1 README file for PCRE (Perl-compatible regular expression library)
2 -----------------------------------------------------------------
4 The latest release of PCRE is always available in three alternative formats
7 ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.gz
8 ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.bz2
9 ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.zip
11 There is a mailing list for discussion about the development of PCRE at
15 Please read the NEWS file if you are upgrading from a previous release.
16 The contents of this README file are:
19 Documentation for PCRE
20 Contributions by users of PCRE
21 Building PCRE on non-Unix-like systems
22 Building PCRE without using autotools
23 Building PCRE using autotools
24 Retrieving configuration information
26 Cross-compiling using autotools
27 Using HP's ANSI C++ compiler (aCC)
38 PCRE is written in C, and it has its own API. There are three sets of functions,
39 one for the 8-bit library, which processes strings of bytes, one for the
40 16-bit library, which processes strings of 16-bit values, and one for the 32-bit
41 library, which processes strings of 32-bit values. The distribution also
42 includes a set of C++ wrapper functions (see the pcrecpp man page for details),
43 courtesy of Google Inc., which can be used to call the 8-bit PCRE library from
46 In addition, there is a set of C wrapper functions (again, just for the 8-bit
47 library) that are based on the POSIX regular expression API (see the pcreposix
48 man page). These end up in the library called libpcreposix. Note that this just
49 provides a POSIX calling interface to PCRE; the regular expressions themselves
50 still follow Perl syntax and semantics. The POSIX API is restricted, and does
51 not give full access to all of PCRE's facilities.
53 The header file for the POSIX-style functions is called pcreposix.h. The
54 official POSIX name is regex.h, but I did not want to risk possible problems
55 with existing files of that name by distributing it that way. To use PCRE with
56 an existing program that uses the POSIX API, pcreposix.h will have to be
57 renamed or pointed at by a link.
59 If you are using the POSIX interface to PCRE and there is already a POSIX regex
60 library installed on your system, as well as worrying about the regex.h header
61 file (as mentioned above), you must also take care when linking programs to
62 ensure that they link with PCRE's libpcreposix library. Otherwise they may pick
63 up the POSIX functions of the same name from the other library.
65 One way of avoiding this confusion is to compile PCRE with the addition of
66 -Dregcomp=PCREregcomp (and similarly for the other POSIX functions) to the
67 compiler flags (CFLAGS if you are using "configure" -- see below). This has the
68 effect of renaming the functions so that the names no longer clash. Of course,
69 you have to do the same thing for your applications, or write them using the
73 Documentation for PCRE
74 ----------------------
76 If you install PCRE in the normal way on a Unix-like system, you will end up
77 with a set of man pages whose names all start with "pcre". The one that is just
78 called "pcre" lists all the others. In addition to these man pages, the PCRE
79 documentation is supplied in two other forms:
81 1. There are files called doc/pcre.txt, doc/pcregrep.txt, and
82 doc/pcretest.txt in the source distribution. The first of these is a
83 concatenation of the text forms of all the section 3 man pages except
84 those that summarize individual functions. The other two are the text
85 forms of the section 1 man pages for the pcregrep and pcretest commands.
86 These text forms are provided for ease of scanning with text editors or
87 similar tools. They are installed in <prefix>/share/doc/pcre, where
88 <prefix> is the installation prefix (defaulting to /usr/local).
90 2. A set of files containing all the documentation in HTML form, hyperlinked
91 in various ways, and rooted in a file called index.html, is distributed in
92 doc/html and installed in <prefix>/share/doc/pcre/html.
94 Users of PCRE have contributed files containing the documentation for various
95 releases in CHM format. These can be found in the Contrib directory of the FTP
96 site (see next section).
99 Contributions by users of PCRE
100 ------------------------------
102 You can find contributions from PCRE users in the directory
104 ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/Contrib
106 There is a README file giving brief descriptions of what they are. Some are
107 complete in themselves; others are pointers to URLs containing relevant files.
108 Some of this material is likely to be well out-of-date. Several of the earlier
109 contributions provided support for compiling PCRE on various flavours of
110 Windows (I myself do not use Windows). Nowadays there is more Windows support
111 in the standard distribution, so these contibutions have been archived.
114 Building PCRE on non-Unix-like systems
115 --------------------------------------
117 For a non-Unix-like system, please read the comments in the file
118 NON-AUTOTOOLS-BUILD, though if your system supports the use of "configure" and
119 "make" you may be able to build PCRE using autotools in the same way as for
120 many Unix-like systems.
122 PCRE can also be configured using the GUI facility provided by CMake's
123 cmake-gui command. This creates Makefiles, solution files, etc. The file
124 NON-AUTOTOOLS-BUILD has information about CMake.
126 PCRE has been compiled on many different operating systems. It should be
127 straightforward to build PCRE on any system that has a Standard C compiler and
128 library, because it uses only Standard C functions.
131 Building PCRE without using autotools
132 -------------------------------------
134 The use of autotools (in particular, libtool) is problematic in some
135 environments, even some that are Unix or Unix-like. See the NON-AUTOTOOLS-BUILD
136 file for ways of building PCRE without using autotools.
139 Building PCRE using autotools
140 -----------------------------
142 If you are using HP's ANSI C++ compiler (aCC), please see the special note
143 in the section entitled "Using HP's ANSI C++ compiler (aCC)" below.
145 The following instructions assume the use of the widely used "configure; make;
146 make install" (autotools) process.
148 To build PCRE on system that supports autotools, first run the "configure"
149 command from the PCRE distribution directory, with your current directory set
150 to the directory where you want the files to be created. This command is a
151 standard GNU "autoconf" configuration script, for which generic instructions
152 are supplied in the file INSTALL.
154 Most commonly, people build PCRE within its own distribution directory, and in
155 this case, on many systems, just running "./configure" is sufficient. However,
156 the usual methods of changing standard defaults are available. For example:
158 CFLAGS='-O2 -Wall' ./configure --prefix=/opt/local
160 This command specifies that the C compiler should be run with the flags '-O2
161 -Wall' instead of the default, and that "make install" should install PCRE
162 under /opt/local instead of the default /usr/local.
164 If you want to build in a different directory, just run "configure" with that
165 directory as current. For example, suppose you have unpacked the PCRE source
166 into /source/pcre/pcre-xxx, but you want to build it in /build/pcre/pcre-xxx:
168 cd /build/pcre/pcre-xxx
169 /source/pcre/pcre-xxx/configure
171 PCRE is written in C and is normally compiled as a C library. However, it is
172 possible to build it as a C++ library, though the provided building apparatus
173 does not have any features to support this.
175 There are some optional features that can be included or omitted from the PCRE
176 library. They are also documented in the pcrebuild man page.
178 . By default, both shared and static libraries are built. You can change this
179 by adding one of these options to the "configure" command:
184 (See also "Shared libraries on Unix-like systems" below.)
186 . By default, only the 8-bit library is built. If you add --enable-pcre16 to
187 the "configure" command, the 16-bit library is also built. If you add
188 --enable-pcre32 to the "configure" command, the 32-bit library is also built.
189 If you want only the 16-bit or 32-bit library, use --disable-pcre8 to disable
190 building the 8-bit library.
192 . If you are building the 8-bit library and want to suppress the building of
193 the C++ wrapper library, you can add --disable-cpp to the "configure"
194 command. Otherwise, when "configure" is run without --disable-pcre8, it will
195 try to find a C++ compiler and C++ header files, and if it succeeds, it will
196 try to build the C++ wrapper.
198 . If you want to include support for just-in-time compiling, which can give
199 large performance improvements on certain platforms, add --enable-jit to the
200 "configure" command. This support is available only for certain hardware
201 architectures. If you try to enable it on an unsupported architecture, there
202 will be a compile time error.
204 . When JIT support is enabled, pcregrep automatically makes use of it, unless
205 you add --disable-pcregrep-jit to the "configure" command.
207 . If you want to make use of the support for UTF-8 Unicode character strings in
208 the 8-bit library, or UTF-16 Unicode character strings in the 16-bit library,
209 or UTF-32 Unicode character strings in the 32-bit library, you must add
210 --enable-utf to the "configure" command. Without it, the code for handling
211 UTF-8, UTF-16 and UTF-8 is not included in the relevant library. Even
212 when --enable-utf is included, the use of a UTF encoding still has to be
213 enabled by an option at run time. When PCRE is compiled with this option, its
214 input can only either be ASCII or UTF-8/16/32, even when running on EBCDIC
215 platforms. It is not possible to use both --enable-utf and --enable-ebcdic at
218 . There are no separate options for enabling UTF-8, UTF-16 and UTF-32
219 independently because that would allow ridiculous settings such as requesting
220 UTF-16 support while building only the 8-bit library. However, the option
221 --enable-utf8 is retained for backwards compatibility with earlier releases
222 that did not support 16-bit or 32-bit character strings. It is synonymous with
223 --enable-utf. It is not possible to configure one library with UTF support
224 and the other without in the same configuration.
226 . If, in addition to support for UTF-8/16/32 character strings, you want to
227 include support for the \P, \p, and \X sequences that recognize Unicode
228 character properties, you must add --enable-unicode-properties to the
229 "configure" command. This adds about 30K to the size of the library (in the
230 form of a property table); only the basic two-letter properties such as Lu
233 . You can build PCRE to recognize either CR or LF or the sequence CRLF or any
234 of the preceding, or any of the Unicode newline sequences as indicating the
235 end of a line. Whatever you specify at build time is the default; the caller
236 of PCRE can change the selection at run time. The default newline indicator
237 is a single LF character (the Unix standard). You can specify the default
238 newline indicator by adding --enable-newline-is-cr or --enable-newline-is-lf
239 or --enable-newline-is-crlf or --enable-newline-is-anycrlf or
240 --enable-newline-is-any to the "configure" command, respectively.
242 If you specify --enable-newline-is-cr or --enable-newline-is-crlf, some of
243 the standard tests will fail, because the lines in the test files end with
244 LF. Even if the files are edited to change the line endings, there are likely
245 to be some failures. With --enable-newline-is-anycrlf or
246 --enable-newline-is-any, many tests should succeed, but there may be some
249 . By default, the sequence \R in a pattern matches any Unicode line ending
250 sequence. This is independent of the option specifying what PCRE considers to
251 be the end of a line (see above). However, the caller of PCRE can restrict \R
252 to match only CR, LF, or CRLF. You can make this the default by adding
253 --enable-bsr-anycrlf to the "configure" command (bsr = "backslash R").
255 . When called via the POSIX interface, PCRE uses malloc() to get additional
256 storage for processing capturing parentheses if there are more than 10 of
257 them in a pattern. You can increase this threshold by setting, for example,
259 --with-posix-malloc-threshold=20
261 on the "configure" command.
263 . PCRE has a counter that can be set to limit the amount of resources it uses.
264 If the limit is exceeded during a match, the match fails. The default is ten
265 million. You can change the default by setting, for example,
267 --with-match-limit=500000
269 on the "configure" command. This is just the default; individual calls to
270 pcre_exec() can supply their own value. There is more discussion on the
273 . There is a separate counter that limits the depth of recursive function calls
274 during a matching process. This also has a default of ten million, which is
275 essentially "unlimited". You can change the default by setting, for example,
277 --with-match-limit-recursion=500000
279 Recursive function calls use up the runtime stack; running out of stack can
280 cause programs to crash in strange ways. There is a discussion about stack
281 sizes in the pcrestack man page.
283 . The default maximum compiled pattern size is around 64K. You can increase
284 this by adding --with-link-size=3 to the "configure" command. In the 8-bit
285 library, PCRE then uses three bytes instead of two for offsets to different
286 parts of the compiled pattern. In the 16-bit library, --with-link-size=3 is
287 the same as --with-link-size=4, which (in both libraries) uses four-byte
288 offsets. Increasing the internal link size reduces performance. In the 32-bit
289 library, the only supported link size is 4.
291 . You can build PCRE so that its internal match() function that is called from
292 pcre_exec() does not call itself recursively. Instead, it uses memory blocks
293 obtained from the heap via the special functions pcre_stack_malloc() and
294 pcre_stack_free() to save data that would otherwise be saved on the stack. To
295 build PCRE like this, use
297 --disable-stack-for-recursion
299 on the "configure" command. PCRE runs more slowly in this mode, but it may be
300 necessary in environments with limited stack sizes. This applies only to the
301 normal execution of the pcre_exec() function; if JIT support is being
302 successfully used, it is not relevant. Equally, it does not apply to
303 pcre_dfa_exec(), which does not use deeply nested recursion. There is a
304 discussion about stack sizes in the pcrestack man page.
306 . For speed, PCRE uses four tables for manipulating and identifying characters
307 whose code point values are less than 256. By default, it uses a set of
308 tables for ASCII encoding that is part of the distribution. If you specify
310 --enable-rebuild-chartables
312 a program called dftables is compiled and run in the default C locale when
313 you obey "make". It builds a source file called pcre_chartables.c. If you do
314 not specify this option, pcre_chartables.c is created as a copy of
315 pcre_chartables.c.dist. See "Character tables" below for further information.
317 . It is possible to compile PCRE for use on systems that use EBCDIC as their
318 character code (as opposed to ASCII/Unicode) by specifying
322 This automatically implies --enable-rebuild-chartables (see above). However,
323 when PCRE is built this way, it always operates in EBCDIC. It cannot support
324 both EBCDIC and UTF-8/16/32. There is a second option, --enable-ebcdic-nl25,
325 which specifies that the code value for the EBCDIC NL character is 0x25
326 instead of the default 0x15.
328 . In environments where valgrind is installed, if you specify
332 PCRE will use valgrind annotations to mark certain memory regions as
333 unaddressable. This allows it to detect invalid memory accesses, and is
334 mostly useful for debugging PCRE itself.
336 . In environments where the gcc compiler is used and lcov version 1.6 or above
337 is installed, if you specify
341 the build process implements a code coverage report for the test suite. The
342 report is generated by running "make coverage". If ccache is installed on
343 your system, it must be disabled when building PCRE for coverage reporting.
344 You can do this by setting the environment variable CCACHE_DISABLE=1 before
345 running "make" to build PCRE.
347 . The pcregrep program currently supports only 8-bit data files, and so
348 requires the 8-bit PCRE library. It is possible to compile pcregrep to use
349 libz and/or libbz2, in order to read .gz and .bz2 files (respectively), by
350 specifying one or both of
352 --enable-pcregrep-libz
353 --enable-pcregrep-libbz2
355 Of course, the relevant libraries must be installed on your system.
357 . The default size of internal buffer used by pcregrep can be set by, for
360 --with-pcregrep-bufsize=50K
362 The default value is 20K.
364 . It is possible to compile pcretest so that it links with the libreadline
365 or libedit libraries, by specifying, respectively,
367 --enable-pcretest-libreadline or --enable-pcretest-libedit
369 If this is done, when pcretest's input is from a terminal, it reads it using
370 the readline() function. This provides line-editing and history facilities.
371 Note that libreadline is GPL-licenced, so if you distribute a binary of
372 pcretest linked in this way, there may be licensing issues. These can be
373 avoided by linking with libedit (which has a BSD licence) instead.
375 Enabling libreadline causes the -lreadline option to be added to the pcretest
376 build. In many operating environments with a sytem-installed readline
377 library this is sufficient. However, in some environments (e.g. if an
378 unmodified distribution version of readline is in use), it may be necessary
379 to specify something like LIBS="-lncurses" as well. This is because, to quote
380 the readline INSTALL, "Readline uses the termcap functions, but does not link
381 with the termcap or curses library itself, allowing applications which link
382 with readline the to choose an appropriate library." If you get error
383 messages about missing functions tgetstr, tgetent, tputs, tgetflag, or tgoto,
384 this is the problem, and linking with the ncurses library should fix it.
386 The "configure" script builds the following files for the basic C library:
388 . Makefile the makefile that builds the library
389 . config.h build-time configuration options for the library
390 . pcre.h the public PCRE header file
391 . pcre-config script that shows the building settings such as CFLAGS
392 that were set for "configure"
393 . libpcre.pc ) data for the pkg-config command
397 . libtool script that builds shared and/or static libraries
399 Versions of config.h and pcre.h are distributed in the PCRE tarballs under the
400 names config.h.generic and pcre.h.generic. These are provided for those who
401 have to built PCRE without using "configure" or CMake. If you use "configure"
402 or CMake, the .generic versions are not used.
404 When building the 8-bit library, if a C++ compiler is found, the following
405 files are also built:
407 . libpcrecpp.pc data for the pkg-config command
408 . pcrecpparg.h header file for calling PCRE via the C++ wrapper
409 . pcre_stringpiece.h header for the C++ "stringpiece" functions
411 The "configure" script also creates config.status, which is an executable
412 script that can be run to recreate the configuration, and config.log, which
413 contains compiler output from tests that "configure" runs.
415 Once "configure" has run, you can run "make". This builds the the libraries
416 libpcre, libpcre16 and/or libpcre32, and a test program called pcretest. If you
417 enabled JIT support with --enable-jit, a test program called pcre_jit_test is
420 If the 8-bit library is built, libpcreposix and the pcregrep command are also
421 built, and if a C++ compiler was found on your system, and you did not disable
422 it with --disable-cpp, "make" builds the C++ wrapper library, which is called
423 libpcrecpp, as well as some test programs called pcrecpp_unittest,
424 pcre_scanner_unittest, and pcre_stringpiece_unittest.
426 The command "make check" runs all the appropriate tests. Details of the PCRE
427 tests are given below in a separate section of this document.
429 You can use "make install" to install PCRE into live directories on your
430 system. The following are installed (file names are all relative to the
431 <prefix> that is set when "configure" is run):
435 pcregrep (if 8-bit support is enabled)
439 libpcre16 (if 16-bit support is enabled)
440 libpcre32 (if 32-bit support is enabled)
441 libpcre (if 8-bit support is enabled)
442 libpcreposix (if 8-bit support is enabled)
443 libpcrecpp (if 8-bit and C++ support is enabled)
445 Configuration information (lib/pkgconfig):
450 libpcrecpp.pc (if C++ support is enabled)
452 Header files (include):
456 pcre_stringpiece.h ) if C++ support is enabled
460 Man pages (share/man/man{1,3}):
465 pcre*.3 (lots more pages, all starting "pcre")
467 HTML documentation (share/doc/pcre/html):
469 *.html (lots more pages, hyperlinked from index.html)
471 Text file documentation (share/doc/pcre):
478 pcre.txt (a concatenation of the man(3) pages)
479 pcretest.txt the pcretest man page
480 pcregrep.txt the pcregrep man page
481 pcre-config.txt the pcre-config man page
483 If you want to remove PCRE from your system, you can run "make uninstall".
484 This removes all the files that "make install" installed. However, it does not
485 remove any directories, because these are often shared with other programs.
488 Retrieving configuration information
489 ------------------------------------
491 Running "make install" installs the command pcre-config, which can be used to
492 recall information about the PCRE configuration and installation. For example:
494 pcre-config --version
496 prints the version number, and
500 outputs information about where the library is installed. This command can be
501 included in makefiles for programs that use PCRE, saving the programmer from
502 having to remember too many details.
504 The pkg-config command is another system for saving and retrieving information
505 about installed libraries. Instead of separate commands for each library, a
506 single command is used. For example:
508 pkg-config --cflags pcre
510 The data is held in *.pc files that are installed in a directory called
511 <prefix>/lib/pkgconfig.
517 The default distribution builds PCRE as shared libraries and static libraries,
518 as long as the operating system supports shared libraries. Shared library
519 support relies on the "libtool" script which is built as part of the
522 The libtool script is used to compile and link both shared and static
523 libraries. They are placed in a subdirectory called .libs when they are newly
524 built. The programs pcretest and pcregrep are built to use these uninstalled
525 libraries (by means of wrapper scripts in the case of shared libraries). When
526 you use "make install" to install shared libraries, pcregrep and pcretest are
527 automatically re-built to use the newly installed shared libraries before being
528 installed themselves. However, the versions left in the build directory still
529 use the uninstalled libraries.
531 To build PCRE using static libraries only you must use --disable-shared when
532 configuring it. For example:
534 ./configure --prefix=/usr/gnu --disable-shared
536 Then run "make" in the usual way. Similarly, you can use --disable-static to
537 build only shared libraries.
540 Cross-compiling using autotools
541 -------------------------------
543 You can specify CC and CFLAGS in the normal way to the "configure" command, in
544 order to cross-compile PCRE for some other host. However, you should NOT
545 specify --enable-rebuild-chartables, because if you do, the dftables.c source
546 file is compiled and run on the local host, in order to generate the inbuilt
547 character tables (the pcre_chartables.c file). This will probably not work,
548 because dftables.c needs to be compiled with the local compiler, not the cross
551 When --enable-rebuild-chartables is not specified, pcre_chartables.c is created
552 by making a copy of pcre_chartables.c.dist, which is a default set of tables
553 that assumes ASCII code. Cross-compiling with the default tables should not be
556 If you need to modify the character tables when cross-compiling, you should
557 move pcre_chartables.c.dist out of the way, then compile dftables.c by hand and
558 run it on the local host to make a new version of pcre_chartables.c.dist.
559 Then when you cross-compile PCRE this new version of the tables will be used.
562 Using HP's ANSI C++ compiler (aCC)
563 ----------------------------------
565 Unless C++ support is disabled by specifying the "--disable-cpp" option of the
566 "configure" script, you must include the "-AA" option in the CXXFLAGS
567 environment variable in order for the C++ components to compile correctly.
569 Also, note that the aCC compiler on PA-RISC platforms may have a defect whereby
570 needed libraries fail to get included when specifying the "-AA" compiler
571 option. If you experience unresolved symbols when linking the C++ programs,
572 use the workaround of specifying the following environment variable prior to
573 running the "configure" script:
575 CXXLDFLAGS="-lstd_v2 -lCsup_v2"
578 Using Sun's compilers for Solaris
579 ---------------------------------
581 A user reports that the following configurations work on Solaris 9 sparcv9 and
582 Solaris 9 x86 (32-bit):
584 Solaris 9 sparcv9: ./configure --disable-cpp CC=/bin/cc CFLAGS="-m64 -g"
585 Solaris 9 x86: ./configure --disable-cpp CC=/bin/cc CFLAGS="-g"
588 Using PCRE from MySQL
589 ---------------------
591 On systems where both PCRE and MySQL are installed, it is possible to make use
592 of PCRE from within MySQL, as an alternative to the built-in pattern matching.
593 There is a web page that tells you how to do this:
595 http://www.mysqludf.org/lib_mysqludf_preg/index.php
601 The command "make dist" creates three PCRE tarballs, in tar.gz, tar.bz2, and
602 zip formats. The command "make distcheck" does the same, but then does a trial
603 build of the new distribution to ensure that it works.
605 If you have modified any of the man page sources in the doc directory, you
606 should first run the PrepareRelease script before making a distribution. This
607 script creates the .txt and HTML forms of the documentation from the man pages.
613 To test the basic PCRE library on a Unix-like system, run the RunTest script.
614 There is another script called RunGrepTest that tests the options of the
615 pcregrep command. If the C++ wrapper library is built, three test programs
616 called pcrecpp_unittest, pcre_scanner_unittest, and pcre_stringpiece_unittest
617 are also built. When JIT support is enabled, another test program called
618 pcre_jit_test is built.
620 Both the scripts and all the program tests are run if you obey "make check" or
621 "make test". For other environments, see the instructions in
624 The RunTest script runs the pcretest test program (which is documented in its
625 own man page) on each of the relevant testinput files in the testdata
626 directory, and compares the output with the contents of the corresponding
627 testoutput files. Some tests are relevant only when certain build-time options
628 were selected. For example, the tests for UTF-8/16/32 support are run only if
629 --enable-utf was used. RunTest outputs a comment when it skips a test.
631 Many of the tests that are not skipped are run up to three times. The second
632 run forces pcre_study() to be called for all patterns except for a few in some
633 tests that are marked "never study" (see the pcretest program for how this is
634 done). If JIT support is available, the non-DFA tests are run a third time,
635 this time with a forced pcre_study() with the PCRE_STUDY_JIT_COMPILE option.
637 The entire set of tests is run once for each of the 8-bit, 16-bit and 32-bit
638 libraries that are enabled. If you want to run just one set of tests, call
639 RunTest with either the -8, -16 or -32 option.
641 RunTest uses a file called testtry to hold the main output from pcretest.
642 Other files whose names begin with "test" are used as working files in some
643 tests. To run pcretest on just one or more specific test files, give their
644 numbers as arguments to RunTest, for example:
648 You can also call RunTest with the single argument "list" to cause it to output
651 The first test file can be fed directly into the perltest.pl script to check
652 that Perl gives the same results. The only difference you should see is in the
653 first few lines, where the Perl version is given instead of the PCRE version.
655 The second set of tests check pcre_fullinfo(), pcre_study(),
656 pcre_copy_substring(), pcre_get_substring(), pcre_get_substring_list(), error
657 detection, and run-time flags that are specific to PCRE, as well as the POSIX
658 wrapper API. It also uses the debugging flags to check some of the internals of
661 If you build PCRE with a locale setting that is not the standard C locale, the
662 character tables may be different (see next paragraph). In some cases, this may
663 cause failures in the second set of tests. For example, in a locale where the
664 isprint() function yields TRUE for characters in the range 128-255, the use of
665 [:isascii:] inside a character class defines a different set of characters, and
666 this shows up in this test as a difference in the compiled code, which is being
667 listed for checking. Where the comparison test output contains [\x00-\x7f] the
668 test will contain [\x00-\xff], and similarly in some other cases. This is not a
671 The third set of tests checks pcre_maketables(), the facility for building a
672 set of character tables for a specific locale and using them instead of the
673 default tables. The tests make use of the "fr_FR" (French) locale. Before
674 running the test, the script checks for the presence of this locale by running
675 the "locale" command. If that command fails, or if it doesn't include "fr_FR"
676 in the list of available locales, the third test cannot be run, and a comment
677 is output to say why. If running this test produces instances of the error
679 ** Failed to set locale "fr_FR"
681 in the comparison output, it means that locale is not available on your system,
682 despite being listed by "locale". This does not mean that PCRE is broken.
684 [If you are trying to run this test on Windows, you may be able to get it to
685 work by changing "fr_FR" to "french" everywhere it occurs. Alternatively, use
686 RunTest.bat. The version of RunTest.bat included with PCRE 7.4 and above uses
687 Windows versions of test 2. More info on using RunTest.bat is included in the
688 document entitled NON-UNIX-USE.]
690 The fourth and fifth tests check the UTF-8/16/32 support and error handling and
691 internal UTF features of PCRE that are not relevant to Perl, respectively. The
692 sixth and seventh tests do the same for Unicode character properties support.
694 The eighth, ninth, and tenth tests check the pcre_dfa_exec() alternative
695 matching function, in non-UTF-8/16/32 mode, UTF-8/16/32 mode, and UTF-8/16/32
696 mode with Unicode property support, respectively.
698 The eleventh test checks some internal offsets and code size features; it is
699 run only when the default "link size" of 2 is set (in other cases the sizes
700 change) and when Unicode property support is enabled.
702 The twelfth test is run only when JIT support is available, and the thirteenth
703 test is run only when JIT support is not available. They test some JIT-specific
704 features such as information output from pcretest about JIT compilation.
706 The fourteenth, fifteenth, and sixteenth tests are run only in 8-bit mode, and
707 the seventeenth, eighteenth, and nineteenth tests are run only in 16/32-bit mode.
708 These are tests that generate different output in the two modes. They are for
709 general cases, UTF-8/16/32 support, and Unicode property support, respectively.
711 The twentieth test is run only in 16/32-bit mode. It tests some specific
712 16/32-bit features of the DFA matching engine.
714 The twenty-first and twenty-second tests are run only in 16/32-bit mode, when the
715 link size is set to 2 for the 16-bit library. They test reloading pre-compiled patterns.
717 The twenty-third and twenty-fourth tests are run only in 16-bit mode. They are for
718 general cases, and UTF-16 support, respectively.
720 The twenty-fifth and twenty-sixth tests are run only in 32-bit mode. They are for
721 general cases, and UTF-32 support, respectively.
726 For speed, PCRE uses four tables for manipulating and identifying characters
727 whose code point values are less than 256. The final argument of the
728 pcre_compile() function is a pointer to a block of memory containing the
729 concatenated tables. A call to pcre_maketables() can be used to generate a set
730 of tables in the current locale. If the final argument for pcre_compile() is
731 passed as NULL, a set of default tables that is built into the binary is used.
733 The source file called pcre_chartables.c contains the default set of tables. By
734 default, this is created as a copy of pcre_chartables.c.dist, which contains
735 tables for ASCII coding. However, if --enable-rebuild-chartables is specified
736 for ./configure, a different version of pcre_chartables.c is built by the
737 program dftables (compiled from dftables.c), which uses the ANSI C character
738 handling functions such as isalnum(), isalpha(), isupper(), islower(), etc. to
739 build the table sources. This means that the default C locale which is set for
740 your system will control the contents of these default tables. You can change
741 the default tables by editing pcre_chartables.c and then re-building PCRE. If
742 you do this, you should take care to ensure that the file does not get
743 automatically re-generated. The best way to do this is to move
744 pcre_chartables.c.dist out of the way and replace it with your customized
747 When the dftables program is run as a result of --enable-rebuild-chartables,
748 it uses the default C locale that is set on your system. It does not pay
749 attention to the LC_xxx environment variables. In other words, it uses the
750 system's default locale rather than whatever the compiling user happens to have
751 set. If you really do want to build a source set of character tables in a
752 locale that is specified by the LC_xxx variables, you can run the dftables
753 program by hand with the -L option. For example:
755 ./dftables -L pcre_chartables.c.special
757 The first two 256-byte tables provide lower casing and case flipping functions,
758 respectively. The next table consists of three 32-byte bit maps which identify
759 digits, "word" characters, and white space, respectively. These are used when
760 building 32-byte bit maps that represent character classes for code points less
763 The final 256-byte table has bits indicating various character types, as
766 1 white space character
770 16 alphanumeric or '_'
771 128 regular expression metacharacter or binary zero
773 You should not alter the set of characters that contain the 128 bit, as that
774 will cause PCRE to malfunction.
780 The distribution should contain the files listed below. Where a file name is
781 given as pcre[16|32]_xxx it means that there are three files, one with the name
782 pcre_xxx, one with the name pcre16_xx, and a third with the name pcre32_xxx.
784 (A) Source files of the PCRE library functions and their headers:
786 dftables.c auxiliary program for building pcre_chartables.c
787 when --enable-rebuild-chartables is specified
789 pcre_chartables.c.dist a default set of character tables that assume ASCII
790 coding; used, unless --enable-rebuild-chartables is
791 specified, by copying to pcre[16]_chartables.c
794 pcre[16|32]_byte_order.c )
795 pcre[16|32]_compile.c )
796 pcre[16|32]_config.c )
797 pcre[16|32]_dfa_exec.c )
799 pcre[16|32]_fullinfo.c )
800 pcre[16|32]_get.c ) sources for the functions in the library,
801 pcre[16|32]_globals.c ) and some internal functions that they use
802 pcre[16|32]_jit_compile.c )
803 pcre[16|32]_maketables.c )
804 pcre[16|32]_newline.c )
805 pcre[16|32]_refcount.c )
806 pcre[16|32]_string_utils.c )
807 pcre[16|32]_study.c )
808 pcre[16|32]_tables.c )
810 pcre[16|32]_version.c )
811 pcre[16|32]_xclass.c )
815 pcre16_utf16_utils.c )
816 pcre16_valid_utf16.c )
817 pcre32_utf32_utils.c )
818 pcre32_valid_utf32.c )
820 pcre[16|32]_printint.c ) debugging function that is used by pcretest,
821 ) and can also be #included in pcre_compile()
823 pcre.h.in template for pcre.h when built by "configure"
824 pcreposix.h header for the external POSIX wrapper API
825 pcre_internal.h header for internal use
826 sljit/* 16 files that make up the JIT compiler
827 ucp.h header for Unicode property handling
829 config.h.in template for config.h, which is built by "configure"
831 pcrecpp.h public header file for the C++ wrapper
832 pcrecpparg.h.in template for another C++ header file
833 pcre_scanner.h public header file for C++ scanner functions
835 pcre_scanner.cc ) source for the C++ wrapper library
837 pcre_stringpiece.h.in template for pcre_stringpiece.h, the header for the
838 C++ stringpiece functions
839 pcre_stringpiece.cc source for the C++ stringpiece functions
841 (B) Source files for programs that use PCRE:
843 pcredemo.c simple demonstration of coding calls to PCRE
844 pcregrep.c source of a grep utility that uses PCRE
845 pcretest.c comprehensive test program
849 132html script to turn "man" pages into HTML
850 AUTHORS information about the author of PCRE
851 ChangeLog log of changes to the code
852 CleanTxt script to clean nroff output for txt man pages
853 Detrail script to remove trailing spaces
854 HACKING some notes about the internals of PCRE
855 INSTALL generic installation instructions
856 LICENCE conditions for the use of PCRE
857 COPYING the same, using GNU's standard name
858 Makefile.in ) template for Unix Makefile, which is built by
860 Makefile.am ) the automake input that was used to create
862 NEWS important changes in this release
863 NON-UNIX-USE the previous name for NON-AUTOTOOLS-BUILD
864 NON-AUTOTOOLS-BUILD notes on building PCRE without using autotools
865 PrepareRelease script to make preparations for "make dist"
867 RunTest a Unix shell script for running tests
868 RunGrepTest a Unix shell script for pcregrep tests
869 aclocal.m4 m4 macros (generated by "aclocal")
870 config.guess ) files used by libtool,
871 config.sub ) used only when building a shared library
872 configure a configuring shell script (built by autoconf)
873 configure.ac ) the autoconf input that was used to build
874 ) "configure" and config.h
875 depcomp ) script to find program dependencies, generated by
877 doc/*.3 man page sources for PCRE
878 doc/*.1 man page sources for pcregrep and pcretest
879 doc/index.html.src the base HTML page
880 doc/html/* HTML documentation
881 doc/pcre.txt plain text version of the man pages
882 doc/pcretest.txt plain text documentation of test program
883 doc/perltest.txt plain text documentation of Perl test program
884 install-sh a shell script for installing files
885 libpcre16.pc.in template for libpcre16.pc for pkg-config
886 libpcre32.pc.in template for libpcre32.pc for pkg-config
887 libpcre.pc.in template for libpcre.pc for pkg-config
888 libpcreposix.pc.in template for libpcreposix.pc for pkg-config
889 libpcrecpp.pc.in template for libpcrecpp.pc for pkg-config
890 ltmain.sh file used to build a libtool script
891 missing ) common stub for a few missing GNU programs while
892 ) installing, generated by automake
893 mkinstalldirs script for making install directories
894 perltest.pl Perl test program
895 pcre-config.in source of script which retains PCRE information
896 pcre_jit_test.c test program for the JIT compiler
897 pcrecpp_unittest.cc )
898 pcre_scanner_unittest.cc ) test programs for the C++ wrapper
899 pcre_stringpiece_unittest.cc )
900 testdata/testinput* test data for main library tests
901 testdata/testoutput* expected test results
902 testdata/grep* input and output for pcregrep tests
903 testdata/* other supporting test files
905 (D) Auxiliary files for cmake support
907 cmake/COPYING-CMAKE-SCRIPTS
908 cmake/FindPackageHandleStandardArgs.cmake
909 cmake/FindEditline.cmake
910 cmake/FindReadline.cmake
914 (E) Auxiliary files for VPASCAL
921 (F) Auxiliary files for building PCRE "by hand"
923 pcre.h.generic ) a version of the public PCRE header file
924 ) for use in non-"configure" environments
925 config.h.generic ) a version of config.h for use in non-"configure"
930 RunTest.bat a script for running tests under Windows
933 Email local part: ph10
934 Email domain: cam.ac.uk
935 Last updated: 27 October 2012