+Starting with release 8.30, it is possible to compile two separate PCRE +libraries: the original, which supports 8-bit character strings (including +UTF-8 strings), and a second library that supports 16-bit character strings +(including UTF-16 strings). The build process allows either one or both to be +built. The majority of the work to make this possible was done by Zoltan +Herczeg. +
++The two libraries contain identical sets of functions, except that the names in +the 16-bit library start with pcre16_ instead of pcre_. To avoid +over-complication and reduce the documentation maintenance load, most of the +documentation describes the 8-bit library, with the differences for the 16-bit +library described separately in the +pcre16 +page. References to functions or structures of the form pcre[16]_xxx +should be read as meaning "pcre_xxx when using the 8-bit library and +pcre16_xxx when using the 16-bit library". +
+The current implementation of PCRE corresponds approximately with Perl 5.12, -including support for UTF-8 encoded strings and Unicode general category -properties. However, UTF-8 and Unicode support has to be explicitly enabled; it -is not the default. The Unicode tables correspond to Unicode release 6.0.0. +including support for UTF-8/16 encoded strings and Unicode general category +properties. However, UTF-8/16 and Unicode support has to be explicitly enabled; +it is not the default. The Unicode tables correspond to Unicode release 6.0.0.
In addition to the Perl-compatible matching function, PCRE contains an @@ -44,8 +63,8 @@ page.
PCRE is written in C and released as a C library. A number of people have written wrappers and interfaces of various kinds. In particular, Google Inc. -have provided a comprehensive C++ wrapper. This is now included as part of the -PCRE distribution. The +have provided a comprehensive C++ wrapper for the 8-bit library. This is now +included as part of the PCRE distribution. The pcrecpp page has details of this interface. Other people's contributions can be found in the Contrib directory at the primary FTP site, which is: @@ -73,13 +92,13 @@ found in the README and NON-UNIX-USE fil distribution.
-The library contains a number of undocumented internal functions and data +The libraries contains a number of undocumented internal functions and data tables that are used by more than one of the exported external functions, but which are not intended for use by external callers. Their names all begin with -"_pcre_", which hopefully will not provoke any name clashes. In some -environments, it is possible to control which external symbols are exported -when a shared library is built, and in these cases the undocumented symbols are -not exported. +"_pcre_" or "_pcre16_", which hopefully will not provoke any name clashes. In +some environments, it is possible to control which external symbols are +exported when a shared library is built, and in these cases the undocumented +symbols are not exported.
@@ -90,30 +109,31 @@ all the sections, except the pcredemo section, of searching. The sections are as follows:
pcre this document + pcre16 details of the 16-bit library pcre-config show PCRE installation configuration information pcreapi details of PCRE's native C API pcrebuild options for building PCRE pcrecallout details of the callout feature pcrecompat discussion of Perl compatibility - pcrecpp details of the C++ wrapper + pcrecpp details of the C++ wrapper for the 8-bit library pcredemo a demonstration C program that uses PCRE - pcregrep description of the pcregrep command + pcregrep description of the pcregrep command (8-bit only) pcrejit discussion of the just-in-time optimization support pcrelimits details of size and other limits pcrematching discussion of the two matching algorithms pcrepartial details of the partial matching facility pcrepattern syntax and semantics of supported regular expressions pcreperform discussion of performance issues - pcreposix the POSIX-compatible C API + pcreposix the POSIX-compatible C API for the 8-bit library pcreprecompile details of saving and re-using precompiled patterns pcresample discussion of the pcredemo program pcrestack discussion of stack usage pcresyntax quick syntax reference pcretest description of the pcretest testing command - pcreunicode discussion of Unicode and UTF-8 support + pcreunicode discussion of Unicode and UTF-8/16 supportIn addition, in the "man" and HTML formats, there is a short page for each -C library function, listing its arguments and results. +8-bit C library function, listing its arguments and results.
@@ -131,9 +151,9 @@ two digits 10, at the domain cam.ac.uk.
-Last updated: 24 August 2011
+Last updated: 10 January 2012
-Copyright © 1997-2011 University of Cambridge.
+Copyright © 1997-2012 University of Cambridge.
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