Revision: 157
http://www.exim.org/viewvc/pcre2?view=rev&revision=157
Author: ph10
Date: 2014-11-21 16:45:06 +0000 (Fri, 21 Nov 2014)
Log Message:
-----------
More documentation and file tidies.
Modified Paths:
--------------
code/trunk/CMakeLists.txt
code/trunk/RunTest
code/trunk/doc/html/pcre2.html
code/trunk/doc/html/pcre2api.html
code/trunk/doc/html/pcre2build.html
code/trunk/doc/html/pcre2callout.html
code/trunk/doc/html/pcre2compat.html
code/trunk/doc/html/pcre2grep.html
code/trunk/doc/html/pcre2jit.html
code/trunk/doc/html/pcre2limits.html
code/trunk/doc/html/pcre2matching.html
code/trunk/doc/html/pcre2partial.html
code/trunk/doc/html/pcre2pattern.html
code/trunk/doc/html/pcre2perform.html
code/trunk/doc/html/pcre2posix.html
code/trunk/doc/html/pcre2sample.html
code/trunk/doc/html/pcre2stack.html
code/trunk/doc/html/pcre2syntax.html
code/trunk/doc/html/pcre2test.html
code/trunk/doc/html/pcre2unicode.html
code/trunk/doc/pcre2.3
code/trunk/doc/pcre2.txt
code/trunk/doc/pcre2api.3
code/trunk/src/pcre2_jit_compile.c
code/trunk/src/pcre2_match.c
Modified: code/trunk/CMakeLists.txt
===================================================================
--- code/trunk/CMakeLists.txt 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/CMakeLists.txt 2014-11-21 16:45:06 UTC (rev 157)
@@ -394,7 +394,7 @@
src/pcre2_pattern_info.c
src/pcre2_string_utils.c
src/pcre2_study.c
- src/pcre2_substitute.c
+ src/pcre2_substitute.c
src/pcre2_substring.c
src/pcre2_tables.c
src/pcre2_ucd.c
Modified: code/trunk/RunTest
===================================================================
--- code/trunk/RunTest 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/RunTest 2014-11-21 16:45:06 UTC (rev 157)
@@ -286,7 +286,7 @@
test2stack="-S 16"
else
test2stack=""
-fi
+fi
# All of 8-bit, 16-bit, and 32-bit character strings may be supported, but only
# one need be.
Modified: code/trunk/doc/html/pcre2.html
===================================================================
--- code/trunk/doc/html/pcre2.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -25,9 +25,10 @@
of functions, written in C, that implement regular expression pattern matching
using the same syntax and semantics as Perl, with just a few differences. Some
features that appeared in Python and the original PCRE before they appeared in
-Perl are also available using the Python syntax, there is some support for one
-or two .NET and Oniguruma syntax items, and there are options for requesting
-some minor changes that give better ECMAScript (aka JavaScript) compatibility.
+Perl are also available using the Python syntax. There is also some support for
+one or two .NET and Oniguruma syntax items, and there are options for
+requesting some minor changes that give better ECMAScript (aka JavaScript)
+compatibility.
</P>
<P>
The source code for PCRE2 can be compiled to support 8-bit, 16-bit, or 32-bit
@@ -36,7 +37,7 @@
Zoltan Herczeg and Christian Persch, respectively. In all three cases, strings
can be interpreted either as one character per code unit, or as UTF-encoded
Unicode, with support for Unicode general category properties. Unicode support
-is optional at build time (but is the default); however, processing strings as
+is optional at build time (but is the default). However, processing strings as
UTF code units must be enabled explicitly at run time. The version of Unicode
in use can be discovered by running
<pre>
@@ -143,17 +144,17 @@
pcre2compat discussion of Perl compatibility
pcre2demo a demonstration C program that uses PCRE2
pcre2grep description of the <b>pcre2grep</b> command (8-bit only)
- pcre2jit discussion of the just-in-time optimization support
+ pcre2jit discussion of just-in-time optimization support
pcre2limits details of size and other limits
pcre2matching discussion of the two matching algorithms
pcre2partial details of the partial matching facility
- pcre2pattern syntax and semantics of supported regular expressions
+ pcre2pattern syntax and semantics of supported regular expression patterns
pcre2perform discussion of performance issues
pcre2posix the POSIX-compatible C API for the 8-bit library
pcre2sample discussion of the pcre2demo program
pcre2stack discussion of stack usage
pcre2syntax quick syntax reference
- pcre2test description of the <b>pcre2test</b> testing command
+ pcre2test description of the <b>pcre2test</b> command
pcre2unicode discussion of Unicode and UTF support
</pre>
In the "man" and HTML formats, there is also a short page for each C library
@@ -165,7 +166,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<P>
@@ -174,7 +175,7 @@
</P>
<br><a name="SEC5" href="#TOC1">REVISION</a><br>
<P>
-Last updated: 03 November 2014
+Last updated: 18 November 2014
<br>
Copyright © 1997-2014 University of Cambridge.
<br>
Modified: code/trunk/doc/html/pcre2api.html
===================================================================
--- code/trunk/doc/html/pcre2api.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2api.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -37,16 +37,18 @@
<li><a name="TOC22" href="#SEC22">MATCHING A PATTERN: THE TRADITIONAL FUNCTION</a>
<li><a name="TOC23" href="#SEC23">NEWLINE HANDLING WHEN MATCHING</a>
<li><a name="TOC24" href="#SEC24">HOW PCRE2_MATCH() RETURNS A STRING AND CAPTURED SUBSTRINGS</a>
-<li><a name="TOC25" href="#SEC25">EXTRACTING CAPTURED SUBSTRINGS BY NUMBER</a>
-<li><a name="TOC26" href="#SEC26">EXTRACTING A LIST OF ALL CAPTURED SUBSTRINGS</a>
-<li><a name="TOC27" href="#SEC27">EXTRACTING CAPTURED SUBSTRINGS BY NAME</a>
-<li><a name="TOC28" href="#SEC28">CREATING A NEW STRING WITH SUBSTITUTIONS</a>
-<li><a name="TOC29" href="#SEC29">DUPLICATE SUBPATTERN NAMES</a>
-<li><a name="TOC30" href="#SEC30">FINDING ALL POSSIBLE MATCHES</a>
-<li><a name="TOC31" href="#SEC31">MATCHING A PATTERN: THE ALTERNATIVE FUNCTION</a>
-<li><a name="TOC32" href="#SEC32">SEE ALSO</a>
-<li><a name="TOC33" href="#SEC33">AUTHOR</a>
-<li><a name="TOC34" href="#SEC34">REVISION</a>
+<li><a name="TOC25" href="#SEC25">OTHER INFORMATION ABOUT A MATCH</a>
+<li><a name="TOC26" href="#SEC26">ERROR RETURNS FROM <b>pcre2_match()</b></a>
+<li><a name="TOC27" href="#SEC27">EXTRACTING CAPTURED SUBSTRINGS BY NUMBER</a>
+<li><a name="TOC28" href="#SEC28">EXTRACTING A LIST OF ALL CAPTURED SUBSTRINGS</a>
+<li><a name="TOC29" href="#SEC29">EXTRACTING CAPTURED SUBSTRINGS BY NAME</a>
+<li><a name="TOC30" href="#SEC30">CREATING A NEW STRING WITH SUBSTITUTIONS</a>
+<li><a name="TOC31" href="#SEC31">DUPLICATE SUBPATTERN NAMES</a>
+<li><a name="TOC32" href="#SEC32">FINDING ALL POSSIBLE MATCHES AT ONE POSITION</a>
+<li><a name="TOC33" href="#SEC33">MATCHING A PATTERN: THE ALTERNATIVE FUNCTION</a>
+<li><a name="TOC34" href="#SEC34">SEE ALSO</a>
+<li><a name="TOC35" href="#SEC35">AUTHOR</a>
+<li><a name="TOC36" href="#SEC36">REVISION</a>
</ul>
<P>
<b>#include <pcre2.h></b>
@@ -436,13 +438,9 @@
<P>
Each of the first three conventions is used by at least one operating system as
its standard newline sequence. When PCRE2 is built, a default can be specified.
-The default default is LF, which is the Unix standard. When PCRE2 is run, the
-default can be overridden, either when a pattern is compiled, or when it is
-matched.
-</P>
-<P>
-The newline convention can be changed when calling <b>pcre2_compile()</b>, or it
-can be specified by special text at the start of the pattern itself; this
+The default default is LF, which is the Unix standard. However, the newline
+convention can be changed by an application when calling <b>pcre2_compile()</b>,
+or it can be specified by special text at the start of the pattern itself; this
overrides any other settings. See the
<a href="pcre2pattern.html"><b>pcre2pattern</b></a>
page for details of the special character sequences.
@@ -459,8 +457,8 @@
</P>
<P>
The choice of newline convention does not affect the interpretation of
-the \n or \r escape sequences, nor does it affect what \R matches, which has
-its own separate control.
+the \n or \r escape sequences, nor does it affect what \R matches; this has
+its own separate convention.
</P>
<br><a name="SEC13" href="#TOC1">MULTITHREADING</a><br>
<P>
@@ -472,7 +470,7 @@
</P>
<P>
There are several different blocks of data that are used to pass information
-between the application and the PCRE libraries.
+between the application and the PCRE2 libraries.
</P>
<P>
(1) A pointer to the compiled form of a pattern is returned to the user when
@@ -572,11 +570,11 @@
A compile context is required if you want to change the default values of any
of the following compile-time parameters:
<pre>
- What \R matches (Unicode newlines or CR, LF, CRLF only);
- PCRE2's character tables;
- The newline character sequence;
- The compile time nested parentheses limit;
- An external function for stack checking.
+ What \R matches (Unicode newlines or CR, LF, CRLF only)
+ PCRE2's character tables
+ The newline character sequence
+ The compile time nested parentheses limit
+ An external function for stack checking
</pre>
A compile context is also required if you are using custom memory management.
If none of these apply, just pass NULL as the context argument of
@@ -604,9 +602,8 @@
<br>
The value must be PCRE2_BSR_ANYCRLF, to specify that \R matches only CR, LF,
or CRLF, or PCRE2_BSR_UNICODE, to specify that \R matches any Unicode line
-ending sequence. The value of this parameter does not affect what is compiled;
-it is just saved with the compiled pattern. The value is used by the JIT
-compiler and by the two interpreted matching functions, <i>pcre2_match()</i> and
+ending sequence. The value is used by the JIT compiler and by the two
+interpreted matching functions, <i>pcre2_match()</i> and
<i>pcre2_dfa_match()</i>.
<b>int pcre2_set_character_tables(pcre2_compile_context *<i>ccontext</i>,</b>
<b> const unsigned char *<i>tables</i>);</b>
@@ -709,12 +706,12 @@
which ignores it.
</P>
<P>
-When <b>pcre2_match()</b> is called with a pattern that was successfully studied
-with <b>pcre2_jit_compile()</b>, the way that the matching is executed is
-entirely different. However, there is still the possibility of runaway matching
-that goes on for a very long time, and so the <i>match_limit</i> value is also
-used in this case (but in a different way) to limit how long the matching can
-continue.
+When <b>pcre2_match()</b> is called with a pattern that was successfully
+processed by <b>pcre2_jit_compile()</b>, the way in which matching is executed
+is entirely different. However, there is still the possibility of runaway
+matching that goes on for a very long time, and so the <i>match_limit</i> value
+is also used in this case (but in a different way) to limit how long the
+matching can continue.
</P>
<P>
The default value for the limit can be set when PCRE2 is built; the default
@@ -770,15 +767,17 @@
<a href="pcre2stack.html"><b>pcre2stack</b></a>
documentation. See the
<a href="pcre2build.html"><b>pcre2build</b></a>
-documentation for details of how to build PCRE2. Using the heap for recursion
-is a non-standard way of building PCRE2, for use in environments that have
-limited stacks. Because of the greater use of memory management,
-<b>pcre2_match()</b> runs more slowly. Functions that are different to the
-general custom memory functions are provided so that special-purpose external
-code can be used for this case, because the memory blocks are all the same
-size. The blocks are retained by <b>pcre2_match()</b> until it is about to exit
-so that they can be re-used when possible during the match. In the absence of
-these functions, the normal custom memory management functions are used, if
+documentation for details of how to build PCRE2.
+</P>
+<P>
+Using the heap for recursion is a non-standard way of building PCRE2, for use
+in environments that have limited stacks. Because of the greater use of memory
+management, <b>pcre2_match()</b> runs more slowly. Functions that are different
+to the general custom memory functions are provided so that special-purpose
+external code can be used for this case, because the memory blocks are all the
+same size. The blocks are retained by <b>pcre2_match()</b> until it is about to
+exit so that they can be re-used when possible during the match. In the absence
+of these functions, the normal custom memory management functions are used, if
supplied, otherwise the system functions.
</P>
<br><a name="SEC15" href="#TOC1">CHECKING BUILD-TIME OPTIONS</a><br>
@@ -809,9 +808,10 @@
PCRE2_CONFIG_BSR
</pre>
The output is an integer whose value indicates what character sequences the \R
-escape sequence matches by default. A value of 0 means that \R matches any
-Unicode line ending sequence; a value of 1 means that \R matches only CR, LF,
-or CRLF. The default can be overridden when a pattern is compiled or matched.
+escape sequence matches by default. A value of PCRE2_BSR_UNICODE means that \R
+matches any Unicode line ending sequence; a value of PCRE2_BSR_ANYCRLF means
+that \R matches only CR, LF, or CRLF. The default can be overridden when a
+pattern is compiled.
<pre>
PCRE2_CONFIG_JIT
</pre>
@@ -821,7 +821,7 @@
PCRE2_CONFIG_JITTARGET
</pre>
The <i>where</i> argument should point to a buffer that is at least 48 code
-units long. (The exact length needed can be found by calling
+units long. (The exact length required can be found by calling
<b>pcre2_config()</b> with <b>where</b> set to NULL.) The buffer is filled with a
string that contains the name of the architecture for which the JIT compiler is
configured, for example "x86 32bit (little endian + unaligned)". If JIT support
@@ -855,11 +855,11 @@
The output is an integer whose value specifies the default character sequence
that is recognized as meaning "newline". The values are:
<pre>
- 1 Carriage return (CR)
- 2 Linefeed (LF)
- 3 Carriage return, linefeed (CRLF)
- 4 Any Unicode line ending
- 5 Any of CR, LF, or CRLF
+ PCRE2_NEWLINE_CR Carriage return (CR)
+ PCRE2_NEWLINE_LF Linefeed (LF)
+ PCRE2_NEWLINE_CRLF Carriage return, linefeed (CRLF)
+ PCRE2_NEWLINE_ANY Any Unicode line ending
+ PCRE2_NEWLINE_ANYCRLF Any of CR, LF, or CRLF
</pre>
The default should normally correspond to the standard sequence for your
operating system.
@@ -891,7 +891,7 @@
PCRE2_CONFIG_UNICODE_VERSION
</pre>
The <i>where</i> argument should point to a buffer that is at least 24 code
-units long. (The exact length needed can be found by calling
+units long. (The exact length required can be found by calling
<b>pcre2_config()</b> with <b>where</b> set to NULL.) If PCRE2 has been compiled
without Unicode support, the buffer is filled with the text "Unicode not
supported". Otherwise, the Unicode version string (for example, "7.0.0") is
@@ -906,7 +906,7 @@
PCRE2_CONFIG_VERSION
</pre>
The <i>where</i> argument should point to a buffer that is at least 12 code
-units long. (The exact length needed can be found by calling
+units long. (The exact length required can be found by calling
<b>pcre2_config()</b> with <b>where</b> set to NULL.) The buffer is filled with
the PCRE2 version string, zero-terminated. The number of code units used is
returned. This is the length of the string plus one unit for the terminating
@@ -922,17 +922,17 @@
<b>pcre2_code_free(pcre2_code *<i>code</i>);</b>
</P>
<P>
-This function compiles a pattern, defined by a pointer to a string of code
-units and a length, into an internal form. If the pattern is zero-terminated,
-the length should be specified as PCRE2_ZERO_TERMINATED. The function returns a
-pointer to a block of memory that contains the compiled pattern and related
-data. The caller must free the memory by calling <b>pcre2_code_free()</b> when
-it is no longer needed.
+The <b>pcre2_compile()</b> function compiles a pattern into an internal form.
+The pattern is defined by a pointer to a string of code units and a length, If
+the pattern is zero-terminated, the length can be specified as
+PCRE2_ZERO_TERMINATED. The function returns a pointer to a block of memory that
+contains the compiled pattern and related data. The caller must free the memory
+by calling <b>pcre2_code_free()</b> when it is no longer needed.
</P>
<P>
-If the compile context argument <i>ccontext</i> is NULL, the memory is obtained
-by calling <b>malloc()</b>. Otherwise, it is obtained from the same memory
-function that was used for the compile context.
+If the compile context argument <i>ccontext</i> is NULL, memory for the compiled
+pattern is obtained by calling <b>malloc()</b>. Otherwise, it is obtained from
+the same memory function that was used for the compile context.
</P>
<P>
The <i>options</i> argument contains various bit settings that affect the
@@ -1247,7 +1247,7 @@
in the
<a href="pcre2pattern.html"><b>pcre2pattern</b></a>
page. If you set PCRE2_UCP, matching one of the items it affects takes much
-longer. The option is available only if PCRE2 has been compiled with UTF
+longer. The option is available only if PCRE2 has been compiled with Unicode
support.
<pre>
PCRE2_UNGREEDY
@@ -1260,9 +1260,10 @@
</pre>
This option causes PCRE2 to regard both the pattern and the subject strings
that are subsequently processed as strings of UTF characters instead of
-single-code-unit strings. However, it is available only when PCRE2 is built to
-include UTF support. If not, the use of this option provokes an error. Details
-of how this option changes the behaviour of PCRE2 are given in the
+single-code-unit strings. It is available when PCRE2 is built to include
+Unicode support (which is the default). If Unicode support is not available,
+the use of this option provokes an error. Details of how this option changes
+the behaviour of PCRE2 are given in the
<a href="pcre2unicode.html"><b>pcre2unicode</b></a>
page.
</P>
@@ -1318,13 +1319,12 @@
<P>
PCRE2 handles caseless matching, and determines whether characters are letters,
digits, or whatever, by reference to a set of tables, indexed by character code
-point. When running in UTF-8 mode, or using the 16-bit or 32-bit libraries,
-this applies only to characters with code points less than 256. By default,
-higher-valued code points never match escapes such as \w or \d. However, if
-PCRE2 is built with UTF support, all characters can be tested with \p and \P,
-or, alternatively, the PCRE2_UCP option can be set when a pattern is compiled;
-this causes \w and friends to use Unicode property support instead of the
-built-in tables.
+point. This applies only to characters whose code points are less than 256. By
+default, higher-valued code points never match escapes such as \w or \d.
+However, if PCRE2 is built with UTF support, all characters can be tested with
+\p and \P, or, alternatively, the PCRE2_UCP option can be set when a pattern
+is compiled; this causes \w and friends to use Unicode property support
+instead of the built-in tables.
</P>
<P>
The use of locales with Unicode is discouraged. If you are handling characters
@@ -1437,9 +1437,9 @@
PCRE2_INFO_BSR
</pre>
The output is a uint32_t whose value indicates what character sequences the \R
-escape sequence matches by default. A value of 0 means that \R matches any
-Unicode line ending sequence; a value of 1 means that \R matches only CR, LF,
-or CRLF. The default can be overridden when a pattern is matched.
+escape sequence matches. A value of PCRE2_BSR_UNICODE means that \R matches
+any Unicode line ending sequence; a value of PCRE2_BSR_ANYCRLF means that \R
+matches only CR, LF, or CRLF.
<pre>
PCRE2_INFO_CAPTURECOUNT
</pre>
@@ -1581,17 +1581,20 @@
<P>
The map consists of a number of fixed-size entries. PCRE2_INFO_NAMECOUNT gives
the number of entries, and PCRE2_INFO_NAMEENTRYSIZE gives the size of each
-entry; both of these return a <b>uint32_t</b> value. The entry size depends on
-the length of the longest name. PCRE2_INFO_NAMETABLE returns a pointer to the
-first entry of the table. This is a PCRE2_SPTR pointer to a block of code
-units. In the 8-bit library, the first two bytes of each entry are the number
-of the capturing parenthesis, 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.
+entry in code units; both of these return a <b>uint32_t</b> value. The entry
+size depends on the length of the longest name.
</P>
<P>
+PCRE2_INFO_NAMETABLE returns a pointer to the first entry of the table. This is
+a PCRE2_SPTR pointer to a block of code units. In the 8-bit library, the first
+two bytes of each entry are the number of the capturing parenthesis, most
+significant byte first. In the 16-bit library, the pointer points to 16-bit
+code units, the first of which contains the parenthesis number. In the 32-bit
+library, the pointer points to 32-bit code units, the first of which contains
+the parenthesis number. The rest of the entry is the corresponding name, zero
+terminated.
+</P>
+<P>
The names are in alphabetical order. If (?| is used to create multiple groups
with the same number, as described in the
<a href="pcre2pattern.html#dupsubpatternnumber">section on duplicate subpattern numbers</a>
@@ -1629,17 +1632,16 @@
<pre>
PCRE2_INFO_NEWLINE
</pre>
-The output is a <b>uint32_t</b> whose value specifies the default character
-sequence that will be recognized as meaning "newline" while matching. The
-values are:
+The output is a <b>uint32_t</b> with one of the following values:
<pre>
- 1 Carriage return (CR)
- 2 Linefeed (LF)
- 3 Carriage return, linefeed (CRLF)
- 4 Any Unicode line ending
- 5 Any of CR, LF, or CRLF
+ PCRE2_NEWLINE_CR Carriage return (CR)
+ PCRE2_NEWLINE_LF Linefeed (LF)
+ PCRE2_NEWLINE_CRLF Carriage return, linefeed (CRLF)
+ PCRE2_NEWLINE_ANY Any Unicode line ending
+ PCRE2_NEWLINE_ANYCRLF Any of CR, LF, or CRLF
</pre>
-The default can be overridden when a pattern is matched.
+This specifies the default character sequence that will be recognized as
+meaning "newline" while matching.
<pre>
PCRE2_INFO_RECURSIONLIMIT
</pre>
@@ -1675,18 +1677,19 @@
data block, which is an opaque structure that is accessed by function calls. In
particular, the match data block contains a vector of offsets into the subject
string that define the matched part of the subject and any substrings that were
-capured. This is know as the <i>ovector</i>.
+captured. This is know as the <i>ovector</i>.
</P>
<P>
-Before calling <b>pcre2_match()</b> or <b>pcre2_dfa_match()</b> you must create a
-match data block by calling one of the creation functions above. For
-<b>pcre2_match_data_create()</b>, the first argument is the number of pairs of
-offsets in the <i>ovector</i>. One pair of offsets is required to identify the
-string that matched the whole pattern, with another pair for each captured
-substring. For example, a value of 4 creates enough space to record the matched
-portion of the subject plus three captured substrings. A minimum of at least 1
-pair is imposed by <b>pcre2_match_data_create()</b>, so it is always possible to
-return the overall matched string.
+Before calling <b>pcre2_match()</b>, <b>pcre2_dfa_match()</b>, or
+<b>pcre2_jit_match()</b> you must create a match data block by calling one of
+the creation functions above. For <b>pcre2_match_data_create()</b>, the first
+argument is the number of pairs of offsets in the <i>ovector</i>. One pair of
+offsets is required to identify the string that matched the whole pattern, with
+another pair for each captured substring. For example, a value of 4 creates
+enough space to record the matched portion of the subject plus three captured
+substrings. A minimum of at least 1 pair is imposed by
+<b>pcre2_match_data_create()</b>, so it is always possible to return the overall
+matched string.
</P>
<P>
For <b>pcre2_match_data_create_from_pattern()</b>, the first argument is a
@@ -1694,15 +1697,16 @@
exactly the right size to hold all the substrings a pattern might capture.
</P>
<P>
-The second argument of both these functions ia a pointer to a general context,
+The second argument of both these functions is a pointer to a general context,
which can specify custom memory management for obtaining the memory for the
match data block. If you are not using custom memory management, pass NULL.
</P>
<P>
A match data block can be used many times, with the same or different compiled
patterns. When it is no longer needed, it should be freed by calling
-<b>pcre2_match_data_free()</b>. How to extract information from a match data
-block after a match operation is described in the sections on
+<b>pcre2_match_data_free()</b>. You can extract information from a match data
+block after a match operation has finished, using functions that are described
+in the sections on
<a href="#matchedstrings">matched strings</a>
and
<a href="#matchotherdata">other match data</a>
@@ -1816,12 +1820,10 @@
PCRE2_PARTIAL_HARD, and PCRE2_PARTIAL_SOFT. Their action is described below.
</P>
<P>
-If the pattern was successfully processed by the just-in-time (JIT) compiler,
-the only supported options for matching using the JIT code are PCRE2_NOTBOL,
-PCRE2_NOTEOL, PCRE2_NOTEMPTY, PCRE2_NOTEMPTY_ATSTART, PCRE2_NO_UTF_CHECK,
-PCRE2_PARTIAL_HARD, and PCRE2_PARTIAL_SOFT. If an unsupported option is used,
-JIT matching is disabled and the normal interpretive code in
-<b>pcre2_match()</b> is run.
+Setting PCRE2_ANCHORED at match time is not supported by the just-in-time (JIT)
+compiler. If it is set, JIT matching is disabled and the normal interpretive
+code in <b>pcre2_match()</b> is run. The remaining options are supported for JIT
+matching.
<pre>
PCRE2_ANCHORED
</pre>
@@ -1835,17 +1837,18 @@
</pre>
This option specifies that first character of the subject string is not the
beginning of a line, so the circumflex metacharacter should not match before
-it. Setting this without PCRE2_MULTILINE (at compile time) causes circumflex
-never to match. This option affects only the behaviour of the circumflex
-metacharacter. It does not affect \A.
+it. Setting this without having set PCRE2_MULTILINE at compile time causes
+circumflex never to match. This option affects only the behaviour of the
+circumflex metacharacter. It does not affect \A.
<pre>
PCRE2_NOTEOL
</pre>
This option specifies that the end of the subject string is not the end of a
line, so the dollar metacharacter should not match it nor (except in multiline
-mode) a newline immediately before it. Setting this without PCRE2_MULTILINE (at
-compile time) causes dollar never to match. This option affects only the
-behaviour of the dollar metacharacter. It does not affect \Z or \z.
+mode) a newline immediately before it. Setting this without having set
+PCRE2_MULTILINE at compile time causes dollar never to match. This option
+affects only the behaviour of the dollar metacharacter. It does not affect \Z
+or \z.
<pre>
PCRE2_NOTEMPTY
</pre>
@@ -1857,13 +1860,16 @@
</pre>
is applied to a string not beginning with "a" or "b", it matches an empty
string at the start of the subject. With PCRE2_NOTEMPTY set, this match is not
-valid, so PCRE2 searches further into the string for occurrences of "a" or "b".
+valid, so <b>pcre2_match()</b> searches further into the string for occurrences
+of "a" or "b".
<pre>
PCRE2_NOTEMPTY_ATSTART
</pre>
-This is like PCRE2_NOTEMPTY, except that an empty string match that is not at
-the start of the subject is permitted. If the pattern is anchored, such a match
-can occur only if the pattern contains \K.
+This is like PCRE2_NOTEMPTY, except that it locks out an empty string match
+only at the first matching position, that is, at the start of the subject plus
+the starting offset. An empty string match later in the subject is permitted.
+If the pattern is anchored, such a match can occur only if the pattern contains
+\K.
<pre>
PCRE2_NO_UTF_CHECK
</pre>
@@ -1904,8 +1910,8 @@
PCRE2_PARTIAL_SOFT (but not PCRE2_PARTIAL_HARD) is set, matching continues by
testing any remaining alternatives. Only if no complete match can be found is
PCRE2_ERROR_PARTIAL returned instead of PCRE2_ERROR_NOMATCH. In other words,
-PCRE2_PARTIAL_SOFT says that the caller is prepared to handle a partial match,
-but only if no complete match can be found.
+PCRE2_PARTIAL_SOFT specifies that the caller is prepared to handle a partial
+match, but only if no complete match can be found.
</P>
<P>
If PCRE2_PARTIAL_HARD is set, it overrides PCRE2_PARTIAL_SOFT. In this case, if
@@ -1928,14 +1934,14 @@
<a href="#compilecontext">compile context.</a>
During matching, the newline choice affects the behaviour of the dot,
circumflex, and dollar metacharacters. It may also alter the way the match
-position is advanced after a match failure for an unanchored pattern.
+starting position is advanced after a match failure for an unanchored pattern.
</P>
<P>
-When PCRE2_NEWLINE_CRLF, PCRE2_NEWLINE_ANYCRLF, or PCRE2_NEWLINE_ANY is set,
-and a match attempt for an unanchored pattern fails when the current position
-is at a CRLF sequence, and the pattern contains no explicit matches for CR or
-LF characters, the match position is advanced by two characters instead of one,
-in other words, to after the CRLF.
+When PCRE2_NEWLINE_CRLF, PCRE2_NEWLINE_ANYCRLF, or PCRE2_NEWLINE_ANY is set as
+the newline convention, and a match attempt for an unanchored pattern fails
+when the current starting position is at a CRLF sequence, and the pattern
+contains no explicit matches for CR or LF characters, the match position is
+advanced by two characters instead of one, in other words, to after the CRLF.
</P>
<P>
The above rule is a compromise that makes the most common cases work as
@@ -1948,8 +1954,8 @@
<P>
An explicit match for CR of LF is either a literal appearance of one of those
characters in the pattern, or one of the \r or \n escape sequences. Implicit
-matches such as [^X] do not count, nor does \s (which includes CR and LF in
-the characters that it matches).
+matches such as [^X] do not count, nor does \s, even though it includes CR and
+LF in the characters that it matches.
</P>
<P>
Notwithstanding the above, anomalous effects may still occur when CRLF is a
@@ -1967,16 +1973,16 @@
addition, further substrings from the subject may be picked out by
parenthesized parts of the pattern. Following the usage in Jeffrey Friedl's
book, this is called "capturing" in what follows, and the phrase "capturing
-subpattern" is used for a fragment of a pattern that picks out a substring.
-PCRE2 supports several other kinds of parenthesized subpattern that do not
-cause substrings to be captured. The <b>pcre2_pattern_info()</b> function can be
-used to find out how many capturing subpatterns there are in a compiled
-pattern.
+subpattern" or "capturing group" is used for a fragment of a pattern that picks
+out a substring. PCRE2 supports several other kinds of parenthesized subpattern
+that do not cause substrings to be captured. The <b>pcre2_pattern_info()</b>
+function can be used to find out how many capturing subpatterns there are in a
+compiled pattern.
</P>
<P>
The overall matched string and any captured substrings are returned to the
-caller via a vector of PCRE2_SIZE values, called the <b>ovector</b>. This is
-contained within the
+caller via a vector of PCRE2_SIZE values. This is called the <b>ovector</b>, and
+is contained within the
<a href="#matchdatablock">match data block.</a>
You can obtain direct access to the ovector by calling
<b>pcre2_get_ovector_pointer()</b> to find its address, and
@@ -2045,9 +2051,7 @@
<b>pcre2_match()</b>. The other elements retain whatever values they previously
had.
<a name="matchotherdata"></a></P>
-<br><b>
-Other information about the match
-</b><br>
+<br><a name="SEC25" href="#TOC1">OTHER INFORMATION ABOUT A MATCH</a><br>
<P>
<b>PCRE2_SPTR pcre2_get_mark(pcre2_match_data *<i>match_data</i>);</b>
<br>
@@ -2055,7 +2059,7 @@
<b>PCRE2_SIZE pcre2_get_startchar(pcre2_match_data *<i>match_data</i>);</b>
</P>
<P>
-In addition to the offsets in the ovector, other information about a match is
+As well as the offsets in the ovector, other information about a match is
retained in the match data block and can be retrieved by the above functions.
</P>
<P>
@@ -2071,9 +2075,7 @@
escape sequence. After a partial match, however, this value is always the same
as <i>ovector[0]</i> because \K does not affect the result of a partial match.
<a name="errorlist"></a></P>
-<br><b>
-Error return values from <b>pcre2_match()</b>
-</b><br>
+<br><a name="SEC26" href="#TOC1">ERROR RETURNS FROM <b>pcre2_match()</b></a><br>
<P>
If <b>pcre2_match()</b> fails, it returns a negative number. This can be
converted to a text string by calling <b>pcre2_get_error_message()</b>. Negative
@@ -2108,7 +2110,7 @@
<pre>
PCRE2_ERROR_BADOFFSET
</pre>
-The value of <i>startoffset</i> greater than the length of the subject.
+The value of <i>startoffset</i> was greater than the length of the subject.
<pre>
PCRE2_ERROR_BADOPTION
</pre>
@@ -2175,14 +2177,14 @@
subpattern has been called recursively for the second time at the same position
in the subject string. Some simple patterns that might do this are detected and
faulted at compile time, but more complicated cases, in particular mutual
-recursions between two different subpatterns, cannot be detected until run
-time.
+recursions between two different subpatterns, cannot be detected until matching
+is attempted.
<pre>
PCRE2_ERROR_RECURSIONLIMIT
</pre>
The internal recursion limit was reached.
<a name="extractbynumber"></a></P>
-<br><a name="SEC25" href="#TOC1">EXTRACTING CAPTURED SUBSTRINGS BY NUMBER</a><br>
+<br><a name="SEC27" href="#TOC1">EXTRACTING CAPTURED SUBSTRINGS BY NUMBER</a><br>
<P>
<b>int pcre2_substring_length_bynumber(pcre2_match_data *<i>match_data</i>,</b>
<b> unsigned int <i>number</i>, PCRE2_SIZE *<i>length</i>);</b>
@@ -2228,8 +2230,8 @@
<P>
The final arguments of <b>pcre2_substring_copy_bynumber()</b> are a pointer to
the buffer and a pointer to a variable that contains its length in code units.
-This is updated to contain the actual number of code units used, excluding the
-terminating zero.
+This is updated to contain the actual number of code units used for the
+extracted substring, excluding the terminating zero.
</P>
<P>
For <b>pcre2_substring_get_bynumber()</b> the third and fourth arguments point
@@ -2254,7 +2256,7 @@
that number did not participate in the match, or because the ovector was too
small to capture that group.
</P>
-<br><a name="SEC26" href="#TOC1">EXTRACTING A LIST OF ALL CAPTURED SUBSTRINGS</a><br>
+<br><a name="SEC28" href="#TOC1">EXTRACTING A LIST OF ALL CAPTURED SUBSTRINGS</a><br>
<P>
<b>int pcre2_substring_list_get(pcre2_match_data *<i>match_data</i>,</b>
<b>" PCRE2_UCHAR ***<i>listptr</i>, PCRE2_SIZE **<i>lengthsptr</i>);</b>
@@ -2264,10 +2266,11 @@
</P>
<P>
The <b>pcre2_substring_list_get()</b> function extracts all available substrings
-and builds a list of pointers to them, and a second list that contains their
-lengths (in code units), excluding a terminating zero that is added to each of
-them. All this is done in a single block of memory that is obtained using the
-same memory allocation function that was used to get the match data block.
+and builds a list of pointers to them. It also (optionally) builds a second
+list that contains their lengths (in code units), excluding a terminating zero
+that is added to each of them. All this is done in a single block of memory
+that is obtained using the same memory allocation function that was used to get
+the match data block.
</P>
<P>
The address of the memory block is returned via <i>listptr</i>, which is also
@@ -2285,10 +2288,10 @@
capturing subpattern number <i>n+1</i> matches some part of the subject, but
subpattern <i>n</i> has not been used at all, it returns an empty string. This
can be distinguished from a genuine zero-length substring by inspecting the
-appropriate offset in the ovector, which contains PCRE2_UNSET for unset
+appropriate offset in the ovector, which contain PCRE2_UNSET for unset
substrings.
<a name="extractbyname"></a></P>
-<br><a name="SEC27" href="#TOC1">EXTRACTING CAPTURED SUBSTRINGS BY NAME</a><br>
+<br><a name="SEC29" href="#TOC1">EXTRACTING CAPTURED SUBSTRINGS BY NAME</a><br>
<P>
<b>int pcre2_substring_number_from_name(const pcre2_code *<i>code</i>,</b>
<b> PCRE2_SPTR <i>name</i>);</b>
@@ -2324,11 +2327,10 @@
</P>
<P>
Given the number, you can extract the substring directly, or use one of the
-functions described in the previous section. For convenience, there are also
-"byname" functions that correspond to the "bynumber" functions, the only
-difference being that the second argument is a name instead of a number.
-However, if PCRE2_DUPNAMES is set and there are duplicate names,
-the behaviour may not be what you want (see the next section).
+functions described above. For convenience, there are also "byname" functions
+that correspond to the "bynumber" functions, the only difference being that the
+second argument is a name instead of a number. However, if PCRE2_DUPNAMES is
+set and there are duplicate names, the behaviour may not be what you want.
</P>
<P>
<b>Warning:</b> If the pattern uses the (?| feature to set up multiple
@@ -2341,7 +2343,7 @@
numbers. For this reason, the use of different names for subpatterns of the
same number causes an error at compile time.
</P>
-<br><a name="SEC28" href="#TOC1">CREATING A NEW STRING WITH SUBSTITUTIONS</a><br>
+<br><a name="SEC30" href="#TOC1">CREATING A NEW STRING WITH SUBSTITUTIONS</a><br>
<P>
<b>int pcre2_substitute(const pcre2_code *<i>code</i>, PCRE2_SPTR <i>subject</i>,</b>
<b> PCRE2_SIZE <i>length</i>, PCRE2_SIZE <i>startoffset</i>,</b>
@@ -2368,8 +2370,8 @@
Either a group number or a group name can be given for <n>. Curly brackets are
required only if the following character would be interpreted as part of the
number or name. The number may be zero to include the entire matched string.
-For example, if the pattern a(b)c is matched with "[abc]" and the replacement
-string "+$1$0$1+", the result is "[+babcb+]". Group insertion is done by
+For example, if the pattern a(b)c is matched with "=abc=" and the replacement
+string "+$1$0$1+", the result is "=+babcb+=". Group insertion is done by
calling <b>pcre2_copy_byname()</b> or <b>pcre2_copy_bynumber()</b> as
appropriate.
</P>
@@ -2402,7 +2404,7 @@
replacement string (unrecognized sequence following a dollar sign), and
PCRE2_ERROR_NOMEMORY is returned if the output buffer is not big enough.
</P>
-<br><a name="SEC29" href="#TOC1">DUPLICATE SUBPATTERN NAMES</a><br>
+<br><a name="SEC31" href="#TOC1">DUPLICATE SUBPATTERN NAMES</a><br>
<P>
<b>int pcre2_substring_nametable_scan(const pcre2_code *<i>code</i>,</b>
<b> PCRE2_SPTR <i>name</i>, PCRE2_SPTR *<i>first</i>, PCRE2_SPTR *<i>last</i>);</b>
@@ -2423,19 +2425,21 @@
When duplicates are present, <b>pcre2_substring_copy_byname()</b> and
<b>pcre2_substring_get_byname()</b> return the first substring corresponding to
the given name that is set. If none are set, PCRE2_ERROR_NOSUBSTRING is
-returned. The <b>pcre2_substring_number_from_name()</b> function returns one of
-the numbers that are associated with the name, but it is not defined which it
-is.
+returned. The <b>pcre2_substring_number_from_name()</b> function returns
+the error PCRE2_ERROR_NOUNIQUESUBSTRING.
</P>
<P>
If you want to get full details of all captured substrings for a given name,
you must use the <b>pcre2_substring_nametable_scan()</b> function. The first
argument is the compiled pattern, and the second is the name. If the third and
-fourth arguments are NULL, the function returns a group number (it is not
-defined which). Otherwise, the third and fourth arguments must be pointers to
+fourth arguments are NULL, the function returns a group number for a unique
+name, or PCRE2_ERROR_NOUNIQUESUBSTRING otherwise.
+</P>
+<P>
+When the third and fourth arguments are not NULL, they must be pointers to
variables that are updated by the function. After it has run, they point to the
first and last entries in the name-to-number table for the given name, and the
-function returns the length of each entry. In both cases,
+function returns the length of each entry in code units. In both cases,
PCRE2_ERROR_NOSUBSTRING is returned if there are no entries for the given name.
</P>
<P>
@@ -2445,14 +2449,14 @@
Given all the relevant entries for the name, you can extract each of their
numbers, and hence the captured data.
</P>
-<br><a name="SEC30" href="#TOC1">FINDING ALL POSSIBLE MATCHES</a><br>
+<br><a name="SEC32" href="#TOC1">FINDING ALL POSSIBLE MATCHES AT ONE POSITION</a><br>
<P>
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
-want to find all possible matches, or the longest possible match at a given
-position, consider using the alternative matching function (see below) instead.
-If you cannot use the alternative function, you can kludge it up by making use
-of the callout facility, which is described in the
+when it finds the first match at a given point in the subject. If you want to
+find all possible matches, or the longest possible match at a given position,
+consider using the alternative matching function (see below) instead. If you
+cannot use the alternative function, you can kludge it up by making use of the
+callout facility, which is described in the
<a href="pcre2callout.html"><b>pcre2callout</b></a>
documentation.
</P>
@@ -2463,7 +2467,7 @@
other alternatives. Ultimately, when it runs out of matches,
<b>pcre2_match()</b> will yield PCRE2_ERROR_NOMATCH.
<a name="dfamatch"></a></P>
-<br><a name="SEC31" href="#TOC1">MATCHING A PATTERN: THE ALTERNATIVE FUNCTION</a><br>
+<br><a name="SEC33" href="#TOC1">MATCHING A PATTERN: THE ALTERNATIVE FUNCTION</a><br>
<P>
<b>int pcre2_dfa_match(const pcre2_code *<i>code</i>, PCRE2_SPTR <i>subject</i>,</b>
<b> PCRE2_SIZE <i>length</i>, PCRE2_SIZE <i>startoffset</i>,</b>
@@ -2591,11 +2595,10 @@
<P>
NOTE: PCRE2'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 in
-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
-PCRE2_NO_AUTO_POSSESS option when compiling.
+pattern "a\d+" is compiled as if it were "a\d++". 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 auch as "a\d+?" or set
+the PCRE2_NO_AUTO_POSSESS option when compiling.
</P>
<br><b>
Error returns from <b>pcre2_dfa_match()</b>
@@ -2633,29 +2636,29 @@
<pre>
PCRE2_ERROR_DFA_BADRESTART
</pre>
-When <b>pcre2_dfa_match()</b> is called with the <b>pcre2_dfa_RESTART</b> option,
+When <b>pcre2_dfa_match()</b> is called with the <b>PCRE2_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>
-<br><a name="SEC32" href="#TOC1">SEE ALSO</a><br>
+<br><a name="SEC34" href="#TOC1">SEE ALSO</a><br>
<P>
-<b>pcre2build</b>(3), <b>pcre2libs</b>(3), <b>pcre2callout</b>(3),
+<b>pcre2build</b>(3), <b>pcre2callout</b>(3), <b>pcre2demo(3)</b>,
<b>pcre2matching</b>(3), <b>pcre2partial</b>(3), <b>pcre2posix</b>(3),
-<b>pcre2demo(3)</b>, <b>pcre2sample</b>(3), <b>pcre2stack</b>(3).
+<b>pcre2sample</b>(3), <b>pcre2stack</b>(3), <b>pcre2unicode</b>(3).
</P>
-<br><a name="SEC33" href="#TOC1">AUTHOR</a><br>
+<br><a name="SEC35" href="#TOC1">AUTHOR</a><br>
<P>
Philip Hazel
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
-<br><a name="SEC34" href="#TOC1">REVISION</a><br>
+<br><a name="SEC36" href="#TOC1">REVISION</a><br>
<P>
-Last updated: 11 November 2014
+Last updated: 21 November 2014
<br>
Copyright © 1997-2014 University of Cambridge.
<br>
Modified: code/trunk/doc/html/pcre2build.html
===================================================================
--- code/trunk/doc/html/pcre2build.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2build.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -461,7 +461,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><a name="SEC21" href="#TOC1">REVISION</a><br>
Modified: code/trunk/doc/html/pcre2callout.html
===================================================================
--- code/trunk/doc/html/pcre2callout.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2callout.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -256,7 +256,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><a name="SEC7" href="#TOC1">REVISION</a><br>
Modified: code/trunk/doc/html/pcre2compat.html
===================================================================
--- code/trunk/doc/html/pcre2compat.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2compat.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -207,7 +207,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><b>
Modified: code/trunk/doc/html/pcre2grep.html
===================================================================
--- code/trunk/doc/html/pcre2grep.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2grep.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -745,7 +745,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><a name="SEC14" href="#TOC1">REVISION</a><br>
Modified: code/trunk/doc/html/pcre2jit.html
===================================================================
--- code/trunk/doc/html/pcre2jit.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2jit.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -413,7 +413,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><a name="SEC13" href="#TOC1">REVISION</a><br>
Modified: code/trunk/doc/html/pcre2limits.html
===================================================================
--- code/trunk/doc/html/pcre2limits.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2limits.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -73,7 +73,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><b>
Modified: code/trunk/doc/html/pcre2matching.html
===================================================================
--- code/trunk/doc/html/pcre2matching.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2matching.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -227,7 +227,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><a name="SEC8" href="#TOC1">REVISION</a><br>
Modified: code/trunk/doc/html/pcre2partial.html
===================================================================
--- code/trunk/doc/html/pcre2partial.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2partial.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -450,7 +450,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><a name="SEC10" href="#TOC1">REVISION</a><br>
Modified: code/trunk/doc/html/pcre2pattern.html
===================================================================
--- code/trunk/doc/html/pcre2pattern.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2pattern.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -3231,7 +3231,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><a name="SEC30" href="#TOC1">REVISION</a><br>
Modified: code/trunk/doc/html/pcre2perform.html
===================================================================
--- code/trunk/doc/html/pcre2perform.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2perform.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -180,7 +180,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><b>
Modified: code/trunk/doc/html/pcre2posix.html
===================================================================
--- code/trunk/doc/html/pcre2posix.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2posix.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -278,7 +278,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><a name="SEC9" href="#TOC1">REVISION</a><br>
Modified: code/trunk/doc/html/pcre2sample.html
===================================================================
--- code/trunk/doc/html/pcre2sample.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2sample.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -90,7 +90,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><b>
Modified: code/trunk/doc/html/pcre2stack.html
===================================================================
--- code/trunk/doc/html/pcre2stack.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2stack.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -33,6 +33,13 @@
current call (a "tail recursion"), the function is just restarted instead.
</P>
<P>
+Each time the internal <b>match()</b> function is called recursively, it uses
+memory from the process stack. For certain kinds of pattern and data, very
+large amounts of stack may be needed, despite the recognition of "tail
+recursion". Note that if PCRE2 is compiled with the -fsanitize=address option
+of the GCC compiler, the stack requirements are greatly increased.
+</P>
+<P>
The above comments apply when <b>pcre2_match()</b> is run in its normal
interpretive manner. If the compiled pattern was processed by
<b>pcre2_jit_compile()</b>, and just-in-time compiling was successful, and the
@@ -61,10 +68,7 @@
Reducing <b>pcre2_match()</b>'s stack usage
</b><br>
<P>
-Each time that the internal <b>match()</b> function is called recursively, it
-uses memory from the process stack. For certain kinds of pattern and data, very
-large amounts of stack may be needed, despite the recognition of "tail
-recursion". You can often reduce the amount of recursion, and therefore the
+You can often reduce the amount of recursion, and therefore the
amount of stack used, by modifying the pattern that is being matched. Consider,
for example, this pattern:
<pre>
@@ -187,14 +191,14 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><b>
REVISION
</b><br>
<P>
-Last updated: 20 October 2014
+Last updated: 21 November 2014
<br>
Copyright © 1997-2014 University of Cambridge.
<br>
Modified: code/trunk/doc/html/pcre2syntax.html
===================================================================
--- code/trunk/doc/html/pcre2syntax.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2syntax.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -548,7 +548,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><a name="SEC27" href="#TOC1">REVISION</a><br>
Modified: code/trunk/doc/html/pcre2test.html
===================================================================
--- code/trunk/doc/html/pcre2test.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2test.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -1301,7 +1301,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><a name="SEC20" href="#TOC1">REVISION</a><br>
Modified: code/trunk/doc/html/pcre2unicode.html
===================================================================
--- code/trunk/doc/html/pcre2unicode.html 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/html/pcre2unicode.html 2014-11-21 16:45:06 UTC (rev 157)
@@ -254,7 +254,7 @@
<br>
University Computing Service
<br>
-Cambridge CB2 3QH, England.
+Cambridge, England.
<br>
</P>
<br><b>
Modified: code/trunk/doc/pcre2.3
===================================================================
--- code/trunk/doc/pcre2.3 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/pcre2.3 2014-11-21 16:45:06 UTC (rev 157)
@@ -146,7 +146,7 @@
pcre2matching discussion of the two matching algorithms
pcre2partial details of the partial matching facility
.\" JOIN
- pcre2pattern syntax and semantics of supported regular
+ pcre2pattern syntax and semantics of supported regular
expression patterns
pcre2perform discussion of performance issues
pcre2posix the POSIX-compatible C API for the 8-bit library
Modified: code/trunk/doc/pcre2.txt
===================================================================
--- code/trunk/doc/pcre2.txt 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/pcre2.txt 2014-11-21 16:45:06 UTC (rev 157)
@@ -22,9 +22,9 @@
pattern matching using the same syntax and semantics as Perl, with just
a few differences. Some features that appeared in Python and the origi-
nal PCRE before they appeared in Perl are also available using the
- Python syntax, there is some support for one or two .NET and Oniguruma
- syntax items, and there are options for requesting some minor changes
- that give better ECMAScript (aka JavaScript) compatibility.
+ Python syntax. There is also some support for one or two .NET and Onig-
+ uruma syntax items, and there are options for requesting some minor
+ changes that give better ECMAScript (aka JavaScript) compatibility.
The source code for PCRE2 can be compiled to support 8-bit, 16-bit, or
32-bit code units, which means that up to three separate libraries may
@@ -33,7 +33,7 @@
tively. In all three cases, strings can be interpreted either as one
character per code unit, or as UTF-encoded Unicode, with support for
Unicode general category properties. Unicode support is optional at
- build time (but is the default); however, processing strings as UTF
+ build time (but is the default). However, processing strings as UTF
code units must be enabled explicitly at run time. The version of Uni-
code in use can be discovered by running
@@ -124,22 +124,21 @@
pcre2compat discussion of Perl compatibility
pcre2demo a demonstration C program that uses PCRE2
pcre2grep description of the pcre2grep command (8-bit only)
- pcre2jit discussion of the just-in-time optimization sup-
- port
+ pcre2jit discussion of just-in-time optimization support
pcre2limits details of size and other limits
pcre2matching discussion of the two matching algorithms
pcre2partial details of the partial matching facility
- pcre2pattern syntax and semantics of supported
- regular expressions
+ pcre2pattern syntax and semantics of supported regular
+ expression patterns
pcre2perform discussion of performance issues
pcre2posix the POSIX-compatible C API for the 8-bit library
pcre2sample discussion of the pcre2demo program
pcre2stack discussion of stack usage
pcre2syntax quick syntax reference
- pcre2test description of the pcre2test testing command
+ pcre2test description of the pcre2test command
pcre2unicode discussion of Unicode and UTF support
- In the "man" and HTML formats, there is also a short page for each C
+ In the "man" and HTML formats, there is also a short page for each C
library function, listing its arguments and results.
@@ -147,16 +146,16 @@
Philip Hazel
University Computing Service
- Cambridge CB2 3QH, England.
+ Cambridge, England.
- Putting an actual email address here is a spam magnet. If you want to
- email me, use my two initials, followed by the two digits 10, at the
+ Putting an actual email address here is a spam magnet. If you want to
+ email me, use my two initials, followed by the two digits 10, at the
domain cam.ac.uk.
REVISION
- Last updated: 03 November 2014
+ Last updated: 18 November 2014
Copyright (c) 1997-2014 University of Cambridge.
------------------------------------------------------------------------------
@@ -506,100 +505,97 @@
Each of the first three conventions is used by at least one operating
system as its standard newline sequence. When PCRE2 is built, a default
can be specified. The default default is LF, which is the Unix stan-
- dard. When PCRE2 is run, the default can be overridden, either when a
- pattern is compiled, or when it is matched.
+ dard. However, the newline convention can be changed by an application
+ when calling pcre2_compile(), or it can be specified by special text at
+ the start of the pattern itself; this overrides any other settings. See
+ the pcre2pattern page for details of the special character sequences.
- The newline convention can be changed when calling pcre2_compile(), or
- it can be specified by special text at the start of the pattern itself;
- this overrides any other settings. See the pcre2pattern page for
- details of the special character sequences.
-
- In the PCRE2 documentation the word "newline" is used to mean "the
+ In the PCRE2 documentation the word "newline" is used to mean "the
character or pair of characters that indicate a line break". The choice
- of newline convention affects the handling of the dot, circumflex, and
+ of newline convention affects the handling of the dot, circumflex, and
dollar metacharacters, the handling of #-comments in /x mode, and, when
- CRLF is a recognized line ending sequence, the match position advance-
+ CRLF is a recognized line ending sequence, the match position advance-
ment for a non-anchored pattern. There is more detail about this in the
section on pcre2_match() options below.
- The choice of newline convention does not affect the interpretation of
- the \n or \r escape sequences, nor does it affect what \R matches,
- which has its own separate control.
+ The choice of newline convention does not affect the interpretation of
+ the \n or \r escape sequences, nor does it affect what \R matches; this
+ has its own separate convention.
MULTITHREADING
- In a multithreaded application it is important to keep thread-specific
- data separate from data that can be shared between threads. The PCRE2
- library code itself is thread-safe: it contains no static or global
- variables. The API is designed to be fairly simple for non-threaded
- applications while at the same time ensuring that multithreaded appli-
+ In a multithreaded application it is important to keep thread-specific
+ data separate from data that can be shared between threads. The PCRE2
+ library code itself is thread-safe: it contains no static or global
+ variables. The API is designed to be fairly simple for non-threaded
+ applications while at the same time ensuring that multithreaded appli-
cations can use it.
There are several different blocks of data that are used to pass infor-
- mation between the application and the PCRE libraries.
+ mation between the application and the PCRE2 libraries.
(1) A pointer to the compiled form of a pattern is returned to the user
when pcre2_compile() is successful. The data in the compiled pattern is
- fixed, and does not change when the pattern is matched. Therefore, it
- is thread-safe, that is, the same compiled pattern can be used by more
+ fixed, and does not change when the pattern is matched. Therefore, it
+ is thread-safe, that is, the same compiled pattern can be used by more
than one thread simultaneously. An application can compile all its pat-
- terns at the start, before forking off multiple threads that use them.
- However, if the just-in-time optimization feature is being used, it
- needs separate memory stack areas for each thread. See the pcre2jit
+ terns at the start, before forking off multiple threads that use them.
+ However, if the just-in-time optimization feature is being used, it
+ needs separate memory stack areas for each thread. See the pcre2jit
documentation for more details.
- (2) The next section below introduces the idea of "contexts" in which
+ (2) The next section below introduces the idea of "contexts" in which
PCRE2 functions are called. A context is nothing more than a collection
of parameters that control the way PCRE2 operates. Grouping a number of
parameters together in a context is a convenient way of passing them to
- a PCRE2 function without using lots of arguments. The parameters that
- are stored in contexts are in some sense "advanced features" of the
+ a PCRE2 function without using lots of arguments. The parameters that
+ are stored in contexts are in some sense "advanced features" of the
API. Many straightforward applications will not need to use contexts.
In a multithreaded application, if the parameters in a context are val-
- ues that are never changed, the same context can be used by all the
+ ues that are never changed, the same context can be used by all the
threads. However, if any thread needs to change any value in a context,
it must make its own thread-specific copy.
(3) The matching functions need a block of memory for working space and
- for storing the results of a match. This includes details of what was
- matched, as well as additional information such as the name of a
- (*MARK) setting. Each thread must provide its own version of this mem-
+ for storing the results of a match. This includes details of what was
+ matched, as well as additional information such as the name of a
+ (*MARK) setting. Each thread must provide its own version of this mem-
ory.
PCRE2 CONTEXTS
- Some PCRE2 functions have a lot of parameters, many of which are used
- only by specialist applications, for example, those that use custom
- memory management or non-standard character tables. To keep function
- argument lists at a reasonable size, and at the same time to keep the
- API extensible, "uncommon" parameters are passed to certain functions
- in a context instead of directly. A context is just a block of memory
- that holds the parameter values. Applications that do not need to
- adjust any of the context parameters can pass NULL when a context
+ Some PCRE2 functions have a lot of parameters, many of which are used
+ only by specialist applications, for example, those that use custom
+ memory management or non-standard character tables. To keep function
+ argument lists at a reasonable size, and at the same time to keep the
+ API extensible, "uncommon" parameters are passed to certain functions
+ in a context instead of directly. A context is just a block of memory
+ that holds the parameter values. Applications that do not need to
+ adjust any of the context parameters can pass NULL when a context
pointer is required.
- There are three different types of context: a general context that is
- relevant for several PCRE2 operations, a compile-time context, and a
+ There are three different types of context: a general context that is
+ relevant for several PCRE2 operations, a compile-time context, and a
match-time context.
The general context
- At present, this context just contains pointers to (and data for)
- external memory management functions that are called from several
+ At present, this context just contains pointers to (and data for)
+ external memory management functions that are called from several
places in the PCRE2 library. The context is named `general' rather than
- specifically `memory' because in future other fields may be added. If
- you do not want to supply your own custom memory management functions,
- you do not need to bother with a general context. A general context is
+ specifically `memory' because in future other fields may be added. If
+ you do not want to supply your own custom memory management functions,
+ you do not need to bother with a general context. A general context is
created by:
pcre2_general_context *pcre2_general_context_create(
void *(*private_malloc)(PCRE2_SIZE, void *),
void (*private_free)(void *, void *), void *memory_data);
- The two function pointers specify custom memory management functions,
+ The two function pointers specify custom memory management functions,
whose prototypes are:
void *private_malloc(PCRE2_SIZE, void *);
@@ -607,16 +603,16 @@
Whenever code in PCRE2 calls these functions, the final argument is the
value of memory_data. Either of the first two arguments of the creation
- function may be NULL, in which case the system memory management func-
- tions malloc() and free() are used. (This is not currently useful, as
- there are no other fields in a general context, but in future there
- might be.) The private_malloc() function is used (if supplied) to
- obtain memory for storing the context, and all three values are saved
+ function may be NULL, in which case the system memory management func-
+ tions malloc() and free() are used. (This is not currently useful, as
+ there are no other fields in a general context, but in future there
+ might be.) The private_malloc() function is used (if supplied) to
+ obtain memory for storing the context, and all three values are saved
as part of the context.
- Whenever PCRE2 creates a data block of any kind, the block contains a
- pointer to the free() function that matches the malloc() function that
- was used. When the time comes to free the block, this function is
+ Whenever PCRE2 creates a data block of any kind, the block contains a
+ pointer to the free() function that matches the malloc() function that
+ was used. When the time comes to free the block, this function is
called.
A general context can be copied by calling:
@@ -631,20 +627,20 @@
The compile context
- A compile context is required if you want to change the default values
+ A compile context is required if you want to change the default values
of any of the following compile-time parameters:
- What \R matches (Unicode newlines or CR, LF, CRLF only);
- PCRE2's character tables;
- The newline character sequence;
- The compile time nested parentheses limit;
- An external function for stack checking.
+ What \R matches (Unicode newlines or CR, LF, CRLF only)
+ PCRE2's character tables
+ The newline character sequence
+ The compile time nested parentheses limit
+ An external function for stack checking
- A compile context is also required if you are using custom memory man-
- agement. If none of these apply, just pass NULL as the context argu-
+ A compile context is also required if you are using custom memory man-
+ agement. If none of these apply, just pass NULL as the context argu-
ment of pcre2_compile().
- A compile context is created, copied, and freed by the following func-
+ A compile context is created, copied, and freed by the following func-
tions:
pcre2_compile_context *pcre2_compile_context_create(
@@ -655,19 +651,18 @@
void pcre2_compile_context_free(pcre2_compile_context *ccontext);
- A compile context is created with default values for its parameters.
+ A compile context is created with default values for its parameters.
These can be changed by calling the following functions, which return 0
on success, or PCRE2_ERROR_BADDATA if invalid data is detected.
int pcre2_set_bsr(pcre2_compile_context *ccontext,
uint32_t value);
- The value must be PCRE2_BSR_ANYCRLF, to specify that \R matches only
- CR, LF, or CRLF, or PCRE2_BSR_UNICODE, to specify that \R matches any
- Unicode line ending sequence. The value of this parameter does not
- affect what is compiled; it is just saved with the compiled pattern.
- The value is used by the JIT compiler and by the two interpreted match-
- ing functions, pcre2_match() and pcre2_dfa_match().
+ The value must be PCRE2_BSR_ANYCRLF, to specify that \R matches only
+ CR, LF, or CRLF, or PCRE2_BSR_UNICODE, to specify that \R matches any
+ Unicode line ending sequence. The value is used by the JIT compiler and
+ by the two interpreted matching functions, pcre2_match() and
+ pcre2_dfa_match().
int pcre2_set_character_tables(pcre2_compile_context *ccontext,
const unsigned char *tables);
@@ -763,8 +758,8 @@
from zero for each position in the subject string. This limit is not
relevant to pcre2_dfa_match(), which ignores it.
- When pcre2_match() is called with a pattern that was successfully stud-
- ied with pcre2_jit_compile(), the way that the matching is executed is
+ When pcre2_match() is called with a pattern that was successfully pro-
+ cessed by pcre2_jit_compile(), the way in which matching is executed is
entirely different. However, there is still the possibility of runaway
matching that goes on for a very long time, and so the match_limit
value is also used in this case (but in a different way) to limit how
@@ -819,49 +814,50 @@
remembering backtracking data, instead of recursive function calls that
use the system stack. There is a discussion about PCRE2's stack usage
in the pcre2stack documentation. See the pcre2build documentation for
- details of how to build PCRE2. Using the heap for recursion is a non-
- standard way of building PCRE2, for use in environments that have lim-
- ited stacks. Because of the greater use of memory management,
- pcre2_match() runs more slowly. Functions that are different to the
- general custom memory functions are provided so that special-purpose
- external code can be used for this case, because the memory blocks are
- all the same size. The blocks are retained by pcre2_match() until it is
- about to exit so that they can be re-used when possible during the
- match. In the absence of these functions, the normal custom memory man-
- agement functions are used, if supplied, otherwise the system func-
- tions.
+ details of how to build PCRE2.
+ Using the heap for recursion is a non-standard way of building PCRE2,
+ for use in environments that have limited stacks. Because of the
+ greater use of memory management, pcre2_match() runs more slowly. Func-
+ tions that are different to the general custom memory functions are
+ provided so that special-purpose external code can be used for this
+ case, because the memory blocks are all the same size. The blocks are
+ retained by pcre2_match() until it is about to exit so that they can be
+ re-used when possible during the match. In the absence of these func-
+ tions, the normal custom memory management functions are used, if sup-
+ plied, otherwise the system functions.
+
CHECKING BUILD-TIME OPTIONS
int pcre2_config(uint32_t what, void *where);
- The function pcre2_config() makes it possible for a PCRE2 client to
- discover which optional features have been compiled into the PCRE2
- library. The pcre2build documentation has more details about these
+ The function pcre2_config() makes it possible for a PCRE2 client to
+ discover which optional features have been compiled into the PCRE2
+ library. The pcre2build documentation has more details about these
optional features.
- The first argument for pcre2_config() specifies which information is
- required. The second argument is a pointer to memory into which the
- information is placed. If NULL is passed, the function returns the
- amount of memory that is needed for the requested information. For
- calls that return numerical values, the value is in bytes; when
- requesting these values, where should point to appropriately aligned
- memory. For calls that return strings, the required length is given in
+ The first argument for pcre2_config() specifies which information is
+ required. The second argument is a pointer to memory into which the
+ information is placed. If NULL is passed, the function returns the
+ amount of memory that is needed for the requested information. For
+ calls that return numerical values, the value is in bytes; when
+ requesting these values, where should point to appropriately aligned
+ memory. For calls that return strings, the required length is given in
code units, not counting the terminating zero.
- When requesting information, the returned value from pcre2_config() is
- non-negative on success, or the negative error code PCRE2_ERROR_BADOP-
- TION if the value in the first argument is not recognized. The follow-
+ When requesting information, the returned value from pcre2_config() is
+ non-negative on success, or the negative error code PCRE2_ERROR_BADOP-
+ TION if the value in the first argument is not recognized. The follow-
ing information is available:
PCRE2_CONFIG_BSR
The output is an integer whose value indicates what character sequences
- the \R escape sequence matches by default. A value of 0 means that \R
- matches any Unicode line ending sequence; a value of 1 means that \R
- matches only CR, LF, or CRLF. The default can be overridden when a pat-
- tern is compiled or matched.
+ the \R escape sequence matches by default. A value of PCRE2_BSR_UNICODE
+ means that \R matches any Unicode line ending sequence; a value of
+ PCRE2_BSR_ANYCRLF means that \R matches only CR, LF, or CRLF. The
+ default can be overridden when a pattern is compiled.
PCRE2_CONFIG_JIT
@@ -870,98 +866,98 @@
PCRE2_CONFIG_JITTARGET
- The where argument should point to a buffer that is at least 48 code
- units long. (The exact length needed can be found by calling pcre2_con-
- fig() with where set to NULL.) The buffer is filled with a string that
- 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, PCRE2_ERROR_BADOPTION is returned, otherwise
- the number of code units used is returned. This is the length of the
- string, plus one unit for the terminating zero.
+ The where argument should point to a buffer that is at least 48 code
+ units long. (The exact length required can be found by calling
+ pcre2_config() with where set to NULL.) The buffer is filled with a
+ string that 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, PCRE2_ERROR_BADOPTION is
+ returned, otherwise the number of code units used is returned. This is
+ the length of the string, plus one unit for the terminating zero.
PCRE2_CONFIG_LINKSIZE
- The output is an integer that contains the number of bytes used for
+ The output is an integer that contains the number of bytes used for
internal linkage in compiled regular expressions. When PCRE2 is config-
- ured, the value can be set to 2, 3, or 4, with the default being 2.
+ ured, the value can be set to 2, 3, or 4, with the default being 2.
This is the value that is returned by pcre2_config(). However, when the
- 16-bit library is compiled, a value of 3 is rounded up to 4, and when
- the 32-bit library is compiled, internal linkages always use 4 bytes,
+ 16-bit library is compiled, a value of 3 is rounded up to 4, and when
+ the 32-bit library is compiled, internal linkages always use 4 bytes,
so the configured value is not relevant.
The default value of 2 for the 8-bit and 16-bit libraries is sufficient
- for all but the most massive patterns, since it allows the size of the
+ for all but the most massive patterns, since it allows the size of the
compiled pattern to be up to 64K code units. Larger values allow larger
- regular expressions to be compiled by those two libraries, but at the
+ regular expressions to be compiled by those two libraries, but at the
expense of slower matching.
PCRE2_CONFIG_MATCHLIMIT
The output is an unsigned long integer that gives the default limit for
- the number of internal matching function calls in a pcre2_match() exe-
+ the number of internal matching function calls in a pcre2_match() exe-
cution. Further details are given with pcre2_match() below.
PCRE2_CONFIG_NEWLINE
- The output is an integer whose value specifies the default character
+ The output is an integer whose value specifies the default character
sequence that is recognized as meaning "newline". The values are:
- 1 Carriage return (CR)
- 2 Linefeed (LF)
- 3 Carriage return, linefeed (CRLF)
- 4 Any Unicode line ending
- 5 Any of CR, LF, or CRLF
+ PCRE2_NEWLINE_CR Carriage return (CR)
+ PCRE2_NEWLINE_LF Linefeed (LF)
+ PCRE2_NEWLINE_CRLF Carriage return, linefeed (CRLF)
+ PCRE2_NEWLINE_ANY Any Unicode line ending
+ PCRE2_NEWLINE_ANYCRLF Any of CR, LF, or CRLF
- The default should normally correspond to the standard sequence for
+ The default should normally correspond to the standard sequence for
your operating system.
PCRE2_CONFIG_PARENSLIMIT
- The output is an unsigned 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 com-
- piled. It is specified when PCRE2 is built; the default is 250. This
- limit does not take into account the stack that may already be used by
- the calling application. For finer control over compilation stack
+ The output is an unsigned 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 com-
+ piled. It is specified when PCRE2 is built; the default is 250. This
+ limit does not take into account the stack that may already be used by
+ the calling application. For finer control over compilation stack
usage, see pcre2_set_compile_recursion_guard().
PCRE2_CONFIG_RECURSIONLIMIT
The output is an unsigned long integer that gives the default limit for
the depth of recursion when calling the internal matching function in a
- pcre2_match() execution. Further details are given with pcre2_match()
+ pcre2_match() execution. Further details are given with pcre2_match()
below.
PCRE2_CONFIG_STACKRECURSE
- The output is an integer that is set to one if internal recursion when
- running pcre2_match() is implemented by recursive function calls that
- use the system stack to remember their state. This is the usual way
+ The output is an integer that is set to one if internal recursion when
+ running pcre2_match() is implemented by recursive function calls that
+ use the system stack to remember their state. This is the usual way
that PCRE2 is compiled. The output is zero if PCRE2 was compiled to use
blocks of data on the heap instead of recursive function calls.
PCRE2_CONFIG_UNICODE_VERSION
- The where argument should point to a buffer that is at least 24 code
- units long. (The exact length needed can be found by calling pcre2_con-
- fig() with where set to NULL.) If PCRE2 has been compiled without Uni-
- code support, the buffer is filled with the text "Unicode not sup-
- ported". Otherwise, the Unicode version string (for example, "7.0.0")
- is inserted. The number of code units used is returned. This is the
- length of the string plus one unit for the terminating zero.
+ The where argument should point to a buffer that is at least 24 code
+ units long. (The exact length required can be found by calling
+ pcre2_config() with where set to NULL.) If PCRE2 has been compiled
+ without Unicode support, the buffer is filled with the text "Unicode
+ not supported". Otherwise, the Unicode version string (for example,
+ "7.0.0") is inserted. The number of code units used is returned. This
+ is the length of the string plus one unit for the terminating zero.
PCRE2_CONFIG_UNICODE
- The output is an integer that is set to one if Unicode support is
- available; otherwise it is set to zero. Unicode support implies UTF
+ The output is an integer that is set to one if Unicode support is
+ available; otherwise it is set to zero. Unicode support implies UTF
support.
PCRE2_CONFIG_VERSION
- The where argument should point to a buffer that is at least 12 code
- units long. (The exact length needed can be found by calling pcre2_con-
- fig() with where set to NULL.) The buffer is filled with the PCRE2 ver-
- sion string, zero-terminated. The number of code units used is
+ The where argument should point to a buffer that is at least 12 code
+ units long. (The exact length required can be found by calling
+ pcre2_config() with where set to NULL.) The buffer is filled with the
+ PCRE2 version string, zero-terminated. The number of code units used is
returned. This is the length of the string plus one unit for the termi-
nating zero.
@@ -974,49 +970,51 @@
pcre2_code_free(pcre2_code *code);
- This function compiles a pattern, defined by a pointer to a string of
- code units and a length, into an internal form. If the pattern is zero-
- terminated, the length should be specified as PCRE2_ZERO_TERMINATED.
- The function returns a pointer to a block of memory that contains the
- compiled pattern and related data. The caller must free the memory by
- calling pcre2_code_free() when it is no longer needed.
+ The pcre2_compile() function compiles a pattern into an internal form.
+ The pattern is defined by a pointer to a string of code units and a
+ length, If the pattern is zero-terminated, the length can be specified
+ as PCRE2_ZERO_TERMINATED. The function returns a pointer to a block of
+ memory that contains the compiled pattern and related data. The caller
+ must free the memory by calling pcre2_code_free() when it is no longer
+ needed.
- If the compile context argument ccontext is NULL, the memory is
- obtained by calling malloc(). Otherwise, it is obtained from the same
- memory function that was used for the compile context.
+ If the compile context argument ccontext is NULL, memory for the com-
+ piled pattern is obtained by calling malloc(). Otherwise, it is
+ obtained from the same memory function that was used for the compile
+ context.
The options argument contains various bit settings that affect the com-
- pilation. It should be zero if no options are required. The available
- options are described below. Some of them (in particular, those that
- are compatible with Perl, but some others as well) can also be set and
- unset from within the pattern (see the detailed description in the
+ pilation. It should be zero if no options are required. The available
+ options are described below. Some of them (in particular, those that
+ are compatible with Perl, but some others as well) can also be set and
+ unset from within the pattern (see the detailed description in the
pcre2pattern documentation).
- For those options that can be different in different parts of the pat-
- tern, the contents of the options argument specifies their settings at
- the start of compilation. The PCRE2_ANCHORED and PCRE2_NO_UTF_CHECK
+ For those options that can be different in different parts of the pat-
+ tern, the contents of the options argument specifies their settings at
+ the start of compilation. The PCRE2_ANCHORED and PCRE2_NO_UTF_CHECK
options can be set at the time of matching as well as at compile time.
- Other, less frequently required compile-time parameters (for example,
+ Other, less frequently required compile-time parameters (for example,
the newline setting) can be provided in a compile context (as described
above).
If errorcode or erroroffset is NULL, pcre2_compile() returns NULL imme-
- diately. Otherwise, if compilation of a pattern fails, pcre2_compile()
+ diately. Otherwise, if compilation of a pattern fails, pcre2_compile()
returns NULL, having set these variables to an error code and an offset
- (number of code units) within the pattern, respectively. The
- pcre2_get_error_message() function provides a textual message for each
+ (number of code units) within the pattern, respectively. The
+ pcre2_get_error_message() function provides a textual message for each
error code. Compilation errors are positive numbers, but UTF formatting
errors are negative numbers. For an invalid UTF-8 or UTF-16 string, the
offset is that of the first code unit of the failing character.
- Some errors are not detected until the whole pattern has been scanned;
- in these cases, the offset passed back is the length of the pattern.
- Note that the offset is in code units, not characters, even in a UTF
+ Some errors are not detected until the whole pattern has been scanned;
+ in these cases, the offset passed back is the length of the pattern.
+ Note that the offset is in code units, not characters, even in a UTF
mode. It may sometimes point into the middle of a UTF-8 or UTF-16 char-
acter.
- This code fragment shows a typical straightforward call to pcre2_com-
+ This code fragment shows a typical straightforward call to pcre2_com-
pile():
pcre2_code *re;
@@ -1030,158 +1028,158 @@
&erroffset, /* for error offset */
NULL); /* no compile context */
- The following names for option bits are defined in the pcre2.h header
+ The following names for option bits are defined in the pcre2.h header
file:
PCRE2_ANCHORED
If this bit is set, the pattern is forced to be "anchored", that is, it
- is constrained to match only at the first matching point in the string
- that is being searched (the "subject string"). This effect can also be
- achieved by appropriate constructs in the pattern itself, which is the
+ is constrained to match only at the first matching point in the string
+ that is being searched (the "subject string"). This effect can also be
+ achieved by appropriate constructs in the pattern itself, which is the
only way to do it in Perl.
PCRE2_ALLOW_EMPTY_CLASS
- By default, for compatibility with Perl, a closing square bracket that
- immediately follows an opening one is treated as a data character for
- the class. When PCRE2_ALLOW_EMPTY_CLASS is set, it terminates the
+ By default, for compatibility with Perl, a closing square bracket that
+ immediately follows an opening one is treated as a data character for
+ the class. When PCRE2_ALLOW_EMPTY_CLASS is set, it terminates the
class, which therefore contains no characters and so can never match.
PCRE2_ALT_BSUX
- This option request alternative handling of three escape sequences,
- which makes PCRE2's behaviour more like ECMAscript (aka JavaScript).
+ This option request alternative handling of three escape sequences,
+ which makes PCRE2's behaviour more like ECMAscript (aka JavaScript).
When it is set:
(1) \U matches an upper case "U" character; by default \U causes a com-
pile time error (Perl uses \U to upper case subsequent characters).
(2) \u matches a lower case "u" character unless it is followed by four
- hexadecimal digits, in which case the hexadecimal number defines the
- code point to match. By default, \u causes a compile time error (Perl
+ hexadecimal digits, in which case the hexadecimal number defines the
+ code point to match. By default, \u causes a compile time error (Perl
uses it to upper case the following character).
- (3) \x matches a lower case "x" character unless it is followed by two
- hexadecimal digits, in which case the hexadecimal number defines the
- code point to match. By default, as in Perl, a hexadecimal number is
+ (3) \x matches a lower case "x" character unless it is followed by two
+ hexadecimal digits, in which case the hexadecimal number defines the
+ code point to match. By default, as in Perl, a hexadecimal number is
always expected after \x, but it may have zero, one, or two digits (so,
for example, \xz matches a binary zero character followed by z).
PCRE2_AUTO_CALLOUT
- If this bit is set, pcre2_compile() automatically inserts callout
+ If this bit is set, pcre2_compile() automatically inserts callout
items, all with number 255, before each pattern item. For discussion of
the callout facility, see the pcre2callout documentation.
PCRE2_CASELESS
- If this bit is set, letters in the pattern match both upper and lower
- case letters in the subject. It is equivalent to Perl's /i option, and
+ If this bit is set, letters in the pattern match both upper and lower
+ case letters in the subject. It is equivalent to Perl's /i option, and
it can be changed within a pattern by a (?i) option setting.
PCRE2_DOLLAR_ENDONLY
- If this bit is set, a dollar metacharacter in the pattern matches only
- at the end of the subject string. Without this option, a dollar also
- matches immediately before a newline at the end of the string (but not
- before any other newlines). The PCRE2_DOLLAR_ENDONLY option is ignored
- if PCRE2_MULTILINE is set. There is no equivalent to this option in
+ If this bit is set, a dollar metacharacter in the pattern matches only
+ at the end of the subject string. Without this option, a dollar also
+ matches immediately before a newline at the end of the string (but not
+ before any other newlines). The PCRE2_DOLLAR_ENDONLY option is ignored
+ if PCRE2_MULTILINE is set. There is no equivalent to this option in
Perl, and no way to set it within a pattern.
PCRE2_DOTALL
- If this bit is set, a dot metacharacter in the pattern matches any
- character, including one that indicates a newline. However, it only
+ If this bit is set, a dot metacharacter in the pattern matches any
+ character, including one that indicates a newline. However, it only
ever matches one character, even if newlines are coded as CRLF. Without
this option, a dot does not match when the current position in the sub-
- ject is at a newline. This option is equivalent to Perl's /s option,
+ ject is at a newline. This option is equivalent to Perl's /s option,
and it can be changed within a pattern by a (?s) option setting. A neg-
ative class such as [^a] always matches newline characters, independent
of the setting of this option.
PCRE2_DUPNAMES
- If this bit is set, names used to identify capturing subpatterns need
+ If this bit is set, names used to identify capturing subpatterns need
not be unique. This can be helpful for certain types of pattern when it
- is known that only one instance of the named subpattern can ever be
- matched. There are more details of named subpatterns below; see also
+ is known that only one instance of the named subpattern can ever be
+ matched. There are more details of named subpatterns below; see also
the pcre2pattern documentation.
PCRE2_EXTENDED
- If this bit is set, most white space characters in the pattern are
- totally ignored except when escaped or inside a character class. How-
- ever, white space is not allowed within sequences such as (?> that
+ If this bit is set, most white space characters in the pattern are
+ totally ignored except when escaped or inside a character class. How-
+ ever, white space is not allowed within sequences such as (?> that
introduce various parenthesized subpatterns, nor within numerical quan-
- tifiers such as {1,3}. Ignorable white space is permitted between an
- item and a following quantifier and between a quantifier and a follow-
+ tifiers such as {1,3}. Ignorable white space is permitted between an
+ item and a following quantifier and between a quantifier and a follow-
ing + that indicates possessiveness.
- PCRE2_EXTENDED also causes characters between an unescaped # outside a
- character class and the next newline, inclusive, to be ignored, which
+ PCRE2_EXTENDED also causes characters between an unescaped # outside a
+ character class and the next newline, inclusive, to be ignored, which
makes it possible to include comments inside complicated patterns. Note
- that the end of this type of comment is a literal newline sequence in
+ that the end of this type of comment is a literal newline sequence in
the pattern; escape sequences that happen to represent a newline do not
- count. PCRE2_EXTENDED is equivalent to Perl's /x option, and it can be
+ count. PCRE2_EXTENDED is equivalent to Perl's /x option, and it can be
changed within a pattern by a (?x) option setting.
Which characters are interpreted as newlines can be specified by a set-
- ting in the compile context that is passed to pcre2_compile() or by a
- special sequence at the start of the pattern, as described in the sec-
- tion entitled "Newline conventions" in the pcre2pattern documentation.
+ ting in the compile context that is passed to pcre2_compile() or by a
+ special sequence at the start of the pattern, as described in the sec-
+ tion entitled "Newline conventions" in the pcre2pattern documentation.
A default is defined when PCRE2 is built.
PCRE2_FIRSTLINE
- If this option is set, an unanchored pattern is required to match
- before or at the first newline in the subject string, though the
+ If this option is set, an unanchored pattern is required to match
+ before or at the first newline in the subject string, though the
matched text may continue over the newline.
PCRE2_MATCH_UNSET_BACKREF
- If this option is set, a back reference to an unset subpattern group
- matches an empty string (by default this causes the current matching
- alternative to fail). A pattern such as (\1)(a) succeeds when this
- option is set (assuming it can find an "a" in the subject), whereas it
- fails by default, for Perl compatibility. Setting this option makes
+ If this option is set, a back reference to an unset subpattern group
+ matches an empty string (by default this causes the current matching
+ alternative to fail). A pattern such as (\1)(a) succeeds when this
+ option is set (assuming it can find an "a" in the subject), whereas it
+ fails by default, for Perl compatibility. Setting this option makes
PCRE2 behave more like ECMAscript (aka JavaScript).
PCRE2_MULTILINE
- By default, for the purposes of matching "start of line" and "end of
- line", PCRE2 treats the subject string as consisting of a single line
- of characters, even if it actually contains newlines. The "start of
- line" metacharacter (^) matches only at the start of the string, and
- the "end of line" metacharacter ($) matches only at the end of the
+ By default, for the purposes of matching "start of line" and "end of
+ line", PCRE2 treats the subject string as consisting of a single line
+ of characters, even if it actually contains newlines. The "start of
+ line" metacharacter (^) matches only at the start of the string, and
+ the "end of line" metacharacter ($) matches only at the end of the
string, or before a terminating newline (except when PCRE2_DOL-
- LAR_ENDONLY is set). Note, however, that unless PCRE2_DOTALL is set,
+ LAR_ENDONLY is set). Note, however, that unless PCRE2_DOTALL is set,
the "any character" metacharacter (.) does not match at a newline. This
behaviour (for ^, $, and dot) is the same as Perl.
- When PCRE2_MULTILINE it is set, the "start of line" and "end of line"
- constructs match immediately following or immediately before internal
- newlines in the subject string, respectively, as well as at the very
- start and end. This is equivalent to Perl's /m option, and it can be
+ When PCRE2_MULTILINE it is set, the "start of line" and "end of line"
+ constructs match immediately following or immediately before internal
+ newlines in the subject string, respectively, as well as at the very
+ start and end. This is equivalent to Perl's /m option, and it can be
changed within a pattern by a (?m) option setting. If there are no new-
- lines in a subject string, or no occurrences of ^ or $ in a pattern,
+ lines in a subject string, or no occurrences of ^ or $ in a pattern,
setting PCRE2_MULTILINE has no effect.
PCRE2_NEVER_UCP
- This option locks out the use of Unicode properties for handling \B,
+ This option locks out the use of Unicode properties for handling \B,
\b, \D, \d, \S, \s, \W, \w, and some of the POSIX character classes, as
- described for the PCRE2_UCP option below. In particular, it prevents
- the creator of the pattern from enabling this facility by starting the
- pattern with (*UCP). This may be useful in applications that process
- patterns from external sources. The option combination PCRE_UCP and
+ described for the PCRE2_UCP option below. In particular, it prevents
+ the creator of the pattern from enabling this facility by starting the
+ pattern with (*UCP). This may be useful in applications that process
+ patterns from external sources. The option combination PCRE_UCP and
PCRE_NEVER_UCP causes an error.
PCRE2_NEVER_UTF
- This option locks out interpretation of the pattern as UTF-8, UTF-16,
+ This option locks out interpretation of the pattern as UTF-8, UTF-16,
or UTF-32, depending on which library is in use. In particular, it pre-
- vents the creator of the pattern from switching to UTF interpretation
+ vents 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
PCRE2_UTF and PCRE2_NEVER_UTF causes an error.
@@ -1189,98 +1187,99 @@
PCRE2_NO_AUTO_CAPTURE
If this option is set, it disables the use of numbered capturing paren-
- theses in the pattern. Any opening parenthesis that is not followed by
- ? behaves as if it were followed by ?: but named parentheses can still
- be used for capturing (and they acquire numbers in the usual way).
+ theses in the pattern. Any opening parenthesis that is not followed by
+ ? behaves as if it were followed by ?: but named parentheses can still
+ be used for capturing (and they acquire numbers in the usual way).
There is no equivalent of this option in Perl.
PCRE2_NO_AUTO_POSSESS
If this option is set, it disables "auto-possessification", which 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 callouts are never
+ 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 callouts 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
+ a full unoptimized search and run all the callouts, but it is mainly
provided for testing purposes.
PCRE2_NO_START_OPTIMIZE
- This is an option whose main effect is at matching time. It does not
+ This is an option whose main effect is at matching time. It does not
change what pcre2_compile() generates, but it does affect the output of
the JIT compiler.
- There are a number of optimizations that may occur at the start of a
- match, in order to speed up the process. For example, if it is known
- that an unanchored match must start with a specific character, the
- matching code searches the subject for that character, and fails imme-
- diately if it cannot find it, without actually running the main match-
- ing function. This means that a special item such as (*COMMIT) at the
- start of a pattern is not considered until after a suitable starting
- point for the match has been found. Also, when callouts or (*MARK)
- items are in use, these "start-up" optimizations can cause them to be
- skipped if the pattern is never actually used. The start-up optimiza-
- tions are in effect a pre-scan of the subject that takes place before
+ There are a number of optimizations that may occur at the start of a
+ match, in order to speed up the process. For example, if it is known
+ that an unanchored match must start with a specific character, the
+ matching code searches the subject for that character, and fails imme-
+ diately if it cannot find it, without actually running the main match-
+ ing function. This means that a special item such as (*COMMIT) at the
+ start of a pattern is not considered until after a suitable starting
+ point for the match has been found. Also, when callouts or (*MARK)
+ items are in use, these "start-up" optimizations can cause them to be
+ skipped if the pattern is never actually used. The start-up optimiza-
+ tions are in effect a pre-scan of the subject that takes place before
the pattern is run.
The PCRE2_NO_START_OPTIMIZE option disables the start-up optimizations,
- possibly causing performance to suffer, but ensuring that in cases
- where the result is "no match", the callouts do occur, and that items
+ possibly causing performance to suffer, but ensuring that in cases
+ where the result is "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.
- Setting PCRE2_NO_START_OPTIMIZE may change the outcome of a matching
+ Setting PCRE2_NO_START_OPTIMIZE may change the outcome of a matching
operation. Consider the pattern
(*COMMIT)ABC
- When this is compiled, PCRE2 records the fact that a match must start
- with the character "A". Suppose the subject string is "DEFABC". The
- start-up optimization scans along the subject, finds "A" and runs the
- first match attempt from there. The (*COMMIT) item means that the pat-
- tern must match the current starting position, which in this case, it
- does. However, if the same match is run with PCRE2_NO_START_OPTIMIZE
- set, the initial scan along the subject string does not happen. The
- first match attempt is run starting from "D" and when this fails,
- (*COMMIT) prevents any further matches being tried, so the overall
+ When this is compiled, PCRE2 records the fact that a match must start
+ with the character "A". Suppose the subject string is "DEFABC". The
+ start-up optimization scans along the subject, finds "A" and runs the
+ first match attempt from there. The (*COMMIT) item means that the pat-
+ tern must match the current starting position, which in this case, it
+ does. However, if the same match is run with PCRE2_NO_START_OPTIMIZE
+ set, the initial scan along the subject string does not happen. The
+ first match attempt is run starting from "D" and when this fails,
+ (*COMMIT) prevents any further matches being tried, so the overall
result is "no match". There are also other start-up optimizations. For
example, a minimum length for the subject may be recorded. Consider the
pattern
(*MARK:A)(X|Y)
- The minimum length for a match is one character. If the subject is
+ The minimum length for a match is one character. If the subject is
"ABC", there will be attempts to match "ABC", "BC", and "C". An attempt
to match an empty string at the end of the subject does not take place,
- because PCRE2 knows that the subject is now too short, and so the
- (*MARK) is never encountered. In this case, the optimization does not
+ because PCRE2 knows that the subject is now too short, and so the
+ (*MARK) is never encountered. In this case, the optimization does not
affect the overall match result, which is still "no match", but it does
affect the auxiliary information that is returned.
PCRE2_NO_UTF_CHECK
- When PCRE2_UTF is set, the validity of the pattern as a UTF string is
- automatically checked. There are discussions about the validity of
- UTF-8 strings, UTF-16 strings, and UTF-32 strings in the pcre2unicode
+ When PCRE2_UTF is set, the validity of the pattern as a UTF string is
+ automatically checked. There are discussions about the validity of
+ UTF-8 strings, UTF-16 strings, and UTF-32 strings in the pcre2unicode
document. If an invalid UTF sequence is found, pcre2_compile() returns
a negative error code.
If you know that your pattern is valid, and you want to skip this check
- for performance reasons, you can set the PCRE2_NO_UTF_CHECK option.
- When it is set, the effect of passing an invalid UTF string as a pat-
- tern is undefined. It may cause your program to crash or loop. Note
- that this option can also be passed to pcre2_match() and
+ for performance reasons, you can set the PCRE2_NO_UTF_CHECK option.
+ When it is set, the effect of passing an invalid UTF string as a pat-
+ tern is undefined. It may cause your program to crash or loop. Note
+ that this option can also be passed to pcre2_match() and
pcre_dfa_match(), to suppress validity checking of the subject string.
PCRE2_UCP
This option changes the way PCRE2 processes \B, \b, \D, \d, \S, \s, \W,
- \w, and some of the POSIX character classes. By default, only ASCII
- characters are recognized, but if PCRE2_UCP is set, Unicode properties
- are used instead to classify characters. More details are given in the
+ \w, and some of the POSIX character classes. By default, only ASCII
+ characters are recognized, but if PCRE2_UCP is set, Unicode properties
+ are used instead to classify characters. More details are given in the
section on generic character types in the pcre2pattern page. If you set
- PCRE2_UCP, matching one of the items it affects takes much longer. The
- option is available only if PCRE2 has been compiled with UTF support.
+ PCRE2_UCP, matching one of the items it affects takes much longer. The
+ option is available only if PCRE2 has been compiled with Unicode sup-
+ port.
PCRE2_UNGREEDY
@@ -1293,18 +1292,19 @@
This option causes PCRE2 to regard both the pattern and the subject
strings that are subsequently processed as strings of UTF characters
- instead of single-code-unit strings. However, it is available only when
- PCRE2 is built to include UTF support. If not, the use of this option
- provokes an error. Details of how this option changes the behaviour of
- PCRE2 are given in the pcre2unicode page.
+ instead of single-code-unit strings. It is available when PCRE2 is
+ built to include Unicode support (which is the default). If Unicode
+ support is not available, the use of this option provokes an error.
+ Details of how this option changes the behaviour of PCRE2 are given in
+ the pcre2unicode page.
COMPILATION ERROR CODES
- There are over 80 positive error codes that pcre2_compile() may return
+ There are over 80 positive error codes that pcre2_compile() may return
if it finds an error in the pattern. There are also some negative error
- codes that are used for invalid UTF strings. These are the same as
- given by pcre2_match() and pcre2_dfa_match(), and are described in the
+ codes that are used for invalid UTF strings. These are the same as
+ given by pcre2_match() and pcre2_dfa_match(), and are described in the
pcre2unicode page. The pcre2_get_error_message() function can be called
to obtain a textual error message from any error code.
@@ -1328,31 +1328,30 @@
void pcre2_jit_stack_free(pcre2_jit_stack *jit_stack);
- These functions provide support for JIT compilation, which, if the
- just-in-time compiler is available, further processes a compiled pat-
+ These functions provide support for JIT compilation, which, if the
+ just-in-time compiler is available, further processes a compiled pat-
tern into machine code that executes much faster than the pcre2_match()
- interpretive matching function. Full details are given in the pcre2jit
+ interpretive matching function. Full details are given in the pcre2jit
documentation.
- JIT compilation is a heavyweight optimization. It can take some time
- for patterns to be analyzed, and for one-off matches and simple pat-
- terns the benefit of faster execution might be offset by a much slower
- compilation time. Most, but not all patterns can be optimized by the
+ JIT compilation is a heavyweight optimization. It can take some time
+ for patterns to be analyzed, and for one-off matches and simple pat-
+ terns the benefit of faster execution might be offset by a much slower
+ compilation time. Most, but not all patterns can be optimized by the
JIT compiler.
LOCALE SUPPORT
- PCRE2 handles caseless matching, and determines whether characters are
- letters, digits, or whatever, by reference to a set of tables, indexed
- by character code point. When running in UTF-8 mode, or using the
- 16-bit or 32-bit libraries, this applies only to characters with code
- points less than 256. By default, higher-valued code points never match
- escapes such as \w or \d. However, if PCRE2 is built with UTF support,
- all characters can be tested with \p and \P, or, alternatively, the
- PCRE2_UCP option can be set when a pattern is compiled; this causes \w
- and friends to use Unicode property support instead of the built-in
- tables.
+ PCRE2 handles caseless matching, and determines whether characters are
+ letters, digits, or whatever, by reference to a set of tables, indexed
+ by character code point. This applies only to characters whose code
+ points are less than 256. By default, higher-valued code points never
+ match escapes such as \w or \d. However, if PCRE2 is built with UTF
+ support, all characters can be tested with \p and \P, or, alterna-
+ tively, the PCRE2_UCP option can be set when a pattern is compiled;
+ this causes \w and friends to use Unicode property support instead of
+ the built-in tables.
The use of locales with Unicode is discouraged. If you are handling
characters with code points greater than 128, you should either use
@@ -1463,31 +1462,30 @@
PCRE2_INFO_BSR
The output is a uint32_t whose value indicates what character sequences
- the \R escape sequence matches by default. A value of 0 means that \R
- matches any Unicode line ending sequence; a value of 1 means that \R
- matches only CR, LF, or CRLF. The default can be overridden when a pat-
- tern is matched.
+ the \R escape sequence matches. A value of PCRE2_BSR_UNICODE means that
+ \R matches any Unicode line ending sequence; a value of PCRE2_BSR_ANY-
+ CRLF means that \R matches only CR, LF, or CRLF.
PCRE2_INFO_CAPTURECOUNT
- Return the number of capturing subpatterns in the pattern. The third
+ Return the number of capturing subpatterns in the pattern. The third
argument should point to an uint32_t variable.
PCRE2_INFO_FIRSTCODETYPE
Return information about the first code unit of any matched string, for
- a non-anchored pattern. The third argument should point to an uint32_t
+ a non-anchored pattern. The third argument should point to an uint32_t
variable.
- If there is a fixed first value, for example, the letter "c" from a
- pattern such as (cat|cow|coyote), 1 is returned, and the character
- value can be retrieved using PCRE2_INFO_FIRSTCODEUNIT. If there is no
+ If there is a fixed first value, for example, the letter "c" from a
+ pattern such as (cat|cow|coyote), 1 is returned, and the character
+ value can be retrieved using PCRE2_INFO_FIRSTCODEUNIT. If there is no
fixed first value, and if either
(a) the pattern was compiled with the PCRE2_MULTILINE option, and every
branch starts with "^", or
- (b) every branch of the pattern starts with ".*" and PCRE2_DOTALL is
+ (b) every branch of the pattern starts with ".*" and PCRE2_DOTALL is
not set (if it were set, the pattern would be anchored),
2 is returned, indicating that the pattern matches only at the start of
@@ -1496,99 +1494,99 @@
PCRE2_INFO_FIRSTCODEUNIT
- Return the value of the first code unit of any matched string in the
+ Return the value of the first code unit of any matched string in the
situation where PCRE2_INFO_FIRSTCODETYPE returns 1; otherwise return 0.
- The third argument should point to an uint32_t variable. 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 in UTF-32 mode the
+ The third argument should point to an uint32_t variable. 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 in UTF-32 mode the
value can be up to 0x10ffff, and up to 0xffffffff when not using UTF-32
mode.
PCRE2_INFO_FIRSTBITMAP
- In the absence of a single first code unit for a non-anchored pattern,
- pcre2_compile() may construct a 256-bit table that defines a fixed set
- of values for the first code unit in any match. For example, a pattern
- that starts with [abc] results in a table with three bits set. When
- code unit values greater than 255 are supported, the flag bit for 255
- means "any code unit of value 255 or above". If such a table was con-
- structed, a pointer to it is returned. Otherwise NULL is returned. The
+ In the absence of a single first code unit for a non-anchored pattern,
+ pcre2_compile() may construct a 256-bit table that defines a fixed set
+ of values for the first code unit in any match. For example, a pattern
+ that starts with [abc] results in a table with three bits set. When
+ code unit values greater than 255 are supported, the flag bit for 255
+ means "any code unit of value 255 or above". If such a table was con-
+ structed, a pointer to it is returned. Otherwise NULL is returned. The
third argument should point to an const uint8_t * variable.
PCRE2_INFO_HASCRORLF
- Return 1 if the pattern contains any explicit matches for CR or LF
+ Return 1 if the pattern contains any explicit matches for CR or LF
characters, otherwise 0. The third argument should point to an uint32_t
- variable. An explicit match is either a literal CR or LF character, or
+ variable. An explicit match is either a literal CR or LF character, or
\r or \n.
PCRE2_INFO_JCHANGED
- Return 1 if the (?J) or (?-J) option setting is used in the pattern,
- otherwise 0. The third argument should point to an uint32_t variable.
- (?J) and (?-J) set and unset the local PCRE2_DUPNAMES option, respec-
+ Return 1 if the (?J) or (?-J) option setting is used in the pattern,
+ otherwise 0. The third argument should point to an uint32_t variable.
+ (?J) and (?-J) set and unset the local PCRE2_DUPNAMES option, respec-
tively.
PCRE2_INFO_JITSIZE
- If the compiled pattern was successfully processed by pcre2_jit_com-
- pile(), return the size of the JIT compiled code, otherwise return
+ If the compiled pattern was successfully processed by pcre2_jit_com-
+ pile(), return the size of the JIT compiled code, otherwise return
zero. The third argument should point to a size_t variable.
PCRE2_INFO_LASTCODETYPE
- Returns 1 if there is a rightmost literal code unit that must exist in
- any matched string, other than at its start. The third argument should
- point to an uint32_t variable. If there is no such value, 0 is
- returned. When 1 is returned, the code unit value itself can be
+ Returns 1 if there is a rightmost literal code unit that must exist in
+ any matched string, other than at its start. The third argument should
+ point to an uint32_t variable. If there is no such value, 0 is
+ returned. When 1 is returned, the code unit value itself can be
retrieved using PCRE2_INFO_LASTCODEUNIT.
For anchored patterns, a last literal value is recorded only if it fol-
- lows something of variable length. For example, for the pattern
- /^a\d+z\d+/ the returned value is 1 (with "z" returned from
+ lows something of variable length. For example, for the pattern
+ /^a\d+z\d+/ the returned value is 1 (with "z" returned from
PCRE2_INFO_LASTCODEUNIT), but for /^a\dz\d/ the returned value is 0.
PCRE2_INFO_LASTCODEUNIT
- 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 third argument should point to an uint32_t variable. If
+ 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 third argument should point to an uint32_t variable. If
there is no such value, 0 is returned.
PCRE2_INFO_MATCHEMPTY
- Return 1 if the pattern can match an empty string, otherwise 0. The
+ Return 1 if the pattern can match an empty string, otherwise 0. The
third argument should point to an uint32_t variable.
PCRE2_INFO_MATCHLIMIT
- 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 third
- argument should point to an unsigned 32-bit integer. If no such value
- has been set, the call to pcre2_pattern_info() returns the error
+ 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 third
+ argument should point to an unsigned 32-bit integer. If no such value
+ has been set, the call to pcre2_pattern_info() returns the error
PCRE2_ERROR_UNSET.
PCRE2_INFO_MAXLOOKBEHIND
Return the number of characters (not code units) in the longest lookbe-
- hind assertion in the pattern. The third argument should point to an
- unsigned 32-bit integer. This information is useful when doing multi-
- segment matching using the partial matching facilities. Note that the
+ hind assertion in the pattern. The third argument should point to an
+ unsigned 32-bit integer. 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 pro-
+ 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 pro-
cessed. Otherwise, if there are no lookbehinds in the pattern, \A might
match incorrectly at the start of a new segment.
PCRE2_INFO_MINLENGTH
- If a minimum length for matching subject strings was computed, its
- value is returned. Otherwise the returned value is 0. The value is a
- number of characters, which in UTF mode may be different from the num-
- ber of code units. The third argument should point to an uint32_t
- variable. The value is a lower bound to the length of any matching
- string. There may not be any strings of that length that do actually
+ If a minimum length for matching subject strings was computed, its
+ value is returned. Otherwise the returned value is 0. The value is a
+ number of characters, which in UTF mode may be different from the num-
+ ber of code units. The third argument should point to an uint32_t
+ variable. The value is a lower bound to the length of any matching
+ string. There may not be any strings of that length that do actually
match, but every string that does match is at least that long.
PCRE2_INFO_NAMECOUNT
@@ -1596,26 +1594,27 @@
PCRE2_INFO_NAMETABLE
PCRE2 supports the use of named as well as numbered capturing parenthe-
- ses. The names are just an additional way of identifying the parenthe-
+ ses. The names are just an additional way of identifying the parenthe-
ses, which still acquire numbers. Several convenience functions such as
- pcre2_substring_get_byname() are provided for extracting captured sub-
- strings by name. It is also possible to extract the data directly, by
- first converting the name to a number in order to access the correct
- pointers in the output vector (described with pcre2_match() below). To
- do the conversion, you need to use the name-to-number map, which is
+ pcre2_substring_get_byname() are provided for extracting captured sub-
+ strings by name. It is also possible to extract the data directly, by
+ first converting the name to a number in order to access the correct
+ pointers in the output vector (described with pcre2_match() below). To
+ do the conversion, you need to use the name-to-number map, which is
described by these three values.
- The map consists of a number of fixed-size entries. PCRE2_INFO_NAME-
- COUNT gives the number of entries, and PCRE2_INFO_NAMEENTRYSIZE gives
- the size of each entry; both of these return a uint32_t value. The
- entry size depends on the length of the longest name.
+ The map consists of a number of fixed-size entries. PCRE2_INFO_NAME-
+ COUNT gives the number of entries, and PCRE2_INFO_NAMEENTRYSIZE gives
+ the size of each entry in code units; both of these return a uint32_t
+ value. The entry size depends on the length of the longest name.
+
PCRE2_INFO_NAMETABLE returns a pointer to the first entry of the table.
This is a PCRE2_SPTR pointer to a block of code units. In the 8-bit
library, the first two bytes of each entry are the number of the cap-
turing parenthesis, most significant byte first. In the 16-bit library,
- the pointer points to 16-bit data units, the first of which contains
+ the pointer points to 16-bit code 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.
+ 32-bit code units, the first of which contains the parenthesis number.
The rest of the entry is the corresponding name, zero terminated.
The names are in alphabetical order. If (?| is used to create multiple
@@ -1653,35 +1652,34 @@
PCRE2_INFO_NEWLINE
- The output is a uint32_t whose value specifies the default character
- sequence that will be recognized as meaning "newline" while matching.
- The values are:
+ The output is a uint32_t with one of the following values:
- 1 Carriage return (CR)
- 2 Linefeed (LF)
- 3 Carriage return, linefeed (CRLF)
- 4 Any Unicode line ending
- 5 Any of CR, LF, or CRLF
+ PCRE2_NEWLINE_CR Carriage return (CR)
+ PCRE2_NEWLINE_LF Linefeed (LF)
+ PCRE2_NEWLINE_CRLF Carriage return, linefeed (CRLF)
+ PCRE2_NEWLINE_ANY Any Unicode line ending
+ PCRE2_NEWLINE_ANYCRLF Any of CR, LF, or CRLF
- The default can be overridden when a pattern is matched.
+ This specifies the default character sequence that will be recognized
+ as meaning "newline" while matching.
PCRE2_INFO_RECURSIONLIMIT
- 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 third
- argument should point to an unsigned 32-bit integer. If no such value
- has been set, the call to pcre2_pattern_info() returns the error
+ 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 third
+ argument should point to an unsigned 32-bit integer. If no such value
+ has been set, the call to pcre2_pattern_info() returns the error
PCRE2_ERROR_UNSET.
PCRE2_INFO_SIZE
- Return the size of the compiled pattern in bytes (for all three
- libraries). The third argument should point to a size_t variable. This
- value does not include the size of the pcre2_code structure that is
+ Return the size of the compiled pattern in bytes (for all three
+ libraries). The third argument should point to a size_t variable. This
+ value does not include the size of the pcre2_code structure that is
returned by pcre_compile(). The value that is used when pcre2_compile()
- is getting memory in which to place the compiled data is the value
+ is getting memory in which to place the compiled data is the value
returned by this option plus the size of the pcre2_code structure. Pro-
- cessing a pattern with the JIT compiler does not alter the value
+ cessing a pattern with the JIT compiler does not alter the value
returned by this option.
@@ -1695,39 +1693,40 @@
void pcre2_match_data_free(pcre2_match_data *match_data);
- Information about successful and unsuccessful matches is placed in a
- match data block, which is an opaque structure that is accessed by
- function calls. In particular, the match data block contains a vector
- of offsets into the subject string that define the matched part of the
- subject and any substrings that were capured. This is know as the ovec-
- tor.
+ Information about successful and unsuccessful matches is placed in a
+ match data block, which is an opaque structure that is accessed by
+ function calls. In particular, the match data block contains a vector
+ of offsets into the subject string that define the matched part of the
+ subject and any substrings that were captured. This is know as the
+ ovector.
- Before calling pcre2_match() or pcre2_dfa_match() you must create a
- match data block by calling one of the creation functions above. For
- pcre2_match_data_create(), the first argument is the number of pairs of
- offsets in the ovector. One pair of offsets is required to identify the
- string that matched the whole pattern, with another pair for each cap-
- tured substring. For example, a value of 4 creates enough space to
- record the matched portion of the subject plus three captured sub-
- strings. A minimum of at least 1 pair is imposed by
+ Before calling pcre2_match(), pcre2_dfa_match(), or pcre2_jit_match()
+ you must create a match data block by calling one of the creation func-
+ tions above. For pcre2_match_data_create(), the first argument is the
+ number of pairs of offsets in the ovector. One pair of offsets is
+ required to identify the string that matched the whole pattern, with
+ another pair for each captured substring. For example, a value of 4
+ creates enough space to record the matched portion of the subject plus
+ three captured substrings. A minimum of at least 1 pair is imposed by
pcre2_match_data_create(), so it is always possible to return the over-
all matched string.
- For pcre2_match_data_create_from_pattern(), the first argument is a
- pointer to a compiled pattern. In this case the ovector is created to
- be exactly the right size to hold all the substrings a pattern might
+ For pcre2_match_data_create_from_pattern(), the first argument is a
+ pointer to a compiled pattern. In this case the ovector is created to
+ be exactly the right size to hold all the substrings a pattern might
capture.
- The second argument of both these functions ia a pointer to a general
- context, which can specify custom memory management for obtaining the
- memory for the match data block. If you are not using custom memory
+ The second argument of both these functions is a pointer to a general
+ context, which can specify custom memory management for obtaining the
+ memory for the match data block. If you are not using custom memory
management, pass NULL.
- A match data block can be used many times, with the same or different
- compiled patterns. When it is no longer needed, it should be freed by
- calling pcre2_match_data_free(). How to extract information from a
- match data block after a match operation is described in the sections
- on matched strings and other match data below.
+ A match data block can be used many times, with the same or different
+ compiled patterns. When it is no longer needed, it should be freed by
+ calling pcre2_match_data_free(). You can extract information from a
+ match data block after a match operation has finished, using functions
+ that are described in the sections on matched strings and other match
+ data below.
MATCHING A PATTERN: THE TRADITIONAL FUNCTION
@@ -1826,12 +1825,10 @@
PCRE2_NO_UTF_CHECK, PCRE2_PARTIAL_HARD, and PCRE2_PARTIAL_SOFT. Their
action is described below.
- If the pattern was successfully processed by the just-in-time (JIT)
- compiler, the only supported options for matching using the JIT code
- are PCRE2_NOTBOL, PCRE2_NOTEOL, PCRE2_NOTEMPTY, PCRE2_NOTEMPTY_ATSTART,
- PCRE2_NO_UTF_CHECK, PCRE2_PARTIAL_HARD, and PCRE2_PARTIAL_SOFT. If an
- unsupported option is used, JIT matching is disabled and the normal
- interpretive code in pcre2_match() is run.
+ Setting PCRE2_ANCHORED at match time is not supported by the just-in-
+ time (JIT) compiler. If it is set, JIT matching is disabled and the
+ normal interpretive code in pcre2_match() is run. The remaining options
+ are supported for JIT matching.
PCRE2_ANCHORED
@@ -1845,18 +1842,18 @@
This option specifies that first character of the subject string is not
the beginning of a line, so the circumflex metacharacter should not
- match before it. Setting this without PCRE2_MULTILINE (at compile time)
- causes circumflex never to match. This option affects only the behav-
- iour of the circumflex metacharacter. It does not affect \A.
+ match before it. Setting this without having set PCRE2_MULTILINE at
+ compile time causes circumflex never to match. This option affects only
+ the behaviour of the circumflex metacharacter. It does not affect \A.
PCRE2_NOTEOL
This option specifies that the end of the subject string is not the end
of a line, so the dollar metacharacter should not match it nor (except
in multiline mode) a newline immediately before it. Setting this with-
- out PCRE2_MULTILINE (at compile time) causes dollar never to match.
- This option affects only the behaviour of the dollar metacharacter. It
- does not affect \Z or \z.
+ out having set PCRE2_MULTILINE at compile time causes dollar never to
+ match. This option affects only the behaviour of the dollar metacharac-
+ ter. It does not affect \Z or \z.
PCRE2_NOTEMPTY
@@ -1869,14 +1866,16 @@
is applied to a string not beginning with "a" or "b", it matches an
empty string at the start of the subject. With PCRE2_NOTEMPTY set, this
- match is not valid, so PCRE2 searches further into the string for
- occurrences of "a" or "b".
+ match is not valid, so pcre2_match() searches further into the string
+ for occurrences of "a" or "b".
PCRE2_NOTEMPTY_ATSTART
- This is like PCRE2_NOTEMPTY, except that an empty string match that is
- not at the start of the subject is permitted. If the pattern is
- anchored, such a match can occur only if the pattern contains \K.
+ This is like PCRE2_NOTEMPTY, except that it locks out an empty string
+ match only at the first matching position, that is, at the start of the
+ subject plus the starting offset. An empty string match later in the
+ subject is permitted. If the pattern is anchored, such a match can
+ occur only if the pattern contains \K.
PCRE2_NO_UTF_CHECK
@@ -1910,9 +1909,9 @@
happens when PCRE2_PARTIAL_SOFT (but not PCRE2_PARTIAL_HARD) is set,
matching continues by testing any remaining alternatives. Only if no
complete match can be found is PCRE2_ERROR_PARTIAL returned instead of
- PCRE2_ERROR_NOMATCH. In other words, PCRE2_PARTIAL_SOFT says that the
- caller is prepared to handle a partial match, but only if no complete
- match can be found.
+ PCRE2_ERROR_NOMATCH. In other words, PCRE2_PARTIAL_SOFT specifies that
+ the caller is prepared to handle a partial match, but only if no com-
+ plete match can be found.
If PCRE2_PARTIAL_HARD is set, it overrides PCRE2_PARTIAL_SOFT. In this
case, if a partial match is found, pcre2_match() immediately returns
@@ -1930,15 +1929,15 @@
ally the standard convention for the operating system. The default can
be overridden in a compile context. During matching, the newline
choice affects the behaviour of the dot, circumflex, and dollar
- metacharacters. It may also alter the way the match position is
- advanced after a match failure for an unanchored pattern.
+ metacharacters. It may also alter the way the match starting position
+ is advanced after a match failure for an unanchored pattern.
When PCRE2_NEWLINE_CRLF, PCRE2_NEWLINE_ANYCRLF, or PCRE2_NEWLINE_ANY is
- set, and a match attempt for an unanchored pattern fails when the cur-
- rent position is at a CRLF sequence, and the pattern contains no
- explicit matches for CR or LF characters, the match position is
- advanced by two characters instead of one, in other words, to after the
- CRLF.
+ set as the newline convention, and a match attempt for an unanchored
+ pattern fails when the current starting position is at a CRLF sequence,
+ and the pattern contains no explicit matches for CR or LF characters,
+ the match position is advanced by two characters instead of one, in
+ other words, to after the CRLF.
The above rule is a compromise that makes the most common cases work as
expected. For example, if the pattern is .+A (and the PCRE2_DOTALL
@@ -1950,8 +1949,8 @@
An explicit match for CR of LF is either a literal appearance of one of
those characters in the pattern, or one of the \r or \n escape
- sequences. Implicit matches such as [^X] do not count, nor does \s
- (which includes CR and LF in the characters that it matches).
+ sequences. Implicit matches such as [^X] do not count, nor does \s,
+ even though it includes CR and LF in the characters that it matches.
Notwithstanding the above, anomalous effects may still occur when CRLF
is a valid newline sequence and explicit \r or \n escapes appear in the
@@ -1968,102 +1967,105 @@
addition, further substrings from the subject may be picked out by
parenthesized parts of the pattern. Following the usage in Jeffrey
Friedl's book, this is called "capturing" in what follows, and the
- phrase "capturing subpattern" is used for a fragment of a pattern that
- picks out a substring. PCRE2 supports several other kinds of parenthe-
- sized subpattern that do not cause substrings to be captured. The
- pcre2_pattern_info() function can be used to find out how many captur-
- ing subpatterns there are in a compiled pattern.
+ phrase "capturing subpattern" or "capturing group" is used for a frag-
+ ment of a pattern that picks out a substring. PCRE2 supports several
+ other kinds of parenthesized subpattern that do not cause substrings to
+ be captured. The pcre2_pattern_info() function can be used to find out
+ how many capturing subpatterns there are in a compiled pattern.
The overall matched string and any captured substrings are returned to
- the caller via a vector of PCRE2_SIZE values, called the ovector. This
- is contained within the match data block. You can obtain direct access
- to the ovector by calling pcre2_get_ovector_pointer() to find its
- address, and pcre2_get_ovector_count() to find the number of pairs of
- values it contains. Alternatively, you can use the auxiliary functions
- for accessing captured substrings by number or by name (see below).
+ the caller via a vector of PCRE2_SIZE values. This is called the ovec-
+ tor, and is contained within the match data block. You can obtain
+ direct access to the ovector by calling pcre2_get_ovector_pointer() to
+ find its address, and pcre2_get_ovector_count() to find the number of
+ pairs of values it contains. Alternatively, you can use the auxiliary
+ functions for accessing captured substrings by number or by name (see
+ below).
Within the ovector, the first in each pair of values is set to the off-
set of the first code unit of a substring, and the second is set to the
- offset of the first code unit after the end of a substring. These val-
- ues are always code unit offsets, not character offsets. That is, they
- are byte offsets in the 8-bit library, 16-bit offsets in the 16-bit
+ offset of the first code unit after the end of a substring. These val-
+ ues are always code unit offsets, not character offsets. That is, they
+ are byte offsets in the 8-bit library, 16-bit offsets in the 16-bit
library, and 32-bit offsets in the 32-bit library.
- The first pair of offsets (that is, ovector[0] and ovector[1]) identi-
- fies the portion of the subject string that was matched by the entire
- pattern. The next pair is used for the first capturing subpattern, and
- so on. The value returned by pcre2_match() is one more than the high-
- est numbered pair that has been set. For example, if two substrings
- have been captured, the returned value is 3. If there are no capturing
- subpatterns, the return value from a successful match is 1, indicating
+ The first pair of offsets (that is, ovector[0] and ovector[1]) identi-
+ fies the portion of the subject string that was matched by the entire
+ pattern. The next pair is used for the first capturing subpattern, and
+ so on. The value returned by pcre2_match() is one more than the high-
+ est numbered pair that has been set. For example, if two substrings
+ have been captured, the returned value is 3. If there are no capturing
+ subpatterns, the return value from a successful match is 1, indicating
that just the first pair of offsets has been set.
- If a capturing subpattern is matched repeatedly within a single match
+ If a capturing subpattern is matched repeatedly within a single match
operation, it is the last portion of the string that it matched that is
returned.
If the ovector is too small to hold all the captured substring offsets,
- as much as possible is filled in, and the function returns a value of
- zero. If captured substrings are not of interest, pcre2_match() may be
+ as much as possible is filled in, and the function returns a value of
+ zero. If captured substrings are not of interest, pcre2_match() may be
called with a match data block whose ovector is of minimum length (that
is, one pair). However, if the pattern contains back references and the
ovector is not big enough to remember the related substrings, PCRE2 has
- to get additional memory for use during matching. Thus it is usually
+ to get additional memory for use during matching. Thus it is usually
advisable to set up a match data block containing an ovector of reason-
able size.
- It is possible for capturing subpattern number n+1 to match some part
+ It is possible for capturing subpattern number n+1 to match some part
of the subject when subpattern n has not been used at all. For example,
- if the string "abc" is matched against the pattern (a|(z))(bc) the
+ if the string "abc" is matched against the pattern (a|(z))(bc) the
return from the function is 4, and subpatterns 1 and 3 are matched, but
- 2 is not. When this happens, both values in the offset pairs corre-
+ 2 is not. When this happens, both values in the offset pairs corre-
sponding to unused subpatterns are set to PCRE2_UNSET.
- Offset values that correspond to unused subpatterns at the end of the
- expression are also set to PCRE2_UNSET. For example, if the string
+ Offset values that correspond to unused subpatterns at the end of the
+ expression are also set to PCRE2_UNSET. For example, if the string
"abc" is matched against the pattern (abc)(x(yz)?)? subpatterns 2 and 3
- are not matched. The return from the function is 2, because the high-
+ are not matched. The return from the function is 2, because the high-
est used capturing subpattern number is 1. The offsets for for the sec-
- ond and third capturing subpatterns (assuming the vector is large
+ ond and third capturing subpatterns (assuming the vector is large
enough, of course) are set to PCRE2_UNSET.
Elements in the ovector that do not correspond to capturing parentheses
in the pattern are never changed. That is, if a pattern contains n cap-
turing parentheses, no more than ovector[0] to ovector[2n+1] are set by
- pcre2_match(). The other elements retain whatever values they previ-
+ pcre2_match(). The other elements retain whatever values they previ-
ously had.
- Other information about the match
+OTHER INFORMATION ABOUT A MATCH
+
PCRE2_SPTR pcre2_get_mark(pcre2_match_data *match_data);
PCRE2_SIZE pcre2_get_startchar(pcre2_match_data *match_data);
- In addition to the offsets in the ovector, other information about a
- match is retained in the match data block and can be retrieved by the
- above functions.
+ As well as the offsets in the ovector, other information about a match
+ is retained in the match data block and can be retrieved by the above
+ functions.
- When a (*MARK) name is to be passed back, pcre2_get_mark() returns a
- pointer to the zero-terminated name, which is within the compiled pat-
- tern. Otherwise NULL is returned. A (*MARK) name may be available
- after a failed match or a partial match, as well as after a successful
+ When a (*MARK) name is to be passed back, pcre2_get_mark() returns a
+ pointer to the zero-terminated name, which is within the compiled pat-
+ tern. Otherwise NULL is returned. A (*MARK) name may be available
+ after a failed match or a partial match, as well as after a successful
one.
- The code unit offset of the character at which a successful match
- started is returned by pcre2_get_startchar(). For a non-partial match,
- this can be different to the value of ovector[0] if the pattern con-
- tains the \K escape sequence. After a partial match, however, this
- value is always the same as ovector[0] because \K does not affect the
+ The code unit offset of the character at which a successful match
+ started is returned by pcre2_get_startchar(). For a non-partial match,
+ this can be different to the value of ovector[0] if the pattern con-
+ tains the \K escape sequence. After a partial match, however, this
+ value is always the same as ovector[0] because \K does not affect the
result of a partial match.
- Error return values from pcre2_match()
- If pcre2_match() fails, it returns a negative number. This can be con-
- verted to a text string by calling pcre2_get_error_message(). Negative
- error codes are also returned by other functions, and are documented
+ERROR RETURNS FROM pcre2_match()
+
+ If pcre2_match() fails, it returns a negative number. This can be con-
+ verted to a text string by calling pcre2_get_error_message(). Negative
+ error codes are also returned by other functions, and are documented
with them. The codes are given names in the header file. If UTF check-
ing is in force and an invalid UTF subject string is detected, one of a
- number of UTF-specific negative error codes is returned. Details are
+ number of UTF-specific negative error codes is returned. Details are
given in the pcre2unicode page. The following are the other errors that
may be returned by pcre2_match():
@@ -2073,24 +2075,24 @@
PCRE2_ERROR_PARTIAL
- The subject string did not match, but it did match partially. See the
+ The subject string did not match, but it did match partially. See the
pcre2partial documentation for details of partial matching.
PCRE2_ERROR_BADMAGIC
PCRE2 stores a 4-byte "magic number" at the start of the compiled code,
- to catch the case when it is passed a junk pointer. This is the error
+ to catch the case when it is passed a junk pointer. This is the error
that is returned when the magic number is not present.
PCRE2_ERROR_BADMODE
- This error is given when a pattern that was compiled by the 8-bit
- library is passed to a 16-bit or 32-bit library function, or vice
+ This error is given when a pattern that was compiled by the 8-bit
+ library is passed to a 16-bit or 32-bit library function, or vice
versa.
PCRE2_ERROR_BADOFFSET
- The value of startoffset greater than the length of the subject.
+ The value of startoffset was greater than the length of the subject.
PCRE2_ERROR_BADOPTION
@@ -2099,35 +2101,35 @@
PCRE2_ERROR_BADUTFOFFSET
The UTF code unit sequence that was passed as a subject was checked and
- found to be valid (the PCRE2_NO_UTF_CHECK option was not set), but the
- value of startoffset did not point to the beginning of a UTF character
+ found to be valid (the PCRE2_NO_UTF_CHECK option was not set), but the
+ value of startoffset did not point to the beginning of a UTF character
or the end of the subject.
PCRE2_ERROR_CALLOUT
- This error is never generated by pcre2_match() itself. It is provided
+ This error is never generated by pcre2_match() itself. It is provided
for use by callout functions that want to cause pcre2_match() to return
- a distinctive error code. See the pcre2callout documentation for
+ a distinctive error code. See the pcre2callout documentation for
details.
PCRE2_ERROR_INTERNAL
- An unexpected internal error has occurred. This error could be caused
+ An unexpected internal error has occurred. This error could be caused
by a bug in PCRE2 or by overwriting of the compiled pattern.
PCRE2_ERROR_JIT_BADOPTION
- This error is returned when a pattern that was successfully studied
- using JIT 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
+ This error is returned when a pattern that was successfully studied
+ using JIT 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 pcre2jit documentation for more details.
PCRE2_ERROR_JIT_STACKLIMIT
- This error is returned when a pattern that was successfully studied
- using JIT is being matched, but the memory available for the just-in-
- time processing stack is not large enough. See the pcre2jit documenta-
+ This error is returned when a pattern that was successfully studied
+ using JIT is being matched, but the memory available for the just-in-
+ time processing stack is not large enough. See the pcre2jit documenta-
tion for more details.
PCRE2_ERROR_MATCHLIMIT
@@ -2136,10 +2138,10 @@
PCRE2_ERROR_NOMEMORY
- If a pattern contains back references, but the ovector is not big
- enough to remember the referenced substrings, PCRE2 gets a block of
+ If a pattern contains back references, but the ovector is not big
+ enough to remember the referenced substrings, PCRE2 gets a block of
memory at the start of matching to use for this purpose. There are some
- other special cases where extra memory is needed during matching. This
+ other special cases where extra memory is needed during matching. This
error is given when memory cannot be obtained.
PCRE2_ERROR_NULL
@@ -2148,13 +2150,13 @@
PCRE2_ERROR_RECURSELOOP
- This error is returned when pcre2_match() detects a recursion loop
- within the pattern. Specifically, it means that either the whole pat-
+ This error is returned when pcre2_match() detects a recursion loop
+ within the pattern. Specifically, it means that either the whole pat-
tern or a subpattern has been called recursively for the second time at
- the same position in the subject string. Some simple patterns that
- might do this are detected and faulted at compile time, but more com-
- plicated cases, in particular mutual recursions between two different
- subpatterns, cannot be detected until run time.
+ the same position in the subject string. Some simple patterns that
+ might do this are detected and faulted at compile time, but more com-
+ plicated cases, in particular mutual recursions between two different
+ subpatterns, cannot be detected until matching is attempted.
PCRE2_ERROR_RECURSIONLIMIT
@@ -2176,52 +2178,52 @@
void pcre2_substring_free(PCRE2_UCHAR *buffer);
- Captured substrings can be accessed directly by using the ovector as
+ Captured substrings can be accessed directly by using the ovector as
described above. For convenience, auxiliary functions are provided for
- extracting captured substrings as new, separate, zero-terminated
- strings. The functions in this section identify substrings by number.
- The next section describes similar functions for extracting substrings
+ extracting captured substrings as new, separate, zero-terminated
+ strings. The functions in this section identify substrings by number.
+ The next section describes similar functions for extracting substrings
by name. A substring that contains a binary zero is correctly extracted
- and has a further zero added on the end, but the result is not, of
+ and has a further zero added on the end, but the result is not, of
course, a C string.
- You can find the length in code units of a captured substring without
- extracting it by calling pcre2_substring_length_bynumber(). The first
- argument is a pointer to the match data block, the second is the group
- number, and the third is a pointer to a variable into which the length
+ You can find the length in code units of a captured substring without
+ extracting it by calling pcre2_substring_length_bynumber(). The first
+ argument is a pointer to the match data block, the second is the group
+ number, and the third is a pointer to a variable into which the length
is placed.
- The pcre2_substring_copy_bynumber() function copies one string into a
- supplied buffer, whereas pcre2_substring_get_bynumber() copies it into
+ The pcre2_substring_copy_bynumber() function copies one string into a
+ supplied buffer, whereas pcre2_substring_get_bynumber() copies it into
new memory, obtained using the same memory allocation function that was
- used for the match data block. The first two arguments of these func-
- tions are a pointer to the match data block and a capturing group num-
- ber. A group number of zero extracts the substring that matched the
+ used for the match data block. The first two arguments of these func-
+ tions are a pointer to the match data block and a capturing group num-
+ ber. A group number of zero extracts the substring that matched the
entire pattern, and higher values extract the captured substrings.
The final arguments of pcre2_substring_copy_bynumber() are a pointer to
the buffer and a pointer to a variable that contains its length in code
- units. This is updated to contain the actual number of code units
- used, excluding the terminating zero.
+ units. This is updated to contain the actual number of code units used
+ for the extracted substring, excluding the terminating zero.
For pcre2_substring_get_bynumber() the third and fourth arguments point
- to variables that are updated with a pointer to the new memory and the
- number of code units that comprise the substring, again excluding the
- terminating zero. When the substring is no longer needed, the memory
+ to variables that are updated with a pointer to the new memory and the
+ number of code units that comprise the substring, again excluding the
+ terminating zero. When the substring is no longer needed, the memory
should be freed by calling pcre2_substring_free().
- The return value from these functions is zero for success, or one of
+ The return value from these functions is zero for success, or one of
these error codes:
PCRE2_ERROR_NOMEMORY
- The buffer was too small for pcre2_substring_copy_bynumber(), or the
+ The buffer was too small for pcre2_substring_copy_bynumber(), or the
attempt to get memory failed for pcre2_substring_get_bynumber().
PCRE2_ERROR_NOSUBSTRING
- No substring with the given number was captured. This could be because
- there is no capturing group of that number in the pattern, or because
+ No substring with the given number was captured. This could be because
+ there is no capturing group of that number in the pattern, or because
the group with that number did not participate in the match, or because
the ovector was too small to capture that group.
@@ -2233,28 +2235,28 @@
void pcre2_substring_list_free(PCRE2_SPTR *list);
- The pcre2_substring_list_get() function extracts all available sub-
- strings and builds a list of pointers to them, and a second list that
- contains their lengths (in code units), excluding a terminating zero
- that is added to each of them. All this is done in a single block of
- memory that is obtained using the same memory allocation function that
- was used to get the match data block.
+ The pcre2_substring_list_get() function extracts all available sub-
+ strings and builds a list of pointers to them. It also (optionally)
+ builds a second list that contains their lengths (in code units),
+ excluding a terminating zero that is added to each of them. All this is
+ done in a single block of memory that is obtained using the same memory
+ allocation function that was used to get the match data block.
- The address of the memory block is returned via listptr, which is also
+ The address of the memory block is returned via listptr, which is also
the start of the list of string pointers. The end of the list is marked
- by a NULL pointer. The address of the list of lengths is returned via
- lengthsptr. If your strings do not contain binary zeros and you do not
+ by a NULL pointer. The address of the list of lengths is returned via
+ lengthsptr. If your strings do not contain binary zeros and you do not
therefore need the lengths, you may supply NULL as the lengthsptr argu-
- ment to disable the creation of a list of lengths. The yield of the
- function is zero if all went well, or PCRE2_ERROR_NOMEMORY if the mem-
- ory block could not be obtained. When the list is no longer needed, it
+ ment to disable the creation of a list of lengths. The yield of the
+ function is zero if all went well, or PCRE2_ERROR_NOMEMORY if the mem-
+ ory block could not be obtained. When the list is no longer needed, it
should be freed by calling pcre2_substring_list_free().
If this function encounters a substring that is unset, which can happen
- when capturing subpattern number n+1 matches some part of the subject,
- but subpattern n has not been used at all, it returns an empty string.
- This can be distinguished from a genuine zero-length substring by
- inspecting the appropriate offset in the ovector, which contains
+ when capturing subpattern number n+1 matches some part of the subject,
+ but subpattern n has not been used at all, it returns an empty string.
+ This can be distinguished from a genuine zero-length substring by
+ inspecting the appropriate offset in the ovector, which contain
PCRE2_UNSET for unset substrings.
@@ -2274,26 +2276,25 @@
void pcre2_substring_free(PCRE2_UCHAR *buffer);
- To extract a substring by name, you first have to find associated num-
+ To extract a substring by name, you first have to find associated num-
ber. For example, for this pattern:
(a+)b(?<xxx>\d+)...
the number of the subpattern called "xxx" is 2. If the name is known to
- be unique (PCRE2_DUPNAMES was not set), you can find the number from
+ be unique (PCRE2_DUPNAMES was not set), you can find the number from
the name by calling pcre2_substring_number_from_name(). The first argu-
- ment is the compiled pattern, and the second is the name. The yield of
+ ment is the compiled pattern, and the second is the name. The yield of
the function is the subpattern number, PCRE2_ERROR_NOSUBSTRING if there
- is no subpattern of that name, or PCRE2_ERROR_NOUNIQUESUBSTRING if
+ is no subpattern of that name, or PCRE2_ERROR_NOUNIQUESUBSTRING if
there is more than one subpattern of that name.
Given the number, you can extract the substring directly, or use one of
- the functions described in the previous section. For convenience, there
- are also "byname" functions that correspond to the "bynumber" func-
- tions, the only difference being that the second argument is a name
- instead of a number. However, if PCRE2_DUPNAMES is set and there are
- duplicate names, the behaviour may not be what you want (see the next
- section).
+ the functions described above. For convenience, there are also "byname"
+ functions that correspond to the "bynumber" functions, the only differ-
+ ence being that the second argument is a name instead of a number. How-
+ ever, if PCRE2_DUPNAMES is set and there are duplicate names, the be-
+ haviour may not be what you want.
Warning: If the pattern uses the (?| feature to set up multiple subpat-
terns with the same number, as described in the section on duplicate
@@ -2331,8 +2332,8 @@
brackets are required only if the following character would be inter-
preted as part of the number or name. The number may be zero to include
the entire matched string. For example, if the pattern a(b)c is
- matched with "[abc]" and the replacement string "+$1$0$1+", the result
- is "[+babcb+]". Group insertion is done by calling pcre2_copy_byname()
+ matched with "=abc=" and the replacement string "+$1$0$1+", the result
+ is "=+babcb+=". Group insertion is done by calling pcre2_copy_byname()
or pcre2_copy_bynumber() as appropriate.
The first seven arguments of pcre2_substitute() are the same as for
@@ -2382,40 +2383,41 @@
pcre2_substring_get_byname() return the first substring corresponding
to the given name that is set. If none are set, PCRE2_ERROR_NOSUBSTRING
is returned. The pcre2_substring_number_from_name() function returns
- one of the numbers that are associated with the name, but it is not
- defined which it is.
+ the error PCRE2_ERROR_NOUNIQUESUBSTRING.
- If you want to get full details of all captured substrings for a given
- name, you must use the pcre2_substring_nametable_scan() function. The
- first argument is the compiled pattern, and the second is the name. If
- the third and fourth arguments are NULL, the function returns a group
- number (it is not defined which). Otherwise, the third and fourth argu-
- ments must be pointers to variables that are updated by the function.
- After it has run, they point to the first and last entries in the name-
- to-number table for the given name, and the function returns the length
- of each entry. In both cases, PCRE2_ERROR_NOSUBSTRING is returned if
- there are no entries for the given name.
+ If you want to get full details of all captured substrings for a given
+ name, you must use the pcre2_substring_nametable_scan() function. The
+ first argument is the compiled pattern, and the second is the name. If
+ the third and fourth arguments are NULL, the function returns a group
+ number for a unique name, or PCRE2_ERROR_NOUNIQUESUBSTRING otherwise.
+ When the third and fourth arguments are not NULL, they must be pointers
+ to variables that are updated by the function. After it has run, they
+ point to the first and last entries in the name-to-number table for the
+ given name, and the function returns the length of each entry in code
+ units. In both cases, PCRE2_ERROR_NOSUBSTRING is returned if there are
+ no entries for the given name.
+
The format of the name table is described above in the section entitled
- Information about a pattern above. Given all the relevant entries for
+ Information about a pattern above. Given all the relevant entries for
the name, you can extract each of their numbers, and hence the captured
data.
-FINDING ALL POSSIBLE MATCHES
+FINDING ALL POSSIBLE MATCHES AT ONE POSITION
- 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 want to find all possible matches, or the longest
- possible match at a given position, consider using the alternative
- matching function (see below) instead. If you cannot use the alterna-
- tive function, you can kludge it up by making use of the callout facil-
- ity, which is described in the pcre2callout documentation.
+ The traditional matching function uses a similar algorithm to Perl,
+ which stops when it finds the first match at a given point in the sub-
+ ject. If you want to find all possible matches, or the longest possible
+ match at a given position, consider using the alternative matching
+ function (see below) instead. If you cannot use the alternative func-
+ tion, you can kludge it up by making use of the callout facility, which
+ is described in the pcre2callout documentation.
What you have to do is to insert a callout right at the end of the pat-
- tern. When your callout function is called, extract and save the cur-
- rent matched substring. Then return 1, which forces pcre2_match() to
- backtrack and try other alternatives. Ultimately, when it runs out of
+ tern. When your callout function is called, extract and save the cur-
+ rent matched substring. Then return 1, which forces pcre2_match() to
+ backtrack and try other alternatives. Ultimately, when it runs out of
matches, pcre2_match() will yield PCRE2_ERROR_NOMATCH.
@@ -2427,26 +2429,26 @@
pcre2_match_context *mcontext,
int *workspace, PCRE2_SIZE wscount);
- The function pcre2_dfa_match() is called to match a subject string
- against a compiled pattern, using a matching algorithm that scans the
- subject string just once, and does not backtrack. This has different
- characteristics to the normal algorithm, and is not compatible with
- Perl. Some of the features of PCRE2 patterns are not supported. Never-
- theless, there are times when this kind of matching can be useful. For
- a discussion of the two matching algorithms, and a list of features
+ The function pcre2_dfa_match() is called to match a subject string
+ against a compiled pattern, using a matching algorithm that scans the
+ subject string just once, and does not backtrack. This has different
+ characteristics to the normal algorithm, and is not compatible with
+ Perl. Some of the features of PCRE2 patterns are not supported. Never-
+ theless, there are times when this kind of matching can be useful. For
+ a discussion of the two matching algorithms, and a list of features
that pcre2_dfa_match() does not support, see the pcre2matching documen-
tation.
- The arguments for the pcre2_dfa_match() function are the same as for
+ The arguments for the pcre2_dfa_match() function are the same as for
pcre2_match(), plus two extras. The ovector within the match data block
is used in a different way, and this is described below. The other com-
- mon arguments are used in the same way as for pcre2_match(), so their
+ mon arguments are used in the same way as for pcre2_match(), so their
description is not repeated here.
- The two additional arguments provide workspace for the function. The
- workspace vector should contain at least 20 elements. It is used for
+ The two additional arguments provide workspace for the function. The
+ workspace vector should contain at least 20 elements. It is used for
keeping track of multiple paths through the pattern tree. More
- workspace is needed for patterns and subjects where there are a lot of
+ workspace is needed for patterns and subjects where there are a lot of
potential matches.
Here is an example of a simple call to pcre2_dfa_match():
@@ -2466,45 +2468,45 @@
Option bits for pcre_dfa_match()
- The unused bits of the options argument for pcre2_dfa_match() must be
- zero. The only bits that may be set are PCRE2_ANCHORED, PCRE2_NOTBOL,
+ The unused bits of the options argument for pcre2_dfa_match() must be
+ zero. The only bits that may be set are PCRE2_ANCHORED, PCRE2_NOTBOL,
PCRE2_NOTEOL, PCRE2_NOTEMPTY, PCRE2_NOTEMPTY_ATSTART,
PCRE2_NO_UTF_CHECK, PCRE2_PARTIAL_HARD, PCRE2_PARTIAL_SOFT,
- PCRE2_DFA_SHORTEST, and PCRE2_DFA_RESTART. All but the last four of
- these are exactly the same as for pcre2_match(), so their description
+ PCRE2_DFA_SHORTEST, and PCRE2_DFA_RESTART. All but the last four of
+ these are exactly the same as for pcre2_match(), so their description
is not repeated here.
PCRE2_PARTIAL_HARD
PCRE2_PARTIAL_SOFT
- These have the same general effect as they do for pcre2_match(), but
- the details are slightly different. When PCRE2_PARTIAL_HARD is set for
- pcre2_dfa_match(), it returns PCRE2_ERROR_PARTIAL if the end of the
+ These have the same general effect as they do for pcre2_match(), but
+ the details are slightly different. When PCRE2_PARTIAL_HARD is set for
+ pcre2_dfa_match(), it returns PCRE2_ERROR_PARTIAL if the end of the
subject is reached and there is still at least one matching possibility
that requires additional characters. This happens even if some complete
- matches have already been found. When PCRE2_PARTIAL_SOFT is set, the
- return code PCRE2_ERROR_NOMATCH is converted into PCRE2_ERROR_PARTIAL
- if the end of the subject is reached, there have been no complete
+ matches have already been found. When PCRE2_PARTIAL_SOFT is set, the
+ return code PCRE2_ERROR_NOMATCH is converted into PCRE2_ERROR_PARTIAL
+ if the end of the subject is reached, there have been no complete
matches, but there is still at least one matching possibility. The por-
- tion of the string that was inspected when the longest partial match
+ tion of the string that was inspected when the longest partial match
was found is set as the first matching string in both cases. There is a
- more detailed discussion of partial and multi-segment matching, with
+ more detailed discussion of partial and multi-segment matching, with
examples, in the pcre2partial documentation.
PCRE2_DFA_SHORTEST
- Setting the PCRE2_DFA_SHORTEST option causes the matching algorithm to
+ Setting the PCRE2_DFA_SHORTEST option causes the matching algorithm to
stop as soon as it has found one match. Because of the way the alterna-
- tive algorithm works, this is necessarily the shortest possible match
+ tive algorithm works, this is necessarily the shortest possible match
at the first possible matching point in the subject string.
PCRE2_DFA_RESTART
- When pcre2_dfa_match() returns a partial match, it is possible to call
+ When pcre2_dfa_match() returns a partial match, it is possible to call
it again, with additional subject characters, and have it continue with
the same match. The PCRE2_DFA_RESTART option requests this action; when
- it is set, the workspace and wscount options must reference the same
- vector as before because data about the match so far is left in them
+ it is set, the workspace and wscount options must reference the same
+ vector as before because data about the match so far is left in them
after a partial match. There is more discussion of this facility in the
pcre2partial documentation.
@@ -2512,8 +2514,8 @@
When pcre2_dfa_match() succeeds, it may have matched more than one sub-
string in the subject. Note, however, that all the matches from one run
- of the function start at the same point in the subject. The shorter
- matches are all initial substrings of the longer matches. For example,
+ of the function start at the same point in the subject. The shorter
+ matches are all initial substrings of the longer matches. For example,
if the pattern
<.*>
@@ -2528,22 +2530,21 @@
<something> <something else>
<something> <something else> <something further>
- On success, the yield of the function is a number greater than zero,
- which is the number of matched substrings. The offsets of the sub-
- strings are returned in the ovector, and can be extracted in the same
- way as for pcre2_match(). They are returned in reverse order of
- length; that is, the longest matching string is given first. If there
- were too many matches to fit into the ovector, the yield of the func-
+ On success, the yield of the function is a number greater than zero,
+ which is the number of matched substrings. The offsets of the sub-
+ strings are returned in the ovector, and can be extracted in the same
+ way as for pcre2_match(). They are returned in reverse order of
+ length; that is, the longest matching string is given first. If there
+ were too many matches to fit into the ovector, the yield of the func-
tion is zero, and the vector is filled with the longest matches.
- NOTE: PCRE2'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 in backtracking into the repeated digits. For DFA
+ NOTE: PCRE2'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++". 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 PCRE2_NO_AUTO_POSSESS option when compil-
- ing.
+ repeat auch as "a\d+?" or set the PCRE2_NO_AUTO_POSSESS option when
+ compiling.
Error returns from pcre2_dfa_match()
@@ -2578,7 +2579,7 @@
PCRE2_ERROR_DFA_BADRESTART
- When pcre2_dfa_match() is called with the pcre2_dfa_RESTART option,
+ When pcre2_dfa_match() is called with the PCRE2_DFA_RESTART 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.
@@ -2586,21 +2587,21 @@
SEE ALSO
- pcre2build(3), pcre2libs(3), pcre2callout(3), pcre2matching(3),
- pcre2partial(3), pcre2posix(3), pcre2demo(3), pcre2sample(3),
- pcre2stack(3).
+ pcre2build(3), pcre2callout(3), pcre2demo(3), pcre2matching(3),
+ pcre2partial(3), pcre2posix(3), pcre2sample(3), pcre2stack(3),
+ pcre2unicode(3).
AUTHOR
Philip Hazel
University Computing Service
- Cambridge CB2 3QH, England.
+ Cambridge, England.
REVISION
- Last updated: 11 November 2014
+ Last updated: 21 November 2014
Copyright (c) 1997-2014 University of Cambridge.
------------------------------------------------------------------------------
@@ -3043,7 +3044,7 @@
Philip Hazel
University Computing Service
- Cambridge CB2 3QH, England.
+ Cambridge, England.
REVISION
@@ -3279,7 +3280,7 @@
Philip Hazel
University Computing Service
- Cambridge CB2 3QH, England.
+ Cambridge, England.
REVISION
@@ -3465,7 +3466,7 @@
Philip Hazel
University Computing Service
- Cambridge CB2 3QH, England.
+ Cambridge, England.
REVISION
@@ -3849,7 +3850,7 @@
Philip Hazel (FAQ by Zoltan Herczeg)
University Computing Service
- Cambridge CB2 3QH, England.
+ Cambridge, England.
REVISION
@@ -3917,7 +3918,7 @@
Philip Hazel
University Computing Service
- Cambridge CB2 3QH, England.
+ Cambridge, England.
REVISION
@@ -4136,7 +4137,7 @@
Philip Hazel
University Computing Service
- Cambridge CB2 3QH, England.
+ Cambridge, England.
REVISION
@@ -4576,7 +4577,7 @@
Philip Hazel
University Computing Service
- Cambridge CB2 3QH, England.
+ Cambridge, England.
REVISION
@@ -4801,7 +4802,7 @@
Philip Hazel
University Computing Service
- Cambridge CB2 3QH, England.
+ Cambridge, England.
REVISION
Modified: code/trunk/doc/pcre2api.3
===================================================================
--- code/trunk/doc/pcre2api.3 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/doc/pcre2api.3 2014-11-21 16:45:06 UTC (rev 157)
@@ -1,4 +1,4 @@
-.TH PCRE2API 3 "18 November 2014" "PCRE2 10.00"
+.TH PCRE2API 3 "21 November 2014" "PCRE2 10.00"
.SH NAME
PCRE2 - Perl-compatible regular expressions (revised API)
.sp
@@ -674,7 +674,7 @@
in the subject string. This limit is not relevant to \fBpcre2_dfa_match()\fP,
which ignores it.
.P
-When \fBpcre2_match()\fP is called with a pattern that was successfully
+When \fBpcre2_match()\fP is called with a pattern that was successfully
processed by \fBpcre2_jit_compile()\fP, the way in which matching is executed
is entirely different. However, there is still the possibility of runaway
matching that goes on for a very long time, and so the \fImatch_limit\fP value
@@ -740,7 +740,7 @@
.\" HREF
\fBpcre2build\fP
.\"
-documentation for details of how to build PCRE2.
+documentation for details of how to build PCRE2.
.P
Using the heap for recursion is a non-standard way of building PCRE2, for use
in environments that have limited stacks. Because of the greater use of memory
@@ -904,7 +904,7 @@
contains the compiled pattern and related data. The caller must free the memory
by calling \fBpcre2_code_free()\fP when it is no longer needed.
.P
-If the compile context argument \fIccontext\fP is NULL, memory for the compiled
+If the compile context argument \fIccontext\fP is NULL, memory for the compiled
pattern is obtained by calling \fBmalloc()\fP. Otherwise, it is obtained from
the same memory function that was used for the compile context.
.P
@@ -1569,16 +1569,18 @@
.P
The map consists of a number of fixed-size entries. PCRE2_INFO_NAMECOUNT gives
the number of entries, and PCRE2_INFO_NAMEENTRYSIZE gives the size of each
-entry; both of these return a \fBuint32_t\fP value. The entry size depends on
-the length of the longest name. PCRE2_INFO_NAMETABLE returns a pointer to the
-first entry of the table. This is a PCRE2_SPTR pointer to a block of code
-units. In the 8-bit library, the first two bytes of each entry are the number
-of the capturing parenthesis, 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.
+entry in code units; both of these return a \fBuint32_t\fP value. The entry
+size depends on the length of the longest name.
.P
+PCRE2_INFO_NAMETABLE returns a pointer to the first entry of the table. This is
+a PCRE2_SPTR pointer to a block of code units. In the 8-bit library, the first
+two bytes of each entry are the number of the capturing parenthesis, most
+significant byte first. In the 16-bit library, the pointer points to 16-bit
+code units, the first of which contains the parenthesis number. In the 32-bit
+library, the pointer points to 32-bit code units, the first of which contains
+the parenthesis number. The rest of the entry is the corresponding name, zero
+terminated.
+.P
The names are in alphabetical order. If (?| is used to create multiple groups
with the same number, as described in the
.\" HTML <a href="pcre2pattern.html#dupsubpatternnumber">
@@ -1621,14 +1623,14 @@
.sp
PCRE2_INFO_NEWLINE
.sp
-The output is a \fBuint32_t\fP with one of the following values:
+The output is a \fBuint32_t\fP with one of the following values:
.sp
PCRE2_NEWLINE_CR Carriage return (CR)
PCRE2_NEWLINE_LF Linefeed (LF)
PCRE2_NEWLINE_CRLF Carriage return, linefeed (CRLF)
PCRE2_NEWLINE_ANY Any Unicode line ending
PCRE2_NEWLINE_ANYCRLF Any of CR, LF, or CRLF
-.sp
+.sp
This specifies the default character sequence that will be recognized as
meaning "newline" while matching.
.sp
@@ -1670,7 +1672,7 @@
string that define the matched part of the subject and any substrings that were
captured. This is know as the \fIovector\fP.
.P
-Before calling \fBpcre2_match()\fP, \fBpcre2_dfa_match()\fP, or
+Before calling \fBpcre2_match()\fP, \fBpcre2_dfa_match()\fP, or
\fBpcre2_jit_match()\fP you must create a match data block by calling one of
the creation functions above. For \fBpcre2_match_data_create()\fP, the first
argument is the number of pairs of offsets in the \fIovector\fP. One pair of
@@ -1820,7 +1822,7 @@
.P
Setting PCRE2_ANCHORED at match time is not supported by the just-in-time (JIT)
compiler. If it is set, JIT matching is disabled and the normal interpretive
-code in \fBpcre2_match()\fP is run. The remaining options are supported for JIT
+code in \fBpcre2_match()\fP is run. The remaining options are supported for JIT
matching.
.sp
PCRE2_ANCHORED
@@ -1835,17 +1837,18 @@
.sp
This option specifies that first character of the subject string is not the
beginning of a line, so the circumflex metacharacter should not match before
-it. Setting this without PCRE2_MULTILINE (at compile time) causes circumflex
-never to match. This option affects only the behaviour of the circumflex
-metacharacter. It does not affect \eA.
+it. Setting this without having set PCRE2_MULTILINE at compile time causes
+circumflex never to match. This option affects only the behaviour of the
+circumflex metacharacter. It does not affect \eA.
.sp
PCRE2_NOTEOL
.sp
This option specifies that the end of the subject string is not the end of a
line, so the dollar metacharacter should not match it nor (except in multiline
-mode) a newline immediately before it. Setting this without PCRE2_MULTILINE (at
-compile time) causes dollar never to match. This option affects only the
-behaviour of the dollar metacharacter. It does not affect \eZ or \ez.
+mode) a newline immediately before it. Setting this without having set
+PCRE2_MULTILINE at compile time causes dollar never to match. This option
+affects only the behaviour of the dollar metacharacter. It does not affect \eZ
+or \ez.
.sp
PCRE2_NOTEMPTY
.sp
@@ -1857,13 +1860,16 @@
.sp
is applied to a string not beginning with "a" or "b", it matches an empty
string at the start of the subject. With PCRE2_NOTEMPTY set, this match is not
-valid, so PCRE2 searches further into the string for occurrences of "a" or "b".
+valid, so \fBpcre2_match()\fP searches further into the string for occurrences
+of "a" or "b".
.sp
PCRE2_NOTEMPTY_ATSTART
.sp
-This is like PCRE2_NOTEMPTY, except that an empty string match that is not at
-the start of the subject is permitted. If the pattern is anchored, such a match
-can occur only if the pattern contains \eK.
+This is like PCRE2_NOTEMPTY, except that it locks out an empty string match
+only at the first matching position, that is, at the start of the subject plus
+the starting offset. An empty string match later in the subject is permitted.
+If the pattern is anchored, such a match can occur only if the pattern contains
+\eK.
.sp
PCRE2_NO_UTF_CHECK
.sp
@@ -1913,8 +1919,8 @@
PCRE2_PARTIAL_SOFT (but not PCRE2_PARTIAL_HARD) is set, matching continues by
testing any remaining alternatives. Only if no complete match can be found is
PCRE2_ERROR_PARTIAL returned instead of PCRE2_ERROR_NOMATCH. In other words,
-PCRE2_PARTIAL_SOFT says that the caller is prepared to handle a partial match,
-but only if no complete match can be found.
+PCRE2_PARTIAL_SOFT specifies that the caller is prepared to handle a partial
+match, but only if no complete match can be found.
.P
If PCRE2_PARTIAL_HARD is set, it overrides PCRE2_PARTIAL_SOFT. In this case, if
a partial match is found, \fBpcre2_match()\fP immediately returns
@@ -1943,13 +1949,13 @@
.\"
During matching, the newline choice affects the behaviour of the dot,
circumflex, and dollar metacharacters. It may also alter the way the match
-position is advanced after a match failure for an unanchored pattern.
+starting position is advanced after a match failure for an unanchored pattern.
.P
-When PCRE2_NEWLINE_CRLF, PCRE2_NEWLINE_ANYCRLF, or PCRE2_NEWLINE_ANY is set,
-and a match attempt for an unanchored pattern fails when the current position
-is at a CRLF sequence, and the pattern contains no explicit matches for CR or
-LF characters, the match position is advanced by two characters instead of one,
-in other words, to after the CRLF.
+When PCRE2_NEWLINE_CRLF, PCRE2_NEWLINE_ANYCRLF, or PCRE2_NEWLINE_ANY is set as
+the newline convention, and a match attempt for an unanchored pattern fails
+when the current starting position is at a CRLF sequence, and the pattern
+contains no explicit matches for CR or LF characters, the match position is
+advanced by two characters instead of one, in other words, to after the CRLF.
.P
The above rule is a compromise that makes the most common cases work as
expected. For example, if the pattern is .+A (and the PCRE2_DOTALL option is
@@ -1960,8 +1966,8 @@
.P
An explicit match for CR of LF is either a literal appearance of one of those
characters in the pattern, or one of the \er or \en escape sequences. Implicit
-matches such as [^X] do not count, nor does \es (which includes CR and LF in
-the characters that it matches).
+matches such as [^X] do not count, nor does \es, even though it includes CR and
+LF in the characters that it matches.
.P
Notwithstanding the above, anomalous effects may still occur when CRLF is a
valid newline sequence and explicit \er or \en escapes appear in the pattern.
@@ -1981,15 +1987,15 @@
addition, further substrings from the subject may be picked out by
parenthesized parts of the pattern. Following the usage in Jeffrey Friedl's
book, this is called "capturing" in what follows, and the phrase "capturing
-subpattern" is used for a fragment of a pattern that picks out a substring.
-PCRE2 supports several other kinds of parenthesized subpattern that do not
-cause substrings to be captured. The \fBpcre2_pattern_info()\fP function can be
-used to find out how many capturing subpatterns there are in a compiled
-pattern.
+subpattern" or "capturing group" is used for a fragment of a pattern that picks
+out a substring. PCRE2 supports several other kinds of parenthesized subpattern
+that do not cause substrings to be captured. The \fBpcre2_pattern_info()\fP
+function can be used to find out how many capturing subpatterns there are in a
+compiled pattern.
.P
The overall matched string and any captured substrings are returned to the
-caller via a vector of PCRE2_SIZE values, called the \fBovector\fP. This is
-contained within the
+caller via a vector of PCRE2_SIZE values. This is called the \fBovector\fP, and
+is contained within the
.\" HTML <a href="#matchdatablock">
.\" </a>
match data block.
@@ -2062,7 +2068,7 @@
.
.
.\" HTML <a name="matchotherdata"></a>
-.SS "Other information about the match"
+.SH "OTHER INFORMATION ABOUT A MATCH"
.rs
.sp
.nf
@@ -2071,7 +2077,7 @@
.B PCRE2_SIZE pcre2_get_startchar(pcre2_match_data *\fImatch_data\fP);
.fi
.P
-In addition to the offsets in the ovector, other information about a match is
+As well as the offsets in the ovector, other information about a match is
retained in the match data block and can be retrieved by the above functions.
.P
When a (*MARK) name is to be passed back, \fBpcre2_get_mark()\fP returns a
@@ -2087,7 +2093,7 @@
.
.
.\" HTML <a name="errorlist"></a>
-.SS "Error return values from \fBpcre2_match()\fP"
+.SH "ERROR RETURNS FROM \fBpcre2_match()\fP"
.rs
.sp
If \fBpcre2_match()\fP fails, it returns a negative number. This can be
@@ -2127,7 +2133,7 @@
.sp
PCRE2_ERROR_BADOFFSET
.sp
-The value of \fIstartoffset\fP greater than the length of the subject.
+The value of \fIstartoffset\fP was greater than the length of the subject.
.sp
PCRE2_ERROR_BADOPTION
.sp
@@ -2200,8 +2206,8 @@
subpattern has been called recursively for the second time at the same position
in the subject string. Some simple patterns that might do this are detected and
faulted at compile time, but more complicated cases, in particular mutual
-recursions between two different subpatterns, cannot be detected until run
-time.
+recursions between two different subpatterns, cannot be detected until matching
+is attempted.
.sp
PCRE2_ERROR_RECURSIONLIMIT
.sp
@@ -2254,8 +2260,8 @@
.P
The final arguments of \fBpcre2_substring_copy_bynumber()\fP are a pointer to
the buffer and a pointer to a variable that contains its length in code units.
-This is updated to contain the actual number of code units used, excluding the
-terminating zero.
+This is updated to contain the actual number of code units used for the
+extracted substring, excluding the terminating zero.
.P
For \fBpcre2_substring_get_bynumber()\fP the third and fourth arguments point
to variables that are updated with a pointer to the new memory and the number
@@ -2290,10 +2296,11 @@
.fi
.P
The \fBpcre2_substring_list_get()\fP function extracts all available substrings
-and builds a list of pointers to them, and a second list that contains their
-lengths (in code units), excluding a terminating zero that is added to each of
-them. All this is done in a single block of memory that is obtained using the
-same memory allocation function that was used to get the match data block.
+and builds a list of pointers to them. It also (optionally) builds a second
+list that contains their lengths (in code units), excluding a terminating zero
+that is added to each of them. All this is done in a single block of memory
+that is obtained using the same memory allocation function that was used to get
+the match data block.
.P
The address of the memory block is returned via \fIlistptr\fP, which is also
the start of the list of string pointers. The end of the list is marked by a
@@ -2309,7 +2316,7 @@
capturing subpattern number \fIn+1\fP matches some part of the subject, but
subpattern \fIn\fP has not been used at all, it returns an empty string. This
can be distinguished from a genuine zero-length substring by inspecting the
-appropriate offset in the ovector, which contains PCRE2_UNSET for unset
+appropriate offset in the ovector, which contain PCRE2_UNSET for unset
substrings.
.
.
@@ -2347,11 +2354,10 @@
that name.
.P
Given the number, you can extract the substring directly, or use one of the
-functions described in the previous section. For convenience, there are also
-"byname" functions that correspond to the "bynumber" functions, the only
-difference being that the second argument is a name instead of a number.
-However, if PCRE2_DUPNAMES is set and there are duplicate names,
-the behaviour may not be what you want (see the next section).
+functions described above. For convenience, there are also "byname" functions
+that correspond to the "bynumber" functions, the only difference being that the
+second argument is a name instead of a number. However, if PCRE2_DUPNAMES is
+set and there are duplicate names, the behaviour may not be what you want.
.P
\fBWarning:\fP If the pattern uses the (?| feature to set up multiple
subpatterns with the same number, as described in the
@@ -2398,8 +2404,8 @@
Either a group number or a group name can be given for <n>. Curly brackets are
required only if the following character would be interpreted as part of the
number or name. The number may be zero to include the entire matched string.
-For example, if the pattern a(b)c is matched with "[abc]" and the replacement
-string "+$1$0$1+", the result is "[+babcb+]". Group insertion is done by
+For example, if the pattern a(b)c is matched with "=abc=" and the replacement
+string "+$1$0$1+", the result is "=+babcb+=". Group insertion is done by
calling \fBpcre2_copy_byname()\fP or \fBpcre2_copy_bynumber()\fP as
appropriate.
.P
@@ -2452,18 +2458,19 @@
When duplicates are present, \fBpcre2_substring_copy_byname()\fP and
\fBpcre2_substring_get_byname()\fP return the first substring corresponding to
the given name that is set. If none are set, PCRE2_ERROR_NOSUBSTRING is
-returned. The \fBpcre2_substring_number_from_name()\fP function returns one of
-the numbers that are associated with the name, but it is not defined which it
-is.
+returned. The \fBpcre2_substring_number_from_name()\fP function returns
+the error PCRE2_ERROR_NOUNIQUESUBSTRING.
.P
If you want to get full details of all captured substrings for a given name,
you must use the \fBpcre2_substring_nametable_scan()\fP function. The first
argument is the compiled pattern, and the second is the name. If the third and
-fourth arguments are NULL, the function returns a group number (it is not
-defined which). Otherwise, the third and fourth arguments must be pointers to
+fourth arguments are NULL, the function returns a group number for a unique
+name, or PCRE2_ERROR_NOUNIQUESUBSTRING otherwise.
+.P
+When the third and fourth arguments are not NULL, they must be pointers to
variables that are updated by the function. After it has run, they point to the
first and last entries in the name-to-number table for the given name, and the
-function returns the length of each entry. In both cases,
+function returns the length of each entry in code units. In both cases,
PCRE2_ERROR_NOSUBSTRING is returned if there are no entries for the given name.
.P
The format of the name table is described above in the section entitled
@@ -2476,15 +2483,15 @@
numbers, and hence the captured data.
.
.
-.SH "FINDING ALL POSSIBLE MATCHES"
+.SH "FINDING ALL POSSIBLE MATCHES AT ONE POSITION"
.rs
.sp
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
-want to find all possible matches, or the longest possible match at a given
-position, consider using the alternative matching function (see below) instead.
-If you cannot use the alternative function, you can kludge it up by making use
-of the callout facility, which is described in the
+when it finds the first match at a given point in the subject. If you want to
+find all possible matches, or the longest possible match at a given position,
+consider using the alternative matching function (see below) instead. If you
+cannot use the alternative function, you can kludge it up by making use of the
+callout facility, which is described in the
.\" HREF
\fBpcre2callout\fP
.\"
@@ -2628,11 +2635,10 @@
.P
NOTE: PCRE2's "auto-possessification" optimization usually applies to character
repeats at the end of a pattern (as well as internally). For example, the
-pattern "a\ed+" is compiled as if it were "a\ed++" because there is no point in
-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\ed+?") or set the
-PCRE2_NO_AUTO_POSSESS option when compiling.
+pattern "a\ed+" is compiled as if it were "a\ed++". 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 auch as "a\ed+?" or set
+the PCRE2_NO_AUTO_POSSESS option when compiling.
.
.
.SS "Error returns from \fBpcre2_dfa_match()\fP"
@@ -2673,7 +2679,7 @@
.sp
PCRE2_ERROR_DFA_BADRESTART
.sp
-When \fBpcre2_dfa_match()\fP is called with the \fBpcre2_dfa_RESTART\fP option,
+When \fBpcre2_dfa_match()\fP is called with the \fBPCRE2_DFA_RESTART\fP 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.
@@ -2682,9 +2688,9 @@
.SH "SEE ALSO"
.rs
.sp
-\fBpcre2build\fP(3), \fBpcre2libs\fP(3), \fBpcre2callout\fP(3),
+\fBpcre2build\fP(3), \fBpcre2callout\fP(3), \fBpcre2demo(3)\fP,
\fBpcre2matching\fP(3), \fBpcre2partial\fP(3), \fBpcre2posix\fP(3),
-\fBpcre2demo(3)\fP, \fBpcre2sample\fP(3), \fBpcre2stack\fP(3).
+\fBpcre2sample\fP(3), \fBpcre2stack\fP(3), \fBpcre2unicode\fP(3).
.
.
.SH AUTHOR
@@ -2701,6 +2707,6 @@
.rs
.sp
.nf
-Last updated: 18 November 2014
+Last updated: 21 November 2014
Copyright (c) 1997-2014 University of Cambridge.
.fi
Modified: code/trunk/src/pcre2_jit_compile.c
===================================================================
--- code/trunk/src/pcre2_jit_compile.c 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/src/pcre2_jit_compile.c 2014-11-21 16:45:06 UTC (rev 157)
@@ -3438,10 +3438,10 @@
}
}
else
- {
+ {
caseless = FALSE;
- othercase[0] = 0; /* Stops compiler warning - PH */
- }
+ othercase[0] = 0; /* Stops compiler warning - PH */
+ }
len_save = len;
cc_save = cc;
Modified: code/trunk/src/pcre2_match.c
===================================================================
--- code/trunk/src/pcre2_match.c 2014-11-21 12:19:37 UTC (rev 156)
+++ code/trunk/src/pcre2_match.c 2014-11-21 16:45:06 UTC (rev 157)
@@ -1401,11 +1401,11 @@
condition = TRUE;
/* Advance ecode past the assertion to the start of the first branch,
- but adjust it so that the general choosing code below works. If the
- assertion has a quantifier that allows zero repeats we must skip over
+ but adjust it so that the general choosing code below works. If the
+ assertion has a quantifier that allows zero repeats we must skip over
the BRAZERO. This is a lunatic thing to do, but somebody did! */
-
- if (*ecode == OP_BRAZERO) ecode++;
+
+ if (*ecode == OP_BRAZERO) ecode++;
ecode += GET(ecode, 1);
while (*ecode == OP_ALT) ecode += GET(ecode, 1);
ecode += 1 + LINK_SIZE - PRIV(OP_lengths)[condcode];
