY FUNCTIONS</a><br>	<br>
<P>
<b>pcre_jit_stack *pcre_jit_stack_alloc(int <i>startsize</i>, int <i>maxsize</i>);</b>
</P>
<P>
<b>void pcre_jit_stack_free(pcre_jit_stack *<i>stack</i>);</b>
</P>
<P>
<b>void pcre_assign_jit_stack(pcre_extra *<i>extra</i>,</b>
<b>pcre_jit_callback <i>callback</i>, void *<i>data</i>);</b>
</P>
<P>
<b>int pcre_dfa_exec(const pcre <i>code</i>, const pcre_extra <i>extra</i>,</b>	<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> 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>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
<b>int *<i>workspace</i>, int <i>wscount</i>);</b>	<b> int *<i>workspace</i>, int <i>wscount</i>);</b>
</P>	</P>
	<br><a name="SEC2" href="#TOC1">PCRE NATIVE API STRING EXTRACTION FUNCTIONS</a><br>
<P>	<P>
<b>int pcre_copy_named_substring(const pcre *<i>code</i>,</b>	<b>int pcre_copy_named_substring(const pcre *<i>code</i>,</b>
<b>const char <i>subject</i>, int <i>ovector</i>,</b>	<b> const char <i>subject</i>, int <i>ovector</i>,</b>
<b>int <i>stringcount</i>, const char *<i>stringname</i>,</b>	<b> int <i>stringcount</i>, const char *<i>stringname</i>,</b>
<b>char *<i>buffer</i>, int <i>buffersize</i>);</b>	<b> char *<i>buffer</i>, int <i>buffersize</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_copy_substring(const char <i>subject</i>, int <i>ovector</i>,</b>	<b>int pcre_copy_substring(const char <i>subject</i>, int <i>ovector</i>,</b>
<b>int <i>stringcount</i>, int <i>stringnumber</i>, char *<i>buffer</i>,</b>	<b> int <i>stringcount</i>, int <i>stringnumber</i>, char *<i>buffer</i>,</b>
<b>int <i>buffersize</i>);</b>	<b> int <i>buffersize</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_get_named_substring(const pcre *<i>code</i>,</b>	<b>int pcre_get_named_substring(const pcre *<i>code</i>,</b>
<b>const char <i>subject</i>, int <i>ovector</i>,</b>	<b> const char <i>subject</i>, int <i>ovector</i>,</b>
<b>int <i>stringcount</i>, const char *<i>stringname</i>,</b>	<b> int <i>stringcount</i>, const char *<i>stringname</i>,</b>
<b>const char **<i>stringptr</i>);</b>	<b> const char **<i>stringptr</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_get_stringnumber(const pcre *<i>code</i>,</b>	<b>int pcre_get_stringnumber(const pcre *<i>code</i>,</b>
<b>const char *<i>name</i>);</b>	<b> const char *<i>name</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_get_stringtable_entries(const pcre *<i>code</i>,</b>	<b>int pcre_get_stringtable_entries(const pcre *<i>code</i>,</b>
<b>const char <i>name</i>, char <i>first</i>, char *<i>last</i>);</b>	<b> const char <i>name</i>, char <i>first</i>, char *<i>last</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_get_substring(const char <i>subject</i>, int <i>ovector</i>,</b>	<b>int pcre_get_substring(const char <i>subject</i>, int <i>ovector</i>,</b>
<b>int <i>stringcount</i>, int <i>stringnumber</i>,</b>	<b> int <i>stringcount</i>, int <i>stringnumber</i>,</b>
<b>const char **<i>stringptr</i>);</b>	<b> const char **<i>stringptr</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_get_substring_list(const char *<i>subject</i>,</b>	<b>int pcre_get_substring_list(const char *<i>subject</i>,</b>
<b>int <i>ovector</i>, int <i>stringcount</i>, const char **<i>listptr</i>);</b>	<b> int <i>ovector</i>, int <i>stringcount</i>, const char **<i>listptr</i>);</b>
</P>	<br>
<P>	<br>
<b>void pcre_free_substring(const char *<i>stringptr</i>);</b>	<b>void pcre_free_substring(const char *<i>stringptr</i>);</b>
</P>	<br>
<P>	<br>
<b>void pcre_free_substring_list(const char **<i>stringptr</i>);</b>	<b>void pcre_free_substring_list(const char **<i>stringptr</i>);</b>
</P>	</P>
	<br><a name="SEC3" href="#TOC1">PCRE NATIVE API AUXILIARY FUNCTIONS</a><br>
<P>	<P>
	<b>int pcre_jit_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> pcre_jit_stack *<i>jstack</i>);</b>
	<br>
	<br>
	<b>pcre_jit_stack *pcre_jit_stack_alloc(int <i>startsize</i>, int <i>maxsize</i>);</b>
	<br>
	<br>
	<b>void pcre_jit_stack_free(pcre_jit_stack *<i>stack</i>);</b>
	<br>
	<br>
	<b>void pcre_assign_jit_stack(pcre_extra *<i>extra</i>,</b>
	<b> pcre_jit_callback <i>callback</i>, void *<i>data</i>);</b>
	<br>
	<br>
<b>const unsigned char *pcre_maketables(void);</b>	<b>const unsigned char *pcre_maketables(void);</b>
</P>	<br>
<P>	<br>
<b>int pcre_fullinfo(const pcre <i>code</i>, const pcre_extra <i>extra</i>,</b>	<b>int pcre_fullinfo(const pcre <i>code</i>, const pcre_extra <i>extra</i>,</b>
<b>int <i>what</i>, void *<i>where</i>);</b>	<b> int <i>what</i>, void *<i>where</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_info(const pcre <i>code</i>, int <i>optptr</i>, int</b>
<b>*<i>firstcharptr</i>);</b>
</P>
<P>
<b>int pcre_refcount(pcre *<i>code</i>, int <i>adjust</i>);</b>	<b>int pcre_refcount(pcre *<i>code</i>, int <i>adjust</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_config(int <i>what</i>, void *<i>where</i>);</b>	<b>int pcre_config(int <i>what</i>, void *<i>where</i>);</b>
	<br>
	<br>
	<b>const char *pcre_version(void);</b>
	<br>
	<br>
	<b>int pcre_pattern_to_host_byte_order(pcre *<i>code</i>,</b>
	<b> pcre_extra <i>extra</i>, const unsigned char <i>tables</i>);</b>
</P>	</P>
	<br><a name="SEC4" href="#TOC1">PCRE NATIVE API INDIRECTED FUNCTIONS</a><br>
<P>	<P>
<b>char *pcre_version(void);</b>
</P>
<br><a name="SEC3" href="#TOC1">PCRE NATIVE API INDIRECTED FUNCTIONS</a><br>
<P>
<b>void (pcre_malloc)(size_t);</b>	<b>void (pcre_malloc)(size_t);</b>
</P>	<br>
<P>	<br>
<b>void (pcre_free)(void );</b>	<b>void (pcre_free)(void );</b>
	<br>
	<br>
	<b>void (pcre_stack_malloc)(size_t);</b>
	<br>
	<br>
	<b>void (pcre_stack_free)(void );</b>
	<br>
	<br>
	<b>int (pcre_callout)(pcre_callout_block );</b>
</P>	</P>
	<br><a name="SEC5" href="#TOC1">PCRE 8-BIT, 16-BIT, AND 32-BIT LIBRARIES</a><br>
<P>	<P>
<b>void (pcre_stack_malloc)(size_t);</b>	As well as support for 8-bit character strings, PCRE also supports 16-bit
	strings (from release 8.30) and 32-bit strings (from release 8.32), by means of
	two additional libraries. They can be built as well as, or instead of, the
	8-bit library. To avoid too much complication, this document describes the
	8-bit versions of the functions, with only occasional references to the 16-bit
	and 32-bit libraries.
</P>	</P>
<P>	<P>
<b>void (pcre_stack_free)(void );</b>	The 16-bit and 32-bit functions operate in the same way as their 8-bit
	counterparts; they just use different data types for their arguments and
	results, and their names start with <b>pcre16_</b> or <b>pcre32_</b> instead of
	<b>pcre_</b>. For every option that has UTF8 in its name (for example,
	PCRE_UTF8), there are corresponding 16-bit and 32-bit names with UTF8 replaced
	by UTF16 or UTF32, respectively. This facility is in fact just cosmetic; the
	16-bit and 32-bit option names define the same bit values.
</P>	</P>
<P>	<P>
<b>int (pcre_callout)(pcre_callout_block );</b>	References to bytes and UTF-8 in this document should be read as references to
	16-bit data units and UTF-16 when using the 16-bit library, or 32-bit data
	units and UTF-32 when using the 32-bit library, unless specified otherwise.
	More details of the specific differences for the 16-bit and 32-bit libraries
	are given in the
	<a href="pcre16.html"><b>pcre16</b></a>
	and
	<a href="pcre32.html"><b>pcre32</b></a>
	pages.
</P>	</P>
<br><a name="SEC4" href="#TOC1">PCRE API OVERVIEW</a><br>	<br><a name="SEC6" href="#TOC1">PCRE API OVERVIEW</a><br>
<P>	<P>
PCRE has its own native API, which is described in this document. There are	PCRE has its own native API, which is described in this document. There are
also some wrapper functions that correspond to the POSIX regular expression	also some wrapper functions (for the 8-bit library only) that correspond to the
API, but they do not give access to all the functionality. They are described	POSIX regular expression API, but they do not give access to all the
in the	functionality. They are described in the
<a href="pcreposix.html"><b>pcreposix</b></a>	<a href="pcreposix.html"><b>pcreposix</b></a>
documentation. Both of these APIs define a set of C function calls. A C++	documentation. Both of these APIs define a set of C function calls. A C++
wrapper is also distributed with PCRE. It is documented in the	wrapper (again for the 8-bit library only) is also distributed with PCRE. It is
	documented in the
<a href="pcrecpp.html"><b>pcrecpp</b></a>	<a href="pcrecpp.html"><b>pcrecpp</b></a>
page.	page.
</P>	</P>
<P>	<P>
The native API C function prototypes are defined in the header file	The native API C function prototypes are defined in the header file
<b>pcre.h</b>, and on Unix systems the library itself is called <b>libpcre</b>.	<b>pcre.h</b>, and on Unix-like systems the (8-bit) library itself is called
It can normally be accessed by adding <b>-lpcre</b> to the command for linking	<b>libpcre</b>. It can normally be accessed by adding <b>-lpcre</b> to the
an application that uses PCRE. The header file defines the macros PCRE_MAJOR	command for linking an application that uses PCRE. The header file defines the
and PCRE_MINOR to contain the major and minor release numbers for the library.	macros PCRE_MAJOR and PCRE_MINOR to contain the major and minor release numbers
Applications can use these to include support for different releases of PCRE.	for the library. Applications can use these to include support for different
	releases of PCRE.
</P>	</P>
<P>	<P>
In a Windows environment, if you want to statically link an application program	In a Windows environment, if you want to statically link an application program
Line 204 used if available, by setting an option that is ignore	Line 244 used if available, by setting an option that is ignore
relevant. More complicated programs might need to make use of the functions	relevant. More complicated programs might need to make use of the functions
<b>pcre_jit_stack_alloc()</b>, <b>pcre_jit_stack_free()</b>, and	<b>pcre_jit_stack_alloc()</b>, <b>pcre_jit_stack_free()</b>, and
<b>pcre_assign_jit_stack()</b> in order to control the JIT code's memory usage.	<b>pcre_assign_jit_stack()</b> in order to control the JIT code's memory usage.
These functions are discussed in the	</P>
	<P>
	From release 8.32 there is also a direct interface for JIT execution, which
	gives improved performance. The JIT-specific functions are discussed in the
<a href="pcrejit.html"><b>pcrejit</b></a>	<a href="pcrejit.html"><b>pcrejit</b></a>
documentation.	documentation.
</P>	</P>
Line 244 internal tables that are generated when PCRE is built	Line 287 internal tables that are generated when PCRE is built
</P>	</P>
<P>	<P>
The function <b>pcre_fullinfo()</b> is used to find out information about a	The function <b>pcre_fullinfo()</b> is used to find out information about a
compiled pattern; <b>pcre_info()</b> is an obsolete version that returns only	compiled pattern. The function <b>pcre_version()</b> returns a pointer to a
some of the available information, but is retained for backwards compatibility.	string containing the version of PCRE and its date of release.
The function <b>pcre_version()</b> returns a pointer to a string containing the
version of PCRE and its date of release.
</P>	</P>
<P>	<P>
The function <b>pcre_refcount()</b> maintains a reference count in a data block	The function <b>pcre_refcount()</b> maintains a reference count in a data block
Line 284 points during a matching operation. Details are given	Line 325 points during a matching operation. Details are given
<a href="pcrecallout.html"><b>pcrecallout</b></a>	<a href="pcrecallout.html"><b>pcrecallout</b></a>
documentation.	documentation.
<a name="newlines"></a></P>	<a name="newlines"></a></P>
<br><a name="SEC5" href="#TOC1">NEWLINES</a><br>	<br><a name="SEC7" href="#TOC1">NEWLINES</a><br>
<P>	<P>
PCRE supports five different conventions for indicating line breaks in	PCRE supports five different conventions for indicating line breaks in
strings: a single CR (carriage return) character, a single LF (linefeed)	strings: a single CR (carriage return) character, a single LF (linefeed)
character, the two-character sequence CRLF, any of the three preceding, or any	character, the two-character sequence CRLF, any of the three preceding, or any
Unicode newline sequence. The Unicode newline sequences are the three just	Unicode newline sequence. The Unicode newline sequences are the three just
mentioned, plus the single characters VT (vertical tab, U+000B), FF (formfeed,	mentioned, plus the single characters VT (vertical tab, U+000B), FF (form feed,
U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS	U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS
(paragraph separator, U+2029).	(paragraph separator, U+2029).
</P>	</P>
Line 323 The choice of newline convention does not affect the i	Line 364 The choice of newline convention does not affect the i
the \n or \r escape sequences, nor does it affect what \R matches, which is	the \n or \r escape sequences, nor does it affect what \R matches, which is
controlled in a similar way, but by separate options.	controlled in a similar way, but by separate options.
</P>	</P>
<br><a name="SEC6" href="#TOC1">MULTITHREADING</a><br>	<br><a name="SEC8" href="#TOC1">MULTITHREADING</a><br>
<P>	<P>
The PCRE functions can be used in multi-threading applications, with the	The PCRE functions can be used in multi-threading applications, with the
proviso that the memory management functions pointed to by <b>pcre_malloc</b>,	proviso that the memory management functions pointed to by <b>pcre_malloc</b>,
Line 340 memory stack areas for each thread. See the	Line 381 memory stack areas for each thread. See the
<a href="pcrejit.html"><b>pcrejit</b></a>	<a href="pcrejit.html"><b>pcrejit</b></a>
documentation for more details.	documentation for more details.
</P>	</P>
<br><a name="SEC7" href="#TOC1">SAVING PRECOMPILED PATTERNS FOR LATER USE</a><br>	<br><a name="SEC9" href="#TOC1">SAVING PRECOMPILED PATTERNS FOR LATER USE</a><br>
<P>	<P>
The compiled form of a regular expression can be saved and re-used at a later	The compiled form of a regular expression can be saved and re-used at a later
time, possibly by a different program, and even on a host other than the one on	time, possibly by a different program, and even on a host other than the one on
which it was compiled. Details are given in the	which it was compiled. Details are given in the
<a href="pcreprecompile.html"><b>pcreprecompile</b></a>	<a href="pcreprecompile.html"><b>pcreprecompile</b></a>
documentation. However, compiling a regular expression with one version of PCRE	documentation, which includes a description of the
for use with a different version is not guaranteed to work and may cause	<b>pcre_pattern_to_host_byte_order()</b> function. However, compiling a regular
crashes.	expression with one version of PCRE for use with a different version is not
	guaranteed to work and may cause crashes.
</P>	</P>
<br><a name="SEC8" href="#TOC1">CHECKING BUILD-TIME OPTIONS</a><br>	<br><a name="SEC10" href="#TOC1">CHECKING BUILD-TIME OPTIONS</a><br>
<P>	<P>
<b>int pcre_config(int <i>what</i>, void *<i>where</i>);</b>	<b>int pcre_config(int <i>what</i>, void *<i>where</i>);</b>
</P>	</P>
Line 363 documentation has more details about these optional fe	Line 405 documentation has more details about these optional fe
<P>	<P>
The first argument for <b>pcre_config()</b> is an integer, specifying which	The first argument for <b>pcre_config()</b> is an integer, specifying which
information is required; the second argument is a pointer to a variable into	information is required; the second argument is a pointer to a variable into
which the information is placed. The following information is available:	which the information is placed. The returned value is zero on success, or the
	negative error code PCRE_ERROR_BADOPTION if the value in the first argument is
	not recognized. The following information is available:
<pre>	<pre>
PCRE_CONFIG_UTF8	PCRE_CONFIG_UTF8
</pre>	</pre>
The output is an integer that is set to one if UTF-8 support is available;	The output is an integer that is set to one if UTF-8 support is available;
otherwise it is set to zero.	otherwise it is set to zero. This value should normally be given to the 8-bit
	version of this function, <b>pcre_config()</b>. If it is given to the 16-bit
	or 32-bit version of this function, the result is PCRE_ERROR_BADOPTION.
<pre>	<pre>
	PCRE_CONFIG_UTF16
	</pre>
	The output is an integer that is set to one if UTF-16 support is available;
	otherwise it is set to zero. This value should normally be given to the 16-bit
	version of this function, <b>pcre16_config()</b>. If it is given to the 8-bit
	or 32-bit version of this function, the result is PCRE_ERROR_BADOPTION.
	<pre>
	PCRE_CONFIG_UTF32
	</pre>
	The output is an integer that is set to one if UTF-32 support is available;
	otherwise it is set to zero. This value should normally be given to the 32-bit
	version of this function, <b>pcre32_config()</b>. If it is given to the 8-bit
	or 16-bit version of this function, the result is PCRE_ERROR_BADOPTION.
	<pre>
PCRE_CONFIG_UNICODE_PROPERTIES	PCRE_CONFIG_UNICODE_PROPERTIES
</pre>	</pre>
The output is an integer that is set to one if support for Unicode character	The output is an integer that is set to one if support for Unicode character
Line 380 properties is available; otherwise it is set to zero.	Line 440 properties is available; otherwise it is set to zero.
The output is an integer that is set to one if support for just-in-time	The output is an integer that is set to one if support for just-in-time
compiling is available; otherwise it is set to zero.	compiling is available; otherwise it is set to zero.
<pre>	<pre>
	PCRE_CONFIG_JITTARGET
	</pre>
	The output is a pointer to a zero-terminated "const char *" string. If JIT
	support is available, the string contains the name of the architecture for
	which the JIT compiler is configured, for example "x86 32bit (little endian +
	unaligned)". If JIT support is not available, the result is NULL.
	<pre>
PCRE_CONFIG_NEWLINE	PCRE_CONFIG_NEWLINE
</pre>	</pre>
The output is an integer whose value specifies the default character sequence	The output is an integer whose value specifies the default character sequence
that is recognized as meaning "newline". The four values that are supported	that is recognized as meaning "newline". The values that are supported in
are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for ANYCRLF, and -1 for ANY.	ASCII/Unicode environments are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for
Though they are derived from ASCII, the same values are returned in EBCDIC	ANYCRLF, and -1 for ANY. In EBCDIC environments, CR, ANYCRLF, and ANY yield the
environments. The default should normally correspond to the standard sequence	same values. However, the value for LF is normally 21, though some EBCDIC
for your operating system.	environments use 37. The corresponding values for CRLF are 3349 and 3365. The
	default should normally correspond to the standard sequence for your operating
	system.
<pre>	<pre>
PCRE_CONFIG_BSR	PCRE_CONFIG_BSR
</pre>	</pre>
Line 399 or CRLF. The default can be overridden when a pattern	Line 468 or CRLF. The default can be overridden when a pattern
PCRE_CONFIG_LINK_SIZE	PCRE_CONFIG_LINK_SIZE
</pre>	</pre>
The output is an integer that contains the number of bytes used for internal	The output is an integer that contains the number of bytes used for internal
linkage in compiled regular expressions. The value is 2, 3, or 4. Larger values	linkage in compiled regular expressions. For the 8-bit library, the value can
allow larger regular expressions to be compiled, at the expense of slower	be 2, 3, or 4. For the 16-bit library, the value is either 2 or 4 and is still
matching. The default value of 2 is sufficient for all but the most massive	a number of bytes. For the 32-bit library, the value is either 2 or 4 and is
patterns, since it allows the compiled pattern to be up to 64K in size.	still a number of bytes. The default value of 2 is sufficient for all but the
	most massive patterns, since it allows the compiled pattern to be up to 64K in
	size. Larger values allow larger regular expressions to be compiled, at the
	expense of slower matching.
<pre>	<pre>
PCRE_CONFIG_POSIX_MALLOC_THRESHOLD	PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
</pre>	</pre>
Line 412 the	Line 484 the
<a href="pcreposix.html"><b>pcreposix</b></a>	<a href="pcreposix.html"><b>pcreposix</b></a>
documentation.	documentation.
<pre>	<pre>
	PCRE_CONFIG_PARENS_LIMIT
	</pre>
	The output is a long integer that gives the maximum depth of nesting of
	parentheses (of any kind) in a pattern. This limit is imposed to cap the amount
	of system stack used when a pattern is compiled. It is specified when PCRE is
	built; the default is 250.
	<pre>
PCRE_CONFIG_MATCH_LIMIT	PCRE_CONFIG_MATCH_LIMIT
</pre>	</pre>
The output is a long integer that gives the default limit for the number of	The output is a long integer that gives the default limit for the number of
Line 434 of recursive function calls. In this case, <b>pcre_sta	Line 513 of recursive function calls. In this case, <b>pcre_sta
<b>pcre_stack_free</b> are called to manage memory blocks on the heap, thus	<b>pcre_stack_free</b> are called to manage memory blocks on the heap, thus
avoiding the use of the stack.	avoiding the use of the stack.
</P>	</P>
<br><a name="SEC9" href="#TOC1">COMPILING A PATTERN</a><br>	<br><a name="SEC11" href="#TOC1">COMPILING A PATTERN</a><br>
<P>	<P>
<b>pcre pcre_compile(const char <i>pattern</i>, int <i>options</i>,</b>	<b>pcre pcre_compile(const char <i>pattern</i>, int <i>options</i>,</b>
<b>const char *<i>errptr</i>, int <i>erroffset</i>,</b>	<b> const char *<i>errptr</i>, int <i>erroffset</i>,</b>
<b>const unsigned char *<i>tableptr</i>);</b>	<b> const unsigned char *<i>tableptr</i>);</b>
	<br>
	<br>
<b>pcre pcre_compile2(const char <i>pattern</i>, int <i>options</i>,</b>	<b>pcre pcre_compile2(const char <i>pattern</i>, int <i>options</i>,</b>
<b>int *<i>errorcodeptr</i>,</b>	<b> int *<i>errorcodeptr</i>,</b>
<b>const char *<i>errptr</i>, int <i>erroffset</i>,</b>	<b> const char *<i>errptr</i>, int <i>erroffset</i>,</b>
<b>const unsigned char *<i>tableptr</i>);</b>	<b> const unsigned char *<i>tableptr</i>);</b>
</P>	</P>
<P>	<P>
Either of the functions <b>pcre_compile()</b> or <b>pcre_compile2()</b> can be	Either of the functions <b>pcre_compile()</b> or <b>pcre_compile2()</b> can be
Line 477 documentation). For those options that can be differen	Line 558 documentation). For those options that can be differen
the pattern, the contents of the <i>options</i> argument specifies their	the pattern, the contents of the <i>options</i> argument specifies their
settings at the start of compilation and execution. The PCRE_ANCHORED,	settings at the start of compilation and execution. The PCRE_ANCHORED,
PCRE_BSR_<i>xxx</i>, PCRE_NEWLINE_<i>xxx</i>, PCRE_NO_UTF8_CHECK, and	PCRE_BSR_<i>xxx</i>, PCRE_NEWLINE_<i>xxx</i>, PCRE_NO_UTF8_CHECK, and
PCRE_NO_START_OPT options can be set at the time of matching as well as at	PCRE_NO_START_OPTIMIZE options can be set at the time of matching as well as at
compile time.	compile time.
</P>	</P>
<P>	<P>
Line 486 Otherwise, if compilation of a pattern fails, <b>pcre_	Line 567 Otherwise, if compilation of a pattern fails, <b>pcre_
NULL, and sets the variable pointed to by <i>errptr</i> to point to a textual	NULL, and sets the variable pointed to by <i>errptr</i> to point to a textual
error message. This is a static string that is part of the library. You must	error message. This is a static string that is part of the library. You must
not try to free it. Normally, the offset from the start of the pattern to the	not try to free it. Normally, the offset from the start of the pattern to the
byte that was being processed when the error was discovered is placed in the	data unit that was being processed when the error was discovered is placed in
variable pointed to by <i>erroffset</i>, which must not be NULL (if it is, an	the variable pointed to by <i>erroffset</i>, which must not be NULL (if it is,
immediate error is given). However, for an invalid UTF-8 string, the offset is	an immediate error is given). However, for an invalid UTF-8 or UTF-16 string,
that of the first byte of the failing character. Also, some errors are not	the offset is that of the first data unit of the failing character.
detected until checks are carried out when the whole pattern has been scanned;
in these cases the offset passed back is the length of the pattern.
</P>	</P>
<P>	<P>
Note that the offset is in bytes, not characters, even in UTF-8 mode. It may	Some errors are not detected until the whole pattern has been scanned; in these
sometimes point into the middle of a UTF-8 character.	cases, the offset passed back is the length of the pattern. Note that the
	offset is in data units, not characters, even in a UTF mode. It may sometimes
	point into the middle of a UTF-8 or UTF-16 character.
</P>	</P>
<P>	<P>
If <b>pcre_compile2()</b> is used instead of <b>pcre_compile()</b>, and the	If <b>pcre_compile2()</b> is used instead of <b>pcre_compile()</b>, and the
Line 508 If the final argument, <i>tableptr</i>, is NULL, PCRE	Line 589 If the final argument, <i>tableptr</i>, is NULL, PCRE
character tables that are built when PCRE is compiled, using the default C	character tables that are built when PCRE is compiled, using the default C
locale. Otherwise, <i>tableptr</i> must be an address that is the result of a	locale. Otherwise, <i>tableptr</i> must be an address that is the result of a
call to <b>pcre_maketables()</b>. This value is stored with the compiled	call to <b>pcre_maketables()</b>. This value is stored with the compiled
pattern, and used again by <b>pcre_exec()</b>, unless another table pointer is	pattern, and used again by <b>pcre_exec()</b> and <b>pcre_dfa_exec()</b> when the
passed to it. For more discussion, see the section on locale support below.	pattern is matched. For more discussion, see the section on locale support
	below.
</P>	</P>
<P>	<P>
This code fragment shows a typical straightforward call to <b>pcre_compile()</b>:	This code fragment shows a typical straightforward call to <b>pcre_compile()</b>:
Line 594 documentation.	Line 676 documentation.
<pre>	<pre>
PCRE_EXTENDED	PCRE_EXTENDED
</pre>	</pre>
If this bit is set, whitespace data characters in the pattern are totally	If this bit is set, most white space characters in the pattern are totally
ignored except when escaped or inside a character class. Whitespace does not	ignored except when escaped or inside a character class. However, white space
include the VT character (code 11). In addition, characters between an	is not allowed within sequences such as (?> that introduce various
unescaped # outside a character class and the next newline, inclusive, are also	parenthesized subpatterns, nor within a numerical quantifier such as {1,3}.
ignored. This is equivalent to Perl's /x option, and it can be changed within a	However, ignorable white space is permitted between an item and a following
pattern by a (?x) option setting.	quantifier and between a quantifier and a following + that indicates
	possessiveness.
</P>	</P>
<P>	<P>
	White space did not used to include the VT character (code 11), because Perl
	did not treat this character as white space. However, Perl changed at release
	5.18, so PCRE followed at release 8.34, and VT is now treated as white space.
	</P>
	<P>
	PCRE_EXTENDED also causes characters between an unescaped # outside a character
	class and the next newline, inclusive, to be ignored. PCRE_EXTENDED is
	equivalent to Perl's /x option, and it can be changed within a pattern by a
	(?x) option setting.
	</P>
	<P>
Which characters are interpreted as newlines is controlled by the options	Which characters are interpreted as newlines is controlled by the options
passed to <b>pcre_compile()</b> or by a special sequence at the start of the	passed to <b>pcre_compile()</b> or by a special sequence at the start of the
pattern, as described in the section entitled	pattern, as described in the section entitled
Line 612 happen to represent a newline do not count.	Line 706 happen to represent a newline do not count.
</P>	</P>
<P>	<P>
This option makes it possible to include comments inside complicated patterns.	This option makes it possible to include comments inside complicated patterns.
Note, however, that this applies only to data characters. Whitespace characters	Note, however, that this applies only to data characters. White space characters
may never appear within special character sequences in a pattern, for example	may never appear within special character sequences in a pattern, for example
within the sequence (?( that introduces a conditional subpattern.	within the sequence (?( that introduces a conditional subpattern.
<pre>	<pre>
Line 669 binary zero character followed by z).	Line 763 binary zero character followed by z).
<pre>	<pre>
PCRE_MULTILINE	PCRE_MULTILINE
</pre>	</pre>
By default, PCRE treats the subject string as consisting of a single line of	By default, for the purposes of matching "start of line" and "end of line",
characters (even if it actually contains newlines). The "start of line"	PCRE treats the subject string as consisting of a single line of characters,
metacharacter (^) matches only at the start of the string, while the "end of	even if it actually contains newlines. The "start of line" metacharacter (^)
line" metacharacter ($) matches only at the end of the string, or before a	matches only at the start of the string, and the "end of line" metacharacter
terminating newline (unless PCRE_DOLLAR_ENDONLY is set). This is the same as	($) matches only at the end of the string, or before a terminating newline
Perl.	(except when PCRE_DOLLAR_ENDONLY is set). Note, however, that unless
	PCRE_DOTALL is set, the "any character" metacharacter (.) does not match at a
	newline. This behaviour (for ^, $, and dot) is the same as Perl.
</P>	</P>
<P>	<P>
When PCRE_MULTILINE it is set, the "start of line" and "end of line" constructs	When PCRE_MULTILINE it is set, the "start of line" and "end of line" constructs
Line 684 equivalent to Perl's /m option, and it can be changed	Line 780 equivalent to Perl's /m option, and it can be changed
(?m) option setting. If there are no newlines in a subject string, or no	(?m) option setting. If there are no newlines in a subject string, or no
occurrences of ^ or $ in a pattern, setting PCRE_MULTILINE has no effect.	occurrences of ^ or $ in a pattern, setting PCRE_MULTILINE has no effect.
<pre>	<pre>
	PCRE_NEVER_UTF
	</pre>
	This option locks out interpretation of the pattern as UTF-8 (or UTF-16 or
	UTF-32 in the 16-bit and 32-bit libraries). In particular, it prevents the
	creator of the pattern from switching to UTF interpretation by starting the
	pattern with (*UTF). This may be useful in applications that process patterns
	from external sources. The combination of PCRE_UTF8 and PCRE_NEVER_UTF also
	causes an error.
	<pre>
PCRE_NEWLINE_CR	PCRE_NEWLINE_CR
PCRE_NEWLINE_LF	PCRE_NEWLINE_LF
PCRE_NEWLINE_CRLF	PCRE_NEWLINE_CRLF
Line 696 indicated by a single character (CR or LF, respectivel	Line 801 indicated by a single character (CR or LF, respectivel
PCRE_NEWLINE_CRLF specifies that a newline is indicated by the two-character	PCRE_NEWLINE_CRLF specifies that a newline is indicated by the two-character
CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies that any of the three	CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies that any of the three
preceding sequences should be recognized. Setting PCRE_NEWLINE_ANY specifies	preceding sequences should be recognized. Setting PCRE_NEWLINE_ANY specifies
that any Unicode newline sequence should be recognized. The Unicode newline	that any Unicode newline sequence should be recognized.
sequences are the three just mentioned, plus the single characters VT (vertical	</P>
tab, U+000B), FF (formfeed, U+000C), NEL (next line, U+0085), LS (line	<P>
separator, U+2028), and PS (paragraph separator, U+2029). The last two are	In an ASCII/Unicode environment, the Unicode newline sequences are the three
	just mentioned, plus the single characters VT (vertical tab, U+000B), FF (form
	feed, U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS
	(paragraph separator, U+2029). For the 8-bit library, the last two are
recognized only in UTF-8 mode.	recognized only in UTF-8 mode.
</P>	</P>
<P>	<P>
	When PCRE is compiled to run in an EBCDIC (mainframe) environment, the code for
	CR is 0x0d, the same as ASCII. However, the character code for LF is normally
	0x15, though in some EBCDIC environments 0x25 is used. Whichever of these is
	not LF is made to correspond to Unicode's NEL character. EBCDIC codes are all
	less than 256. For more details, see the
	<a href="pcrebuild.html"><b>pcrebuild</b></a>
	documentation.
	</P>
	<P>
The newline setting in the options word uses three bits that are treated	The newline setting in the options word uses three bits that are treated
as a number, giving eight possibilities. Currently only six are used (default	as a number, giving eight possibilities. Currently only six are used (default
plus the five values above). This means that if you set more than one newline	plus the five values above). This means that if you set more than one newline
Line 712 other combinations may yield unused numbers and cause	Line 829 other combinations may yield unused numbers and cause
</P>	</P>
<P>	<P>
The only time that a line break in a pattern is specially recognized when	The only time that a line break in a pattern is specially recognized when
compiling is when PCRE_EXTENDED is set. CR and LF are whitespace characters,	compiling is when PCRE_EXTENDED is set. CR and LF are white space characters,
and so are ignored in this mode. Also, an unescaped # outside a character class	and so are ignored in this mode. Also, an unescaped # outside a character class
indicates a comment that lasts until after the next line break sequence. In	indicates a comment that lasts until after the next line break sequence. In
other circumstances, line break sequences in patterns are treated as literal	other circumstances, line break sequences in patterns are treated as literal
Line 730 were followed by ?: but named parentheses can still be	Line 847 were followed by ?: but named parentheses can still be
they acquire numbers in the usual way). There is no equivalent of this option	they acquire numbers in the usual way). There is no equivalent of this option
in Perl.	in Perl.
<pre>	<pre>
NO_START_OPTIMIZE	PCRE_NO_AUTO_POSSESS
</pre>	</pre>
	If this option is set, it disables "auto-possessification". This is an
	optimization that, for example, turns a+b into a++b in order to avoid
	backtracks into a+ that can never be successful. However, if callouts are in
	use, auto-possessification means that some of them are never taken. You can set
	this option if you want the matching functions to do a full unoptimized search
	and run all the callouts, but it is mainly provided for testing purposes.
	<pre>
	PCRE_NO_START_OPTIMIZE
	</pre>
This is an option that acts at matching time; that is, it is really an option	This is an option that acts at matching time; that is, it is really an option
for <b>pcre_exec()</b> or <b>pcre_dfa_exec()</b>. If it is set at compile time,	for <b>pcre_exec()</b> or <b>pcre_dfa_exec()</b>. If it is set at compile time,
it is remembered with the compiled pattern and assumed at matching time. For	it is remembered with the compiled pattern and assumed at matching time. This
details see the discussion of PCRE_NO_START_OPTIMIZE	is necessary if you want to use JIT execution, because the JIT compiler needs
	to know whether or not this option is set. For details see the discussion of
	PCRE_NO_START_OPTIMIZE
<a href="#execoptions">below.</a>	<a href="#execoptions">below.</a>
<pre>	<pre>
PCRE_UCP	PCRE_UCP
Line 760 with Perl. It can also be set by a (?U) option setting	Line 888 with Perl. It can also be set by a (?U) option setting
PCRE_UTF8	PCRE_UTF8
</pre>	</pre>
This option causes PCRE to regard both the pattern and the subject as strings	This option causes PCRE to regard both the pattern and the subject as strings
of UTF-8 characters instead of single-byte character strings. However, it is	of UTF-8 characters instead of single-byte strings. However, it is available
available only when PCRE is built to include UTF-8 support. If not, the use	only when PCRE is built to include UTF support. If not, the use of this option
of this option provokes an error. Details of how this option changes the	provokes an error. Details of how this option changes the behaviour of PCRE are
behaviour of PCRE are given in the	given in the
<a href="pcreunicode.html"><b>pcreunicode</b></a>	<a href="pcreunicode.html"><b>pcreunicode</b></a>
page.	page.
<pre>	<pre>
Line 771 page.	Line 899 page.
</pre>	</pre>
When PCRE_UTF8 is set, the validity of the pattern as a UTF-8 string is	When PCRE_UTF8 is set, the validity of the pattern as a UTF-8 string is
automatically checked. There is a discussion about the	automatically checked. There is a discussion about the
<a href="pcre.html#utf8strings">validity of UTF-8 strings</a>	<a href="pcreunicode.html#utf8strings">validity of UTF-8 strings</a>
in the main	in the
<a href="pcre.html"><b>pcre</b></a>	<a href="pcreunicode.html"><b>pcreunicode</b></a>
page. If an invalid UTF-8 sequence of bytes is found, <b>pcre_compile()</b>	page. If an invalid UTF-8 sequence is found, <b>pcre_compile()</b> returns an
returns an error. If you already know that your pattern is valid, and you want	error. If you already know that your pattern is valid, and you want to skip
to skip this check for performance reasons, you can set the PCRE_NO_UTF8_CHECK	this check for performance reasons, you can set the PCRE_NO_UTF8_CHECK option.
option. When it is set, the effect of passing an invalid UTF-8 string as a	When it is set, the effect of passing an invalid UTF-8 string as a pattern is
pattern is undefined. It may cause your program to crash. Note that this option	undefined. It may cause your program to crash or loop. Note that this option
can also be passed to <b>pcre_exec()</b> and <b>pcre_dfa_exec()</b>, to suppress	can also be passed to <b>pcre_exec()</b> and <b>pcre_dfa_exec()</b>, to suppress
the UTF-8 validity checking of subject strings.	the validity checking of subject strings only. If the same string is being
	matched many times, the option can be safely set for the second and subsequent
	matchings to improve performance.
</P>	</P>
<br><a name="SEC10" href="#TOC1">COMPILATION ERROR CODES</a><br>	<br><a name="SEC12" href="#TOC1">COMPILATION ERROR CODES</a><br>
<P>	<P>
The following table lists the error codes than may be returned by	The following table lists the error codes than may be returned by
<b>pcre_compile2()</b>, along with the error messages that may be returned by	<b>pcre_compile2()</b>, along with the error messages that may be returned by
both compiling functions. As PCRE has developed, some error codes have fallen	both compiling functions. Note that error messages are always 8-bit ASCII
out of use. To avoid confusion, they have not been re-used.	strings, even in 16-bit or 32-bit mode. As PCRE has developed, some error codes
	have fallen out of use. To avoid confusion, they have not been re-used.
<pre>	<pre>
0 no error	0 no error
1 \ at end of pattern	1 \ at end of pattern
Line 821 out of use. To avoid confusion, they have not been re-	Line 952 out of use. To avoid confusion, they have not been re-
29 (?R or (?[+-]digits must be followed by )	29 (?R or (?[+-]digits must be followed by )
30 unknown POSIX class name	30 unknown POSIX class name
31 POSIX collating elements are not supported	31 POSIX collating elements are not supported
32 this version of PCRE is not compiled with PCRE_UTF8 support	32 this version of PCRE is compiled without UTF support
33 [this code is not in use]	33 [this code is not in use]
34 character value in \x{...} sequence is too large	34 character value in \x{} or \o{} is too large
35 invalid condition (?(0)	35 invalid condition (?(0)
36 \C not allowed in lookbehind assertion	36 \C not allowed in lookbehind assertion
37 PCRE does not support \L, \l, \N{name}, \U, or \u	37 PCRE does not support \L, \l, \N{name}, \U, or \u
Line 833 out of use. To avoid confusion, they have not been re-	Line 964 out of use. To avoid confusion, they have not been re-
41 unrecognized character after (?P	41 unrecognized character after (?P
42 syntax error in subpattern name (missing terminator)	42 syntax error in subpattern name (missing terminator)
43 two named subpatterns have the same name	43 two named subpatterns have the same name
44 invalid UTF-8 string	44 invalid UTF-8 string (specifically UTF-8)
45 support for \P, \p, and \X has not been compiled	45 support for \P, \p, and \X has not been compiled
46 malformed \P or \p sequence	46 malformed \P or \p sequence
47 unknown property name after \P or \p	47 unknown property name after \P or \p
48 subpattern name is too long (maximum 32 characters)	48 subpattern name is too long (maximum 32 characters)
49 too many named subpatterns (maximum 10000)	49 too many named subpatterns (maximum 10000)
50 [this code is not in use]	50 [this code is not in use]
51 octal value is greater than \377 (not in UTF-8 mode)	51 octal value is greater than \377 in 8-bit non-UTF-8 mode
52 internal error: overran compiling workspace	52 internal error: overran compiling workspace
53 internal error: previously-checked referenced subpattern	53 internal error: previously-checked referenced subpattern
not found	not found
Line 851 out of use. To avoid confusion, they have not been re-	Line 982 out of use. To avoid confusion, they have not been re-
name/number or by a plain number	name/number or by a plain number
58 a numbered reference must not be zero	58 a numbered reference must not be zero
59 an argument is not allowed for (ACCEPT), (FAIL), or (*COMMIT)	59 an argument is not allowed for (ACCEPT), (FAIL), or (*COMMIT)
60 (*VERB) not recognized	60 (*VERB) not recognized or malformed
61 number is too big	61 number is too big
62 subpattern name expected	62 subpattern name expected
63 digit expected after (?+	63 digit expected after (?+
Line 859 out of use. To avoid confusion, they have not been re-	Line 990 out of use. To avoid confusion, they have not been re-
65 different names for subpatterns of the same number are	65 different names for subpatterns of the same number are
not allowed	not allowed
66 (*MARK) must have an argument	66 (*MARK) must have an argument
67 this version of PCRE is not compiled with PCRE_UCP support	67 this version of PCRE is not compiled with Unicode property
	support
68 \c must be followed by an ASCII character	68 \c must be followed by an ASCII character
69 \k is not followed by a braced, angle-bracketed, or quoted name	69 \k is not followed by a braced, angle-bracketed, or quoted name
	70 internal error: unknown opcode in find_fixedlength()
	71 \N is not supported in a class
	72 too many forward references
	73 disallowed Unicode code point (>= 0xd800 && <= 0xdfff)
	74 invalid UTF-16 string (specifically UTF-16)
	75 name is too long in (MARK), (PRUNE), (SKIP), or (THEN)
	76 character value in \u.... sequence is too large
	77 invalid UTF-32 string (specifically UTF-32)
	78 setting UTF is disabled by the application
	79 non-hex character in \x{} (closing brace missing?)
	80 non-octal character in \o{} (closing brace missing?)
	81 missing opening brace after \o
	82 parentheses are too deeply nested
	83 invalid range in character class
</pre>	</pre>
The numbers 32 and 10000 in errors 48 and 49 are defaults; different values may	The numbers 32 and 10000 in errors 48 and 49 are defaults; different values may
be used if the limits were changed when PCRE was built.	be used if the limits were changed when PCRE was built.
<a name="studyingapattern"></a></P>	<a name="studyingapattern"></a></P>
<br><a name="SEC11" href="#TOC1">STUDYING A PATTERN</a><br>	<br><a name="SEC13" href="#TOC1">STUDYING A PATTERN</a><br>
<P>	<P>
<b>pcre_extra pcre_study(const pcre <i>code</i>, int <i>options</i></b>	<b>pcre_extra pcre_study(const pcre <i>code</i>, int <i>options</i>,</b>
<b>const char **<i>errptr</i>);</b>	<b> const char **<i>errptr</i>);</b>
</P>	</P>
<P>	<P>
If a compiled pattern is going to be used several times, it is worth spending	If a compiled pattern is going to be used several times, it is worth spending
Line 890 in the section on matching a pattern.	Line 1036 in the section on matching a pattern.
</P>	</P>
<P>	<P>
If studying the pattern does not produce any useful information,	If studying the pattern does not produce any useful information,
<b>pcre_study()</b> returns NULL. In that circumstance, if the calling program	<b>pcre_study()</b> returns NULL by default. In that circumstance, if the
wants to pass any of the other fields to <b>pcre_exec()</b> or	calling program wants to pass any of the other fields to <b>pcre_exec()</b> or
<b>pcre_dfa_exec()</b>, it must set up its own <b>pcre_extra</b> block.	<b>pcre_dfa_exec()</b>, it must set up its own <b>pcre_extra</b> block. However,
	if <b>pcre_study()</b> is called with the PCRE_STUDY_EXTRA_NEEDED option, it
	returns a <b>pcre_extra</b> block even if studying did not find any additional
	information. It may still return NULL, however, if an error occurs in
	<b>pcre_study()</b>.
</P>	</P>
<P>	<P>
The second argument of <b>pcre_study()</b> contains option bits. There is only	The second argument of <b>pcre_study()</b> contains option bits. There are three
one option: PCRE_STUDY_JIT_COMPILE. If this is set, and the just-in-time	further options in addition to PCRE_STUDY_EXTRA_NEEDED:
compiler is available, the pattern is further compiled into machine code that	<pre>
executes much faster than the <b>pcre_exec()</b> matching function. If	PCRE_STUDY_JIT_COMPILE
the just-in-time compiler is not available, this option is ignored. All other	PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
bits in the <i>options</i> argument must be zero.	PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
	</pre>
	If any of these are set, and the just-in-time compiler is available, the
	pattern is further compiled into machine code that executes much faster than
	the <b>pcre_exec()</b> interpretive matching function. If the just-in-time
	compiler is not available, these options are ignored. All undefined bits in the
	<i>options</i> argument must be zero.
</P>	</P>
<P>	<P>
JIT compilation is a heavyweight optimization. It can take some time for	JIT compilation is a heavyweight optimization. It can take some time for
Line 925 When you are finished with a pattern, you can free the	Line 1081 When you are finished with a pattern, you can free the
study data by calling <b>pcre_free_study()</b>. This function was added to the	study data by calling <b>pcre_free_study()</b>. This function was added to the
API for release 8.20. For earlier versions, the memory could be freed with	API for release 8.20. For earlier versions, the memory could be freed with
<b>pcre_free()</b>, just like the pattern itself. This will still work in cases	<b>pcre_free()</b>, just like the pattern itself. This will still work in cases
where PCRE_STUDY_JIT_COMPILE is not used, but it is advisable to change to the	where JIT optimization is not used, but it is advisable to change to the new
new function when convenient.	function when convenient.
</P>	</P>
<P>	<P>
This is a typical way in which <b>pcre_study</b>() is used (except that in a	This is a typical way in which <b>pcre_study</b>() is used (except that in a
Line 949 real application there should be tests for errors):	Line 1105 real application there should be tests for errors):
Studying a pattern does two things: first, a lower bound for the length of	Studying a pattern does two things: first, a lower bound for the length of
subject string that is needed to match the pattern is computed. This does not	subject string that is needed to match the pattern is computed. This does not
mean that there are any strings of that length that match, but it does	mean that there are any strings of that length that match, but it does
guarantee that no shorter strings match. The value is used by	guarantee that no shorter strings match. The value is used to avoid wasting
<b>pcre_exec()</b> and <b>pcre_dfa_exec()</b> to avoid wasting time by trying to	time by trying to match strings that are shorter than the lower bound. You can
match strings that are shorter than the lower bound. You can find out the value	find out the value in a calling program via the <b>pcre_fullinfo()</b> function.
in a calling program via the <b>pcre_fullinfo()</b> function.
</P>	</P>
<P>	<P>
Studying a pattern is also useful for non-anchored patterns that do not have a	Studying a pattern is also useful for non-anchored patterns that do not have a
single fixed starting character. A bitmap of possible starting bytes is	single fixed starting character. A bitmap of possible starting bytes is
created. This speeds up finding a position in the subject at which to start	created. This speeds up finding a position in the subject at which to start
matching.	matching. (In 16-bit mode, the bitmap is used for 16-bit values less than 256.
	In 32-bit mode, the bitmap is used for 32-bit values less than 256.)
</P>	</P>
<P>	<P>
These two optimizations apply to both <b>pcre_exec()</b> and	These two optimizations apply to both <b>pcre_exec()</b> and
<b>pcre_dfa_exec()</b>. However, they are not used by <b>pcre_exec()</b> if	<b>pcre_dfa_exec()</b>, and the information is also used by the JIT compiler.
<b>pcre_study()</b> is called with the PCRE_STUDY_JIT_COMPILE option, and	The optimizations can be disabled by setting the PCRE_NO_START_OPTIMIZE option.
just-in-time compiling is successful. The optimizations can be disabled by	You might want to do this if your pattern contains callouts or (*MARK) and you
setting the PCRE_NO_START_OPTIMIZE option when calling <b>pcre_exec()</b> or	want to make use of these facilities in cases where matching fails.
<b>pcre_dfa_exec()</b>. You might want to do this if your pattern contains	</P>
callouts or (*MARK) (which cannot be handled by the JIT compiler), and you want	<P>
to make use of these facilities in cases where matching fails. See the	PCRE_NO_START_OPTIMIZE can be specified at either compile time or execution
discussion of PCRE_NO_START_OPTIMIZE	time. However, if PCRE_NO_START_OPTIMIZE is passed to <b>pcre_exec()</b>, (that
	is, after any JIT compilation has happened) JIT execution is disabled. For JIT
	execution to work with PCRE_NO_START_OPTIMIZE, the option must be set at
	compile time.
	</P>
	<P>
	There is a longer discussion of PCRE_NO_START_OPTIMIZE
<a href="#execoptions">below.</a>	<a href="#execoptions">below.</a>
<a name="localesupport"></a></P>	<a name="localesupport"></a></P>
<br><a name="SEC12" href="#TOC1">LOCALE SUPPORT</a><br>	<br><a name="SEC14" href="#TOC1">LOCALE SUPPORT</a><br>
<P>	<P>
PCRE handles caseless matching, and determines whether characters are letters,	PCRE handles caseless matching, and determines whether characters are letters,
digits, or whatever, by reference to a set of tables, indexed by character	digits, or whatever, by reference to a set of tables, indexed by character
value. When running in UTF-8 mode, this applies only to characters with codes	code point. When running in UTF-8 mode, or in the 16- or 32-bit libraries, this
less than 128. By default, higher-valued codes never match escapes such as \w	applies only to characters with code points less than 256. By default,
or \d, but they can be tested with \p if PCRE is built with Unicode character	higher-valued code points never match escapes such as \w or \d. However, if
property support. Alternatively, the PCRE_UCP option can be set at compile	PCRE is built with Unicode property support, all characters can be tested with
time; this causes \w and friends to use Unicode property support instead of	\p and \P, or, alternatively, the PCRE_UCP option can be set when a pattern
built-in tables. The use of locales with Unicode is discouraged. If you are	is compiled; this causes \w and friends to use Unicode property support
handling characters with codes greater than 128, you should either use UTF-8	instead of the built-in tables.
and Unicode, or use locales, but not try to mix the two.
</P>	</P>
<P>	<P>
	The use of locales with Unicode is discouraged. If you are handling characters
	with code points greater than 128, you should either use Unicode support, or
	use locales, but not try to mix the two.
	</P>
	<P>
PCRE contains an internal set of tables that are used when the final argument	PCRE contains an internal set of tables that are used when the final argument
of <b>pcre_compile()</b> is NULL. These are sufficient for many applications.	of <b>pcre_compile()</b> is NULL. These are sufficient for many applications.
Normally, the internal tables recognize only ASCII characters. However, when	Normally, the internal tables recognize only ASCII characters. However, when
Line 1001 for this locale support is expected to die away.	Line 1167 for this locale support is expected to die away.
<P>	<P>
External tables are built by calling the <b>pcre_maketables()</b> function,	External tables are built by calling the <b>pcre_maketables()</b> function,
which has no arguments, in the relevant locale. The result can then be passed	which has no arguments, in the relevant locale. The result can then be passed
to <b>pcre_compile()</b> or <b>pcre_exec()</b> as often as necessary. For	to <b>pcre_compile()</b> as often as necessary. For example, to build and use
example, to build and use tables that are appropriate for the French locale	tables that are appropriate for the French locale (where accented characters
(where accented characters with values greater than 128 are treated as letters),	with values greater than 128 are treated as letters), the following code could
the following code could be used:	be used:
<pre>	<pre>
setlocale(LC_CTYPE, "fr_FR");	setlocale(LC_CTYPE, "fr_FR");
tables = pcre_maketables();	tables = pcre_maketables();
Line 1022 needed.	Line 1188 needed.
<P>	<P>
The pointer that is passed to <b>pcre_compile()</b> is saved with the compiled	The pointer that is passed to <b>pcre_compile()</b> is saved with the compiled
pattern, and the same tables are used via this pointer by <b>pcre_study()</b>	pattern, and the same tables are used via this pointer by <b>pcre_study()</b>
and normally also by <b>pcre_exec()</b>. Thus, by default, for any single	and also by <b>pcre_exec()</b> and <b>pcre_dfa_exec()</b>. Thus, for any single
pattern, compilation, studying and matching all happen in the same locale, but	pattern, compilation, studying and matching all happen in the same locale, but
different patterns can be compiled in different locales.	different patterns can be processed in different locales.
</P>	</P>
<P>	<P>
It is possible to pass a table pointer or NULL (indicating the use of the	It is possible to pass a table pointer or NULL (indicating the use of the
internal tables) to <b>pcre_exec()</b>. Although not intended for this purpose,	internal tables) to <b>pcre_exec()</b> or <b>pcre_dfa_exec()</b> (see the
this facility could be used to match a pattern in a different locale from the	discussion below in the section on matching a pattern). This facility is
one in which it was compiled. Passing table pointers at run time is discussed	provided for use with pre-compiled patterns that have been saved and reloaded.
below in the section on matching a pattern.	Character tables are not saved with patterns, so if a non-standard table was
	used at compile time, it must be provided again when the reloaded pattern is
	matched. Attempting to use this facility to match a pattern in a different
	locale from the one in which it was compiled is likely to lead to anomalous
	(usually incorrect) results.
<a name="infoaboutpattern"></a></P>	<a name="infoaboutpattern"></a></P>
<br><a name="SEC13" href="#TOC1">INFORMATION ABOUT A PATTERN</a><br>	<br><a name="SEC15" href="#TOC1">INFORMATION ABOUT A PATTERN</a><br>
<P>	<P>
<b>int pcre_fullinfo(const pcre <i>code</i>, const pcre_extra <i>extra</i>,</b>	<b>int pcre_fullinfo(const pcre <i>code</i>, const pcre_extra <i>extra</i>,</b>
<b>int <i>what</i>, void *<i>where</i>);</b>	<b> int <i>what</i>, void *<i>where</i>);</b>
</P>	</P>
<P>	<P>
The <b>pcre_fullinfo()</b> function returns information about a compiled	The <b>pcre_fullinfo()</b> function returns information about a compiled
pattern. It replaces the obsolete <b>pcre_info()</b> function, which is	pattern. It replaces the <b>pcre_info()</b> function, which was removed from the
nevertheless retained for backwards compability (and is documented below).	library at version 8.30, after more than 10 years of obsolescence.
</P>	</P>
<P>	<P>
The first argument for <b>pcre_fullinfo()</b> is a pointer to the compiled	The first argument for <b>pcre_fullinfo()</b> is a pointer to the compiled
Line 1051 information is required, and the fourth argument is a	Line 1221 information is required, and the fourth argument is a
to receive the data. The yield of the function is zero for success, or one of	to receive the data. The yield of the function is zero for success, or one of
the following negative numbers:	the following negative numbers:
<pre>	<pre>
PCRE_ERROR_NULL the argument <i>code</i> was NULL	PCRE_ERROR_NULL the argument <i>code</i> was NULL
the argument <i>where</i> was NULL	the argument <i>where</i> was NULL
PCRE_ERROR_BADMAGIC the "magic number" was not found	PCRE_ERROR_BADMAGIC the "magic number" was not found
PCRE_ERROR_BADOPTION the value of <i>what</i> was invalid	PCRE_ERROR_BADENDIANNESS the pattern was compiled with different
	endianness
	PCRE_ERROR_BADOPTION the value of <i>what</i> was invalid
	PCRE_ERROR_UNSET the requested field is not set
</pre>	</pre>
The "magic number" is placed at the start of each compiled pattern as an simple	The "magic number" is placed at the start of each compiled pattern as an simple
check against passing an arbitrary memory pointer. Here is a typical call of	check against passing an arbitrary memory pointer. The endianness error can
<b>pcre_fullinfo()</b>, to obtain the length of the compiled pattern:	occur if a compiled pattern is saved and reloaded on a different host. Here is
	a typical call of <b>pcre_fullinfo()</b>, to obtain the length of the compiled
	pattern:
<pre>	<pre>
int rc;	int rc;
size_t length;	size_t length;
Line 1092 a NULL table pointer.	Line 1267 a NULL table pointer.
<pre>	<pre>
PCRE_INFO_FIRSTBYTE	PCRE_INFO_FIRSTBYTE
</pre>	</pre>
Return information about the first byte of any matched string, for a	Return information about the first data unit of any matched string, for a
non-anchored pattern. The fourth argument should point to an <b>int</b>	non-anchored pattern. (The name of this option refers to the 8-bit library,
variable. (This option used to be called PCRE_INFO_FIRSTCHAR; the old name is	where data units are bytes.) The fourth argument should point to an <b>int</b>
still recognized for backwards compatibility.)	variable.
</P>	</P>
<P>	<P>
If there is a fixed first byte, for example, from a pattern such as	If there is a fixed first value, for example, the letter "c" from a pattern
(cat\|cow\|coyote), its value is returned. Otherwise, if either	such as (cat\|cow\|coyote), its value is returned. In the 8-bit library, the
	value is always less than 256. In the 16-bit library the value can be up to
	0xffff. In the 32-bit library the value can be up to 0x10ffff.
	</P>
	<P>
	If there is no fixed first value, and if either
<br>	<br>
<br>	<br>
(a) the pattern was compiled with the PCRE_MULTILINE option, and every branch	(a) the pattern was compiled with the PCRE_MULTILINE option, and every branch
Line 1113 starts with "^", or	Line 1293 starts with "^", or
-1 is returned, indicating that the pattern matches only at the start of a	-1 is returned, indicating that the pattern matches only at the start of a
subject string or after any newline within the string. Otherwise -2 is	subject string or after any newline within the string. Otherwise -2 is
returned. For anchored patterns, -2 is returned.	returned. For anchored patterns, -2 is returned.
	</P>
	<P>
	Since for the 32-bit library using the non-UTF-32 mode, this function is unable
	to return the full 32-bit range of the character, this value is deprecated;
	instead the PCRE_INFO_FIRSTCHARACTERFLAGS and PCRE_INFO_FIRSTCHARACTER values
	should be used.
<pre>	<pre>
PCRE_INFO_FIRSTTABLE	PCRE_INFO_FIRSTTABLE
</pre>	</pre>
If the pattern was studied, and this resulted in the construction of a 256-bit	If the pattern was studied, and this resulted in the construction of a 256-bit
table indicating a fixed set of bytes for the first byte in any matching	table indicating a fixed set of values for the first data unit in any matching
string, a pointer to the table is returned. Otherwise NULL is returned. The	string, a pointer to the table is returned. Otherwise NULL is returned. The
fourth argument should point to an <b>unsigned char *</b> variable.	fourth argument should point to an <b>unsigned char *</b> variable.
<pre>	<pre>
Line 1135 Return 1 if the (?J) or (?-J) option setting is used i	Line 1321 Return 1 if the (?J) or (?-J) option setting is used i
<pre>	<pre>
PCRE_INFO_JIT	PCRE_INFO_JIT
</pre>	</pre>
Return 1 if the pattern was studied with the PCRE_STUDY_JIT_COMPILE option, and	Return 1 if the pattern was studied with one of the JIT options, and
just-in-time compiling was successful. The fourth argument should point to an	just-in-time compiling was successful. The fourth argument should point to an
<b>int</b> variable. A return value of 0 means that JIT support is not available	<b>int</b> variable. A return value of 0 means that JIT support is not available
in this version of PCRE, or that the pattern was not studied with the	in this version of PCRE, or that the pattern was not studied with a JIT option,
PCRE_STUDY_JIT_COMPILE option, or that the JIT compiler could not handle this	or that the JIT compiler could not handle this particular pattern. See the
particular pattern. See the
<a href="pcrejit.html"><b>pcrejit</b></a>	<a href="pcrejit.html"><b>pcrejit</b></a>
documentation for details of what can and cannot be handled.	documentation for details of what can and cannot be handled.
<pre>	<pre>
PCRE_INFO_JITSIZE	PCRE_INFO_JITSIZE
</pre>	</pre>
If the pattern was successfully studied with the PCRE_STUDY_JIT_COMPILE option,	If the pattern was successfully studied with a JIT option, return the size of
return the size of the JIT compiled code, otherwise return zero. The fourth	the JIT compiled code, otherwise return zero. The fourth argument should point
argument should point to a <b>size_t</b> variable.	to a <b>size_t</b> variable.
<pre>	<pre>
PCRE_INFO_LASTLITERAL	PCRE_INFO_LASTLITERAL
</pre>	</pre>
Return the value of the rightmost literal byte that must exist in any matched	Return the value of the rightmost literal data unit that must exist in any
string, other than at its start, if such a byte has been recorded. The fourth	matched string, other than at its start, if such a value has been recorded. The
argument should point to an <b>int</b> variable. If there is no such byte, -1 is	fourth argument should point to an <b>int</b> variable. If there is no such
returned. For anchored patterns, a last literal byte is recorded only if it	value, -1 is returned. For anchored patterns, a last literal value is recorded
follows something of variable length. For example, for the pattern	only if it follows something of variable length. For example, for the pattern
/^a\d+z\d+/ the returned value is "z", but for /^a\dz\d/ the returned value	/^a\d+z\d+/ the returned value is "z", but for /^a\dz\d/ the returned value
is -1.	is -1.
	</P>
	<P>
	Since for the 32-bit library using the non-UTF-32 mode, this function is unable
	to return the full 32-bit range of characters, this value is deprecated;
	instead the PCRE_INFO_REQUIREDCHARFLAGS and PCRE_INFO_REQUIREDCHAR values should
	be used.
<pre>	<pre>
	PCRE_INFO_MATCH_EMPTY
	</pre>
	Return 1 if the pattern can match an empty string, otherwise 0. The fourth
	argument should point to an <b>int</b> variable.
	<pre>
	PCRE_INFO_MATCHLIMIT
	</pre>
	If the pattern set a match limit by including an item of the form
	(*LIMIT_MATCH=nnnn) at the start, the value is returned. The fourth argument
	should point to an unsigned 32-bit integer. If no such value has been set, the
	call to <b>pcre_fullinfo()</b> returns the error PCRE_ERROR_UNSET.
	<pre>
	PCRE_INFO_MAXLOOKBEHIND
	</pre>
	Return the number of characters (NB not data units) in the longest lookbehind
	assertion in the pattern. This information is useful when doing multi-segment
	matching using the partial matching facilities. Note that the simple assertions
	\b and \B require a one-character lookbehind. \A also registers a
	one-character lookbehind, though it does not actually inspect the previous
	character. This is to ensure that at least one character from the old segment
	is retained when a new segment is processed. Otherwise, if there are no
	lookbehinds in the pattern, \A might match incorrectly at the start of a new
	segment.
	<pre>
PCRE_INFO_MINLENGTH	PCRE_INFO_MINLENGTH
</pre>	</pre>
If the pattern was studied and a minimum length for matching subject strings	If the pattern was studied and a minimum length for matching subject strings
was computed, its value is returned. Otherwise the returned value is -1. The	was computed, its value is returned. Otherwise the returned value is -1. The
value is a number of characters, not bytes (this may be relevant in UTF-8	value is a number of characters, which in UTF mode may be different from the
mode). The fourth argument should point to an <b>int</b> variable. A	number of data units. The fourth argument should point to an <b>int</b>
non-negative value is a lower bound to the length of any matching string. There	variable. A non-negative value is a lower bound to the length of any matching
may not be any strings of that length that do actually match, but every string	string. There may not be any strings of that length that do actually match, but
that does match is at least that long.	every string that does match is at least that long.
<pre>	<pre>
PCRE_INFO_NAMECOUNT	PCRE_INFO_NAMECOUNT
PCRE_INFO_NAMEENTRYSIZE	PCRE_INFO_NAMEENTRYSIZE
Line 1189 The map consists of a number of fixed-size entries. PC	Line 1404 The map consists of a number of fixed-size entries. PC
the number of entries, and PCRE_INFO_NAMEENTRYSIZE gives the size of each	the number of entries, and PCRE_INFO_NAMEENTRYSIZE gives the size of each
entry; both of these return an <b>int</b> value. The entry size depends on the	entry; both of these return an <b>int</b> value. The entry size depends on the
length of the longest name. PCRE_INFO_NAMETABLE returns a pointer to the first	length of the longest name. PCRE_INFO_NAMETABLE returns a pointer to the first
entry of the table (a pointer to <b>char</b>). The first two bytes of each entry	entry of the table. This is a pointer to <b>char</b> in the 8-bit library, where
are the number of the capturing parenthesis, most significant byte first. The	the first two bytes of each entry are the number of the capturing parenthesis,
rest of the entry is the corresponding name, zero terminated.	most significant byte first. In the 16-bit library, the pointer points to
	16-bit data units, the first of which contains the parenthesis number. In the
	32-bit library, the pointer points to 32-bit data units, the first of which
	contains the parenthesis number. The rest of the entry is the corresponding
	name, zero terminated.
</P>	</P>
<P>	<P>
The names are in alphabetical order. Duplicate names may appear if (?\| is used	The names are in alphabetical order. If (?\| is used to create multiple groups
to create multiple groups with the same number, as described in the	with the same number, as described in the
<a href="pcrepattern.html#dupsubpatternnumber">section on duplicate subpattern numbers</a>	<a href="pcrepattern.html#dupsubpatternnumber">section on duplicate subpattern numbers</a>
in the	in the
<a href="pcrepattern.html"><b>pcrepattern</b></a>	<a href="pcrepattern.html"><b>pcrepattern</b></a>
page. Duplicate names for subpatterns with different numbers are permitted only	page, the groups may be given the same name, but there is only one entry in the
if PCRE_DUPNAMES is set. In all cases of duplicate names, they appear in the	table. Different names for groups of the same number are not permitted.
table in the order in which they were found in the pattern. In the absence of	Duplicate names for subpatterns with different numbers are permitted,
(?\| this is the order of increasing number; when (?\| is used this is not	but only if PCRE_DUPNAMES is set. They appear in the table in the order in
necessarily the case because later subpatterns may have lower numbers.	which they were found in the pattern. In the absence of (?\| this is the order
	of increasing number; when (?\| is used this is not necessarily the case because
	later subpatterns may have lower numbers.
</P>	</P>
<P>	<P>
As a simple example of the name/number table, consider the following pattern	As a simple example of the name/number table, consider the following pattern
(assume PCRE_EXTENDED is set, so white space - including newlines - is	after compilation by the 8-bit library (assume PCRE_EXTENDED is set, so white
ignored):	space - including newlines - is ignored):
<pre>	<pre>
(?<date> (?<year>(\d\d)?\d\d) - (?<month>\d\d) - (?<day>\d\d) )	(?<date> (?<year>(\d\d)?\d\d) - (?<month>\d\d) - (?<day>\d\d) )
</pre>	</pre>
Line 1256 alternatives begin with one of the following:	Line 1477 alternatives begin with one of the following:
For such patterns, the PCRE_ANCHORED bit is set in the options returned by	For such patterns, the PCRE_ANCHORED bit is set in the options returned by
<b>pcre_fullinfo()</b>.	<b>pcre_fullinfo()</b>.
<pre>	<pre>
	PCRE_INFO_RECURSIONLIMIT
	</pre>
	If the pattern set a recursion limit by including an item of the form
	(*LIMIT_RECURSION=nnnn) at the start, the value is returned. The fourth
	argument should point to an unsigned 32-bit integer. If no such value has been
	set, the call to <b>pcre_fullinfo()</b> returns the error PCRE_ERROR_UNSET.
	<pre>
PCRE_INFO_SIZE	PCRE_INFO_SIZE
</pre>	</pre>
Return the size of the compiled pattern. The fourth argument should point to a	Return the size of the compiled pattern in bytes (for all three libraries). The
<b>size_t</b> variable. This value does not include the size of the <b>pcre</b>	fourth argument should point to a <b>size_t</b> variable. This value does not
structure that is returned by <b>pcre_compile()</b>. The value that is passed as	include the size of the <b>pcre</b> structure that is returned by
the argument to <b>pcre_malloc()</b> when <b>pcre_compile()</b> is getting memory	<b>pcre_compile()</b>. The value that is passed as the argument to
in which to place the compiled data is the value returned by this option plus	<b>pcre_malloc()</b> when <b>pcre_compile()</b> is getting memory in which to
the size of the <b>pcre</b> structure. Studying a compiled pattern, with or	place the compiled data is the value returned by this option plus the size of
without JIT, does not alter the value returned by this option.	the <b>pcre</b> structure. Studying a compiled pattern, with or without JIT,
	does not alter the value returned by this option.
<pre>	<pre>
PCRE_INFO_STUDYSIZE	PCRE_INFO_STUDYSIZE
</pre>	</pre>
Return the size of the data block pointed to by the <i>study_data</i> field in a	Return the size in bytes (for all three libraries) of the data block pointed to
<b>pcre_extra</b> block. If <b>pcre_extra</b> is NULL, or there is no study data,	by the <i>study_data</i> field in a <b>pcre_extra</b> block. If <b>pcre_extra</b>
zero is returned. The fourth argument should point to a <b>size_t</b> variable.	is NULL, or there is no study data, zero is returned. The fourth argument
The <i>study_data</i> field is set by <b>pcre_study()</b> to record information	should point to a <b>size_t</b> variable. The <i>study_data</i> field is set by
that will speed up matching (see the section entitled	<b>pcre_study()</b> to record information that will speed up matching (see the
	section entitled
<a href="#studyingapattern">"Studying a pattern"</a>	<a href="#studyingapattern">"Studying a pattern"</a>
above). The format of the <i>study_data</i> block is private, but its length	above). The format of the <i>study_data</i> block is private, but its length
is made available via this option so that it can be saved and restored (see the	is made available via this option so that it can be saved and restored (see the
<a href="pcreprecompile.html"><b>pcreprecompile</b></a>	<a href="pcreprecompile.html"><b>pcreprecompile</b></a>
documentation for details).	documentation for details).
	<pre>
	PCRE_INFO_FIRSTCHARACTERFLAGS
	</pre>
	Return information about the first data unit of any matched string, for a
	non-anchored pattern. The fourth argument should point to an <b>int</b>
	variable.
</P>	</P>
<br><a name="SEC14" href="#TOC1">OBSOLETE INFO FUNCTION</a><br>
<P>	<P>
<b>int pcre_info(const pcre <i>code</i>, int <i>optptr</i>, int</b>	If there is a fixed first value, for example, the letter "c" from a pattern
<b>*<i>firstcharptr</i>);</b>	such as (cat\|cow\|coyote), 1 is returned, and the character value can be
	retrieved using PCRE_INFO_FIRSTCHARACTER.
</P>	</P>
<P>	<P>
The <b>pcre_info()</b> function is now obsolete because its interface is too	If there is no fixed first value, and if either
restrictive to return all the available data about a compiled pattern. New	<br>
programs should use <b>pcre_fullinfo()</b> instead. The yield of	<br>
<b>pcre_info()</b> is the number of capturing subpatterns, or one of the	(a) the pattern was compiled with the PCRE_MULTILINE option, and every branch
following negative numbers:	starts with "^", or
	<br>
	<br>
	(b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not set
	(if it were set, the pattern would be anchored),
	<br>
	<br>
	2 is returned, indicating that the pattern matches only at the start of a
	subject string or after any newline within the string. Otherwise 0 is
	returned. For anchored patterns, 0 is returned.
<pre>	<pre>
PCRE_ERROR_NULL the argument <i>code</i> was NULL	PCRE_INFO_FIRSTCHARACTER
PCRE_ERROR_BADMAGIC the "magic number" was not found
</pre>	</pre>
If the <i>optptr</i> argument is not NULL, a copy of the options with which the	Return the fixed first character value in the situation where
pattern was compiled is placed in the integer it points to (see	PCRE_INFO_FIRSTCHARACTERFLAGS returns 1; otherwise return 0. The fourth
PCRE_INFO_OPTIONS above).	argument should point to an <b>uint_t</b> variable.
</P>	</P>
<P>	<P>
If the pattern is not anchored and the <i>firstcharptr</i> argument is not NULL,	In the 8-bit library, the value is always less than 256. In the 16-bit library
it is used to pass back information about the first character of any matched	the value can be up to 0xffff. In the 32-bit library in UTF-32 mode the value
string (see PCRE_INFO_FIRSTBYTE above).	can be up to 0x10ffff, and up to 0xffffffff when not using UTF-32 mode.
	<pre>
	PCRE_INFO_REQUIREDCHARFLAGS
	</pre>
	Returns 1 if there is a rightmost literal data unit that must exist in any
	matched string, other than at its start. The fourth argument should point to
	an <b>int</b> variable. If there is no such value, 0 is returned. If returning
	1, the character value itself can be retrieved using PCRE_INFO_REQUIREDCHAR.
</P>	</P>
<br><a name="SEC15" href="#TOC1">REFERENCE COUNTS</a><br>
<P>	<P>
	For anchored patterns, a last literal value is recorded only if it follows
	something of variable length. For example, for the pattern /^a\d+z\d+/ the
	returned value 1 (with "z" returned from PCRE_INFO_REQUIREDCHAR), but for
	/^a\dz\d/ the returned value is 0.
	<pre>
	PCRE_INFO_REQUIREDCHAR
	</pre>
	Return the value of the rightmost literal data unit that must exist in any
	matched string, other than at its start, if such a value has been recorded. The
	fourth argument should point to an <b>uint32_t</b> variable. If there is no such
	value, 0 is returned.
	</P>
	<br><a name="SEC16" href="#TOC1">REFERENCE COUNTS</a><br>
	<P>
<b>int pcre_refcount(pcre *<i>code</i>, int <i>adjust</i>);</b>	<b>int pcre_refcount(pcre *<i>code</i>, int <i>adjust</i>);</b>
</P>	</P>
<P>	<P>
Line 1327 Except when it is zero, the reference count is not cor	Line 1591 Except when it is zero, the reference count is not cor
pattern is compiled on one host and then transferred to a host whose byte-order	pattern is compiled on one host and then transferred to a host whose byte-order
is different. (This seems a highly unlikely scenario.)	is different. (This seems a highly unlikely scenario.)
</P>	</P>
<br><a name="SEC16" href="#TOC1">MATCHING A PATTERN: THE TRADITIONAL FUNCTION</a><br>	<br><a name="SEC17" href="#TOC1">MATCHING A PATTERN: THE TRADITIONAL FUNCTION</a><br>
<P>	<P>
<b>int pcre_exec(const pcre <i>code</i>, const pcre_extra <i>extra</i>,</b>	<b>int pcre_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> 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>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>);</b>
</P>	</P>
<P>	<P>
The function <b>pcre_exec()</b> is called to match a subject string against a	The function <b>pcre_exec()</b> is called to match a subject string against a
Line 1392 fields (not necessarily in this order):	Line 1656 fields (not necessarily in this order):
const unsigned char *<i>tables</i>;	const unsigned char *<i>tables</i>;
unsigned char **<i>mark</i>;	unsigned char **<i>mark</i>;
</pre>	</pre>
The <i>flags</i> field is a bitmap that specifies which of the other fields	In the 16-bit version of this structure, the <i>mark</i> field has type
are set. The flag bits are:	"PCRE_UCHAR16 **".
	<br>
	<br>
	In the 32-bit version of this structure, the <i>mark</i> field has type
	"PCRE_UCHAR32 **".
	</P>
	<P>
	The <i>flags</i> field is used to specify which of the other fields are set. The
	flag bits are:
<pre>	<pre>
PCRE_EXTRA_STUDY_DATA	PCRE_EXTRA_CALLOUT_DATA
PCRE_EXTRA_EXECUTABLE_JIT	PCRE_EXTRA_EXECUTABLE_JIT
	PCRE_EXTRA_MARK
PCRE_EXTRA_MATCH_LIMIT	PCRE_EXTRA_MATCH_LIMIT
PCRE_EXTRA_MATCH_LIMIT_RECURSION	PCRE_EXTRA_MATCH_LIMIT_RECURSION
PCRE_EXTRA_CALLOUT_DATA	PCRE_EXTRA_STUDY_DATA
PCRE_EXTRA_TABLES	PCRE_EXTRA_TABLES
PCRE_EXTRA_MARK
</pre>	</pre>
Other flag bits should be set to zero. The <i>study_data</i> field and sometimes	Other flag bits should be set to zero. The <i>study_data</i> field and sometimes
the <i>executable_jit</i> field are set in the <b>pcre_extra</b> block that is	the <i>executable_jit</i> field are set in the <b>pcre_extra</b> block that is
returned by <b>pcre_study()</b>, together with the appropriate flag bits. You	returned by <b>pcre_study()</b>, together with the appropriate flag bits. You
should not set these yourself, but you may add to the block by setting the	should not set these yourself, but you may add to the block by setting other
other fields and their corresponding flag bits.	fields and their corresponding flag bits.
</P>	</P>
<P>	<P>
The <i>match_limit</i> field provides a means of preventing PCRE from using up a	The <i>match_limit</i> field provides a means of preventing PCRE from using up a
Line 1425 in the subject string.	Line 1697 in the subject string.
</P>	</P>
<P>	<P>
When <b>pcre_exec()</b> is called with a pattern that was successfully studied	When <b>pcre_exec()</b> is called with a pattern that was successfully studied
with the PCRE_STUDY_JIT_COMPILE option, the way that the matching is executed	with a JIT option, the way that the matching is executed is entirely different.
is entirely different. However, there is still the possibility of runaway	However, there is still the possibility of runaway matching that goes on for a
matching that goes on for a very long time, and so the <i>match_limit</i> value	very long time, and so the <i>match_limit</i> value is also used in this case
is also used in this case (but in a different way) to limit how long the	(but in a different way) to limit how long the matching can continue.
matching can continue.
</P>	</P>
<P>	<P>
The default value for the limit can be set when PCRE is built; the default	The default value for the limit can be set when PCRE is built; the default
Line 1440 the <i>flags</i> field. If the limit is exceeded, <b>p	Line 1711 the <i>flags</i> field. If the limit is exceeded, <b>p
PCRE_ERROR_MATCHLIMIT.	PCRE_ERROR_MATCHLIMIT.
</P>	</P>
<P>	<P>
	A value for the match limit may also be supplied by an item at the start of a
	pattern of the form
	<pre>
	(*LIMIT_MATCH=d)
	</pre>
	where d is a decimal number. However, such a setting is ignored unless d is
	less than the limit set by the caller of <b>pcre_exec()</b> or, if no such limit
	is set, less than the default.
	</P>
	<P>
The <i>match_limit_recursion</i> field is similar to <i>match_limit</i>, but	The <i>match_limit_recursion</i> field is similar to <i>match_limit</i>, but
instead of limiting the total number of times that <b>match()</b> is called, it	instead of limiting the total number of times that <b>match()</b> is called, it
limits the depth of recursion. The recursion depth is a smaller number than the	limits the depth of recursion. The recursion depth is a smaller number than the
Line 1450 This limit is of use only if it is set smaller than <i	Line 1731 This limit is of use only if it is set smaller than <i
Limiting the recursion depth limits the amount of machine stack that can be	Limiting the recursion depth limits the amount of machine stack that can be
used, or, when PCRE has been compiled to use memory on the heap instead of the	used, or, when PCRE has been compiled to use memory on the heap instead of the
stack, the amount of heap memory that can be used. This limit is not relevant,	stack, the amount of heap memory that can be used. This limit is not relevant,
and is ignored, if the pattern was successfully studied with	and is ignored, when matching is done using JIT compiled code.
PCRE_STUDY_JIT_COMPILE.
</P>	</P>
<P>	<P>
The default value for <i>match_limit_recursion</i> can be set when PCRE is	The default value for <i>match_limit_recursion</i> can be set when PCRE is
Line 1462 PCRE_EXTRA_MATCH_LIMIT_RECURSION is set in the <i>flag	Line 1742 PCRE_EXTRA_MATCH_LIMIT_RECURSION is set in the <i>flag
is exceeded, <b>pcre_exec()</b> returns PCRE_ERROR_RECURSIONLIMIT.	is exceeded, <b>pcre_exec()</b> returns PCRE_ERROR_RECURSIONLIMIT.
</P>	</P>
<P>	<P>
	A value for the recursion limit may also be supplied by an item at the start of
	a pattern of the form
	<pre>
	(*LIMIT_RECURSION=d)
	</pre>
	where d is a decimal number. However, such a setting is ignored unless d is
	less than the limit set by the caller of <b>pcre_exec()</b> or, if no such limit
	is set, less than the default.
	</P>
	<P>
The <i>callout_data</i> field is used in conjunction with the "callout" feature,	The <i>callout_data</i> field is used in conjunction with the "callout" feature,
and is described in the	and is described in the
<a href="pcrecallout.html"><b>pcrecallout</b></a>	<a href="pcrecallout.html"><b>pcrecallout</b></a>
documentation.	documentation.
</P>	</P>
<P>	<P>
The <i>tables</i> field is used to pass a character tables pointer to	The <i>tables</i> field is provided for use with patterns that have been
<b>pcre_exec()</b>; this overrides the value that is stored with the compiled	pre-compiled using custom character tables, saved to disc or elsewhere, and
pattern. A non-NULL value is stored with the compiled pattern only if custom	then reloaded, because the tables that were used to compile a pattern are not
tables were supplied to <b>pcre_compile()</b> via its <i>tableptr</i> argument.	saved with it. See the
If NULL is passed to <b>pcre_exec()</b> using this mechanism, it forces PCRE's
internal tables to be used. This facility is helpful when re-using patterns
that have been saved after compiling with an external set of tables, because
the external tables might be at a different address when <b>pcre_exec()</b> is
called. See the
<a href="pcreprecompile.html"><b>pcreprecompile</b></a>	<a href="pcreprecompile.html"><b>pcreprecompile</b></a>
documentation for a discussion of saving compiled patterns for later use.	documentation for a discussion of saving compiled patterns for later use. If
	NULL is passed using this mechanism, it forces PCRE's internal tables to be
	used.
</P>	</P>
<P>	<P>
	<b>Warning:</b> The tables that <b>pcre_exec()</b> uses must be the same as those
	that were used when the pattern was compiled. If this is not the case, the
	behaviour of <b>pcre_exec()</b> is undefined. Therefore, when a pattern is
	compiled and matched in the same process, this field should never be set. In
	this (the most common) case, the correct table pointer is automatically passed
	with the compiled pattern from <b>pcre_compile()</b> to <b>pcre_exec()</b>.
	</P>
	<P>
If PCRE_EXTRA_MARK is set in the <i>flags</i> field, the <i>mark</i> field must	If PCRE_EXTRA_MARK is set in the <i>flags</i> field, the <i>mark</i> field must
be set to point to a <b>char *</b> variable. If the pattern contains any	be set to point to a suitable variable. If the pattern contains any
backtracking control verbs such as (*MARK:NAME), and the execution ends up with	backtracking control verbs such as (*MARK:NAME), and the execution ends up with
a name to pass back, a pointer to the name string (zero terminated) is placed	a name to pass back, a pointer to the name string (zero terminated) is placed
in the variable pointed to by the <i>mark</i> field. The names are within the	in the variable pointed to by the <i>mark</i> field. The names are within the
compiled pattern; if you wish to retain such a name you must copy it before	compiled pattern; if you wish to retain such a name you must copy it before
freeing the memory of a compiled pattern. If there is no name to pass back, the	freeing the memory of a compiled pattern. If there is no name to pass back, the
variable pointed to by the <i>mark</i> field set to NULL. For details of the	variable pointed to by the <i>mark</i> field is set to NULL. For details of the
backtracking control verbs, see the section entitled	backtracking control verbs, see the section entitled
<a href="pcrepattern#backtrackcontrol">"Backtracking control"</a>	<a href="pcrepattern#backtrackcontrol">"Backtracking control"</a>
in the	in the
Line 1502 Option bits for <b>pcre_exec()</b>	Line 1797 Option bits for <b>pcre_exec()</b>
The unused bits of the <i>options</i> argument for <b>pcre_exec()</b> must be	The unused bits of the <i>options</i> argument for <b>pcre_exec()</b> must be
zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_<i>xxx</i>,	zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_<i>xxx</i>,
PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,	PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,
PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_SOFT, and	PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_HARD, and
PCRE_PARTIAL_HARD.	PCRE_PARTIAL_SOFT.
</P>	</P>
<P>	<P>
If the pattern was successfully studied with the PCRE_STUDY_JIT_COMPILE option,	If the pattern was successfully studied with one of the just-in-time (JIT)
the only supported options for JIT execution are PCRE_NO_UTF8_CHECK,	compile options, the only supported options for JIT execution are
PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, and PCRE_NOTEMPTY_ATSTART. Note in	PCRE_NO_UTF8_CHECK, PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY,
particular that partial matching is not supported. If an unsupported option is	PCRE_NOTEMPTY_ATSTART, PCRE_PARTIAL_HARD, and PCRE_PARTIAL_SOFT. If an
used, JIT execution is disabled and the normal interpretive code in	unsupported option is used, JIT execution is disabled and the normal
<b>pcre_exec()</b> is run.	interpretive code in <b>pcre_exec()</b> is run.
<pre>	<pre>
PCRE_ANCHORED	PCRE_ANCHORED
</pre>	</pre>
Line 1623 unanchored match must start with a specific character,	Line 1918 unanchored match must start with a specific character,
for that character, and fails immediately if it cannot find it, without	for that character, and fails immediately if it cannot find it, without
actually running the main matching function. This means that a special item	actually running the main matching function. This means that a special item
such as (*COMMIT) at the start of a pattern is not considered until after a	such as (*COMMIT) at the start of a pattern is not considered until after a
suitable starting point for the match has been found. When callouts or (*MARK)	suitable starting point for the match has been found. Also, when callouts or
items are in use, these "start-up" optimizations can cause them to be skipped	(*MARK) items are in use, these "start-up" optimizations can cause them to be
if the pattern is never actually used. The start-up optimizations are in effect	skipped if the pattern is never actually used. The start-up optimizations are
a pre-scan of the subject that takes place before the pattern is run.	in effect a pre-scan of the subject that takes place before the pattern is run.
</P>	</P>
<P>	<P>
The PCRE_NO_START_OPTIMIZE option disables the start-up optimizations, possibly	The PCRE_NO_START_OPTIMIZE option disables the start-up optimizations, possibly
Line 1634 causing performance to suffer, but ensuring that in ca	Line 1929 causing performance to suffer, but ensuring that in ca
"no match", the callouts do occur, and that items such as (COMMIT) and (MARK)	"no match", the callouts do occur, and that items such as (COMMIT) and (MARK)
are considered at every possible starting position in the subject string. If	are considered at every possible starting position in the subject string. If
PCRE_NO_START_OPTIMIZE is set at compile time, it cannot be unset at matching	PCRE_NO_START_OPTIMIZE is set at compile time, it cannot be unset at matching
time.	time. The use of PCRE_NO_START_OPTIMIZE at matching time (that is, passing it
	to <b>pcre_exec()</b>) disables JIT execution; in this situation, matching is
	always done using interpretively.
</P>	</P>
<P>	<P>
Setting PCRE_NO_START_OPTIMIZE can change the outcome of a matching operation.	Setting PCRE_NO_START_OPTIMIZE can change the outcome of a matching operation.
Line 1668 returned.	Line 1965 returned.
</pre>	</pre>
When PCRE_UTF8 is set at compile time, the validity of the subject as a UTF-8	When PCRE_UTF8 is set at compile time, the validity of the subject as a UTF-8
string is automatically checked when <b>pcre_exec()</b> is subsequently called.	string is automatically checked when <b>pcre_exec()</b> is subsequently called.
The value of <i>startoffset</i> is also checked to ensure that it points to the	The entire string is checked before any other processing takes place. The value
start of a UTF-8 character. There is a discussion about the validity of UTF-8	of <i>startoffset</i> is also checked to ensure that it points to the start of a
strings in the	UTF-8 character. There is a discussion about the
<a href="pcre.html#utf8strings">section on UTF-8 support</a>	<a href="pcreunicode.html#utf8strings">validity of UTF-8 strings</a>
in the main	in the
<a href="pcre.html"><b>pcre</b></a>	<a href="pcreunicode.html"><b>pcreunicode</b></a>
page. If an invalid UTF-8 sequence of bytes is found, <b>pcre_exec()</b> returns	page. If an invalid sequence of bytes is found, <b>pcre_exec()</b> returns the
the error PCRE_ERROR_BADUTF8 or, if PCRE_PARTIAL_HARD is set and the problem is	error PCRE_ERROR_BADUTF8 or, if PCRE_PARTIAL_HARD is set and the problem is a
a truncated UTF-8 character at the end of the subject, PCRE_ERROR_SHORTUTF8. In	truncated character at the end of the subject, PCRE_ERROR_SHORTUTF8. In both
both cases, information about the precise nature of the error may also be	cases, information about the precise nature of the error may also be returned
returned (see the descriptions of these errors in the section entitled \fIError	(see the descriptions of these errors in the section entitled \fIError return
return values from\fP <b>pcre_exec()</b>	values from\fP <b>pcre_exec()</b>
<a href="#errorlist">below).</a>	<a href="#errorlist">below).</a>
If <i>startoffset</i> contains a value that does not point to the start of a	If <i>startoffset</i> contains a value that does not point to the start of a
UTF-8 character (or to the end of the subject), PCRE_ERROR_BADUTF8_OFFSET is	UTF-8 character (or to the end of the subject), PCRE_ERROR_BADUTF8_OFFSET is
Line 1691 checks for performance reasons, you can set the PCRE_N	Line 1988 checks for performance reasons, you can set the PCRE_N
calling <b>pcre_exec()</b>. You might want to do this for the second and	calling <b>pcre_exec()</b>. You might want to do this for the second and
subsequent calls to <b>pcre_exec()</b> if you are making repeated calls to find	subsequent calls to <b>pcre_exec()</b> if you are making repeated calls to find
all the matches in a single subject string. However, you should be sure that	all the matches in a single subject string. However, you should be sure that
the value of <i>startoffset</i> points to the start of a UTF-8 character (or the	the value of <i>startoffset</i> points to the start of a character (or the end
end of the subject). When PCRE_NO_UTF8_CHECK is set, the effect of passing an	of the subject). When PCRE_NO_UTF8_CHECK is set, the effect of passing an
invalid UTF-8 string as a subject or an invalid value of <i>startoffset</i> is	invalid string as a subject or an invalid value of <i>startoffset</i> is
undefined. Your program may crash.	undefined. Your program may crash or loop.
<pre>	<pre>
PCRE_PARTIAL_HARD	PCRE_PARTIAL_HARD
PCRE_PARTIAL_SOFT	PCRE_PARTIAL_SOFT
Line 1728 The string to be matched by <b>pcre_exec()</b>	Line 2025 The string to be matched by <b>pcre_exec()</b>
</b><br>	</b><br>
<P>	<P>
The subject string is passed to <b>pcre_exec()</b> as a pointer in	The subject string is passed to <b>pcre_exec()</b> as a pointer in
<i>subject</i>, a length (in bytes) in <i>length</i>, and a starting byte offset	<i>subject</i>, a length in <i>length</i>, and a starting offset in
in <i>startoffset</i>. If this is negative or greater than the length of the	<i>startoffset</i>. The units for <i>length</i> and <i>startoffset</i> are bytes
subject, <b>pcre_exec()</b> returns PCRE_ERROR_BADOFFSET. When the starting	for the 8-bit library, 16-bit data items for the 16-bit library, and 32-bit
offset is zero, the search for a match starts at the beginning of the subject,	data items for the 32-bit library.
and this is by far the most common case. In UTF-8 mode, the byte offset must
point to the start of a UTF-8 character (or the end of the subject). Unlike the
pattern string, the subject may contain binary zero bytes.
</P>	</P>
<P>	<P>
	If <i>startoffset</i> is negative or greater than the length of the subject,
	<b>pcre_exec()</b> returns PCRE_ERROR_BADOFFSET. When the starting offset is
	zero, the search for a match starts at the beginning of the subject, and this
	is by far the most common case. In UTF-8 or UTF-16 mode, the offset must point
	to the start of a character, or the end of the subject (in UTF-32 mode, one
	data unit equals one character, so all offsets are valid). Unlike the pattern
	string, the subject may contain binary zeroes.
	</P>
	<P>
A non-zero starting offset is useful when searching for another match in the	A non-zero starting offset is useful when searching for another match in the
same subject by calling <b>pcre_exec()</b> again after a previous success.	same subject by calling <b>pcre_exec()</b> again after a previous success.
Setting <i>startoffset</i> differs from just passing over a shortened string and	Setting <i>startoffset</i> differs from just passing over a shortened string and
Line 1802 rounded down.	Line 2105 rounded down.
When a match is successful, information about captured substrings is returned	When a match is successful, information about captured substrings is returned
in pairs of integers, starting at the beginning of <i>ovector</i>, and	in pairs of integers, starting at the beginning of <i>ovector</i>, and
continuing up to two-thirds of its length at the most. The first element of	continuing up to two-thirds of its length at the most. The first element of
each pair is set to the byte offset of the first character in a substring, and	each pair is set to the offset of the first character in a substring, and the
the second is set to the byte offset of the first character after the end of a	second is set to the offset of the first character after the end of a
substring. <b>Note</b>: these values are always byte offsets, even in UTF-8	substring. These values are always data unit offsets, even in UTF mode. They
mode. They are not character counts.	are byte offsets in the 8-bit library, 16-bit data item offsets in the 16-bit
	library, and 32-bit data item offsets in the 32-bit library. <b>Note</b>: they
	are not character counts.
</P>	</P>
<P>	<P>
The first pair of integers, <i>ovector[0]</i> and <i>ovector[1]</i>, identify the	The first pair of integers, <i>ovector[0]</i> and <i>ovector[1]</i>, identify the
Line 1823 string that it matched that is returned.	Line 2128 string that it matched that is returned.
<P>	<P>
If the vector is too small to hold all the captured substring offsets, it is	If the vector is too small to hold all the captured substring offsets, it is
used as far as possible (up to two-thirds of its length), and the function	used as far as possible (up to two-thirds of its length), and the function
returns a value of zero. If neither the actual string matched not any captured	returns a value of zero. If neither the actual string matched nor any captured
substrings are of interest, <b>pcre_exec()</b> may be called with <i>ovector</i>	substrings are of interest, <b>pcre_exec()</b> may be called with <i>ovector</i>
passed as NULL and <i>ovecsize</i> as zero. However, if the pattern contains	passed as NULL and <i>ovecsize</i> as zero. However, if the pattern contains
back references and the <i>ovector</i> is not big enough to remember the related	back references and the <i>ovector</i> is not big enough to remember the related
Line 2022 time.	Line 2327 time.
<pre>	<pre>
PCRE_ERROR_JIT_STACKLIMIT (-27)	PCRE_ERROR_JIT_STACKLIMIT (-27)
</pre>	</pre>
This error is returned when a pattern that was successfully studied using the	This error is returned when a pattern that was successfully studied using a
PCRE_STUDY_JIT_COMPILE option is being matched, but the memory available for	JIT compile option is being matched, but the memory available for the
the just-in-time processing stack is not large enough. See the	just-in-time processing stack is not large enough. See the
<a href="pcrejit.html"><b>pcrejit</b></a>	<a href="pcrejit.html"><b>pcrejit</b></a>
documentation for more details.	documentation for more details.
	<pre>
	PCRE_ERROR_BADMODE (-28)
	</pre>
	This error is given if a pattern that was compiled by the 8-bit library is
	passed to a 16-bit or 32-bit library function, or vice versa.
	<pre>
	PCRE_ERROR_BADENDIANNESS (-29)
	</pre>
	This error is given if a pattern that was compiled and saved is reloaded on a
	host with different endianness. The utility function
	<b>pcre_pattern_to_host_byte_order()</b> can be used to convert such a pattern
	so that it runs on the new host.
	<pre>
	PCRE_ERROR_JIT_BADOPTION
	</pre>
	This error is returned when a pattern that was successfully studied using a JIT
	compile option is being matched, but the matching mode (partial or complete
	match) does not correspond to any JIT compilation mode. When the JIT fast path
	function is used, this error may be also given for invalid options. See the
	<a href="pcrejit.html"><b>pcrejit</b></a>
	documentation for more details.
	<pre>
	PCRE_ERROR_BADLENGTH (-32)
	</pre>
	This error is given if <b>pcre_exec()</b> is called with a negative value for
	the <i>length</i> argument.
</P>	</P>
<P>	<P>
Error numbers -16 to -20 and -22 are not used by <b>pcre_exec()</b>.	Error numbers -16 to -20, -22, and 30 are not used by <b>pcre_exec()</b>.
<a name="badutf8reasons"></a></P>	<a name="badutf8reasons"></a></P>
<br><b>	<br><b>
Reason codes for invalid UTF-8 strings	Reason codes for invalid UTF-8 strings
</b><br>	</b><br>
<P>	<P>
	This section applies only to the 8-bit library. The corresponding information
	for the 16-bit and 32-bit libraries is given in the
	<a href="pcre16.html"><b>pcre16</b></a>
	and
	<a href="pcre32.html"><b>pcre32</b></a>
	pages.
	</P>
	<P>
When <b>pcre_exec()</b> returns either PCRE_ERROR_BADUTF8 or	When <b>pcre_exec()</b> returns either PCRE_ERROR_BADUTF8 or
PCRE_ERROR_SHORTUTF8, and the size of the output vector (<i>ovecsize</i>) is at	PCRE_ERROR_SHORTUTF8, and the size of the output vector (<i>ovecsize</i>) is at
least 2, the offset of the start of the invalid UTF-8 character is placed in	least 2, the offset of the start of the invalid UTF-8 character is placed in
Line 2103 character.	Line 2442 character.
</pre>	</pre>
The first byte of a character has the value 0xfe or 0xff. These values can	The first byte of a character has the value 0xfe or 0xff. These values can
never occur in a valid UTF-8 string.	never occur in a valid UTF-8 string.
	<pre>
	PCRE_UTF8_ERR22
	</pre>
	This error code was formerly used when the presence of a so-called
	"non-character" caused an error. Unicode corrigendum #9 makes it clear that
	such characters should not cause a string to be rejected, and so this code is
	no longer in use and is never returned.
</P>	</P>
<br><a name="SEC17" href="#TOC1">EXTRACTING CAPTURED SUBSTRINGS BY NUMBER</a><br>	<br><a name="SEC18" href="#TOC1">EXTRACTING CAPTURED SUBSTRINGS BY NUMBER</a><br>
<P>	<P>
<b>int pcre_copy_substring(const char <i>subject</i>, int <i>ovector</i>,</b>	<b>int pcre_copy_substring(const char <i>subject</i>, int <i>ovector</i>,</b>
<b>int <i>stringcount</i>, int <i>stringnumber</i>, char *<i>buffer</i>,</b>	<b> int <i>stringcount</i>, int <i>stringnumber</i>, char *<i>buffer</i>,</b>
<b>int <i>buffersize</i>);</b>	<b> int <i>buffersize</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_get_substring(const char <i>subject</i>, int <i>ovector</i>,</b>	<b>int pcre_get_substring(const char <i>subject</i>, int <i>ovector</i>,</b>
<b>int <i>stringcount</i>, int <i>stringnumber</i>,</b>	<b> int <i>stringcount</i>, int <i>stringnumber</i>,</b>
<b>const char **<i>stringptr</i>);</b>	<b> const char **<i>stringptr</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_get_substring_list(const char *<i>subject</i>,</b>	<b>int pcre_get_substring_list(const char *<i>subject</i>,</b>
<b>int <i>ovector</i>, int <i>stringcount</i>, const char **<i>listptr</i>);</b>	<b> int <i>ovector</i>, int <i>stringcount</i>, const char **<i>listptr</i>);</b>
</P>	</P>
<P>	<P>
Captured substrings can be accessed directly by using the offsets returned by	Captured substrings can be accessed directly by using the offsets returned by
Line 2199 linked via a special interface to another programming	Line 2545 linked via a special interface to another programming
<b>pcre_free</b> directly; it is for these cases that the functions are	<b>pcre_free</b> directly; it is for these cases that the functions are
provided.	provided.
</P>	</P>
<br><a name="SEC18" href="#TOC1">EXTRACTING CAPTURED SUBSTRINGS BY NAME</a><br>	<br><a name="SEC19" href="#TOC1">EXTRACTING CAPTURED SUBSTRINGS BY NAME</a><br>
<P>	<P>
<b>int pcre_get_stringnumber(const pcre *<i>code</i>,</b>	<b>int pcre_get_stringnumber(const pcre *<i>code</i>,</b>
<b>const char *<i>name</i>);</b>	<b> const char *<i>name</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_copy_named_substring(const pcre *<i>code</i>,</b>	<b>int pcre_copy_named_substring(const pcre *<i>code</i>,</b>
<b>const char <i>subject</i>, int <i>ovector</i>,</b>	<b> const char <i>subject</i>, int <i>ovector</i>,</b>
<b>int <i>stringcount</i>, const char *<i>stringname</i>,</b>	<b> int <i>stringcount</i>, const char *<i>stringname</i>,</b>
<b>char *<i>buffer</i>, int <i>buffersize</i>);</b>	<b> char *<i>buffer</i>, int <i>buffersize</i>);</b>
</P>	<br>
<P>	<br>
<b>int pcre_get_named_substring(const pcre *<i>code</i>,</b>	<b>int pcre_get_named_substring(const pcre *<i>code</i>,</b>
<b>const char <i>subject</i>, int <i>ovector</i>,</b>	<b> const char <i>subject</i>, int <i>ovector</i>,</b>
<b>int <i>stringcount</i>, const char *<i>stringname</i>,</b>	<b> int <i>stringcount</i>, const char *<i>stringname</i>,</b>
<b>const char **<i>stringptr</i>);</b>	<b> const char **<i>stringptr</i>);</b>
</P>	</P>
<P>	<P>
To extract a substring by name, you first have to find associated number.	To extract a substring by name, you first have to find associated number.
Line 2263 names are not included in the compiled code. The match	Line 2609 names are not included in the compiled code. The match
numbers. For this reason, the use of different names for subpatterns of the	numbers. For this reason, the use of different names for subpatterns of the
same number causes an error at compile time.	same number causes an error at compile time.
</P>	</P>
<br><a name="SEC19" href="#TOC1">DUPLICATE SUBPATTERN NAMES</a><br>	<br><a name="SEC20" href="#TOC1">DUPLICATE SUBPATTERN NAMES</a><br>
<P>	<P>
<b>int pcre_get_stringtable_entries(const pcre *<i>code</i>,</b>	<b>int pcre_get_stringtable_entries(const pcre *<i>code</i>,</b>
<b>const char <i>name</i>, char <i>first</i>, char *<i>last</i>);</b>	<b> const char <i>name</i>, char <i>first</i>, char *<i>last</i>);</b>
</P>	</P>
<P>	<P>
When a pattern is compiled with the PCRE_DUPNAMES option, names for subpatterns	When a pattern is compiled with the PCRE_DUPNAMES option, names for subpatterns
Line 2301 described above in the section entitled <i>Information	Line 2647 described above in the section entitled <i>Information
Given all the relevant entries for the name, you can extract each of their	Given all the relevant entries for the name, you can extract each of their
numbers, and hence the captured data, if any.	numbers, and hence the captured data, if any.
</P>	</P>
<br><a name="SEC20" href="#TOC1">FINDING ALL POSSIBLE MATCHES</a><br>	<br><a name="SEC21" href="#TOC1">FINDING ALL POSSIBLE MATCHES</a><br>
<P>	<P>
The traditional matching function uses a similar algorithm to Perl, which stops	The traditional matching function uses a similar algorithm to Perl, which stops
when it finds the first match, starting at a given point in the subject. If you	when it finds the first match, starting at a given point in the subject. If you
Line 2319 When your callout function is called, extract and save	Line 2665 When your callout function is called, extract and save
substring. Then return 1, which forces <b>pcre_exec()</b> to backtrack and try	substring. Then return 1, which forces <b>pcre_exec()</b> to backtrack and try
other alternatives. Ultimately, when it runs out of matches, <b>pcre_exec()</b>	other alternatives. Ultimately, when it runs out of matches, <b>pcre_exec()</b>
will yield PCRE_ERROR_NOMATCH.	will yield PCRE_ERROR_NOMATCH.
	</P>
	<br><a name="SEC22" href="#TOC1">OBTAINING AN ESTIMATE OF STACK USAGE</a><br>
	<P>
	Matching certain patterns using <b>pcre_exec()</b> can use a lot of process
	stack, which in certain environments can be rather limited in size. Some users
	find it helpful to have an estimate of the amount of stack that is used by
	<b>pcre_exec()</b>, to help them set recursion limits, as described in the
	<a href="pcrestack.html"><b>pcrestack</b></a>
	documentation. The estimate that is output by <b>pcretest</b> when called with
	the <b>-m</b> and <b>-C</b> options is obtained by calling <b>pcre_exec</b> with
	the values NULL, NULL, NULL, -999, and -999 for its first five arguments.
	</P>
	<P>
	Normally, if its first argument is NULL, <b>pcre_exec()</b> immediately returns
	the negative error code PCRE_ERROR_NULL, but with this special combination of
	arguments, it returns instead a negative number whose absolute value is the
	approximate stack frame size in bytes. (A negative number is used so that it is
	clear that no match has happened.) The value is approximate because in some
	cases, recursive calls to <b>pcre_exec()</b> occur when there are one or two
	additional variables on the stack.
	</P>
	<P>
	If PCRE has been compiled to use the heap instead of the stack for recursion,
	the value returned is the size of each block that is obtained from the heap.
<a name="dfamatch"></a></P>	<a name="dfamatch"></a></P>
<br><a name="SEC21" href="#TOC1">MATCHING A PATTERN: THE ALTERNATIVE FUNCTION</a><br>	<br><a name="SEC23" href="#TOC1">MATCHING A PATTERN: THE ALTERNATIVE FUNCTION</a><br>
<P>	<P>
<b>int pcre_dfa_exec(const pcre <i>code</i>, const pcre_extra <i>extra</i>,</b>	<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> 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>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
<b>int *<i>workspace</i>, int <i>wscount</i>);</b>	<b> int *<i>workspace</i>, int <i>wscount</i>);</b>
</P>	</P>
<P>	<P>
The function <b>pcre_dfa_exec()</b> is called to match a subject string against	The function <b>pcre_dfa_exec()</b> is called to match a subject string against
Line 2454 matching string is given first. If there were too many	Line 2824 matching string is given first. If there were too many
the longest matches. Unlike <b>pcre_exec()</b>, <b>pcre_dfa_exec()</b> can use	the longest matches. Unlike <b>pcre_exec()</b>, <b>pcre_dfa_exec()</b> can use
the entire <i>ovector</i> for returning matched strings.	the entire <i>ovector</i> for returning matched strings.
</P>	</P>
	<P>
	NOTE: PCRE's "auto-possessification" optimization usually applies to character
	repeats at the end of a pattern (as well as internally). For example, the
	pattern "a\d+" is compiled as if it were "a\d++" because there is no point
	even considering the possibility of backtracking into the repeated digits. For
	DFA matching, this means that only one possible match is found. If you really
	do want multiple matches in such cases, either use an ungreedy repeat
	("a\d+?") or set the PCRE_NO_AUTO_POSSESS option when compiling.
	</P>
<br><b>	<br><b>
Error returns from <b>pcre_dfa_exec()</b>	Error returns from <b>pcre_dfa_exec()</b>
</b><br>	</b><br>
Line 2494 When a recursive subpattern is processed, the matching	Line 2873 When a recursive subpattern is processed, the matching
recursively, using private vectors for <i>ovector</i> and <i>workspace</i>. This	recursively, using private vectors for <i>ovector</i> and <i>workspace</i>. This
error is given if the output vector is not large enough. This should be	error is given if the output vector is not large enough. This should be
extremely rare, as a vector of size 1000 is used.	extremely rare, as a vector of size 1000 is used.
	<pre>
	PCRE_ERROR_DFA_BADRESTART (-30)
	</pre>
	When <b>pcre_dfa_exec()</b> is called with the <b>PCRE_DFA_RESTART</b> option,
	some plausibility checks are made on the contents of the workspace, which
	should contain data about the previous partial match. If any of these checks
	fail, this error is given.
</P>	</P>
<br><a name="SEC22" href="#TOC1">SEE ALSO</a><br>	<br><a name="SEC24" href="#TOC1">SEE ALSO</a><br>
<P>	<P>
<b>pcrebuild</b>(3), <b>pcrecallout</b>(3), <b>pcrecpp(3)</b>(3),	<b>pcre16</b>(3), <b>pcre32</b>(3), <b>pcrebuild</b>(3), <b>pcrecallout</b>(3),
<b>pcrematching</b>(3), <b>pcrepartial</b>(3), <b>pcreposix</b>(3),	<b>pcrecpp(3)</b>(3), <b>pcrematching</b>(3), <b>pcrepartial</b>(3),
<b>pcreprecompile</b>(3), <b>pcresample</b>(3), <b>pcrestack</b>(3).	<b>pcreposix</b>(3), <b>pcreprecompile</b>(3), <b>pcresample</b>(3),
	<b>pcrestack</b>(3).
</P>	</P>
<br><a name="SEC23" href="#TOC1">AUTHOR</a><br>	<br><a name="SEC25" href="#TOC1">AUTHOR</a><br>
<P>	<P>
Philip Hazel	Philip Hazel
<br>	<br>
Line 2510 University Computing Service	Line 2897 University Computing Service
Cambridge CB2 3QH, England.	Cambridge CB2 3QH, England.
<br>	<br>
</P>	</P>
<br><a name="SEC24" href="#TOC1">REVISION</a><br>	<br><a name="SEC26" href="#TOC1">REVISION</a><br>
<P>	<P>
Last updated: 02 December 2011	Last updated: 12 November 2013
<br>	<br>
Copyright © 1997-2011 University of Cambridge.	Copyright © 1997-2013 University of Cambridge.
<br>	<br>
<p>	<p>
Return to the <a href="index.html">PCRE index page</a>.	Return to the <a href="index.html">PCRE index page</a>.

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