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1 nigel 41 README file for PCRE (Perl-compatible regular expression library)
2     -----------------------------------------------------------------
3 nigel 3
4 nigel 43 The latest release of PCRE is always available from
6     ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.gz
7 ph10 123
8 ph10 111 There is a mailing list for discussion about the development of PCRE at
9 nigel 43
10 ph10 123 pcre-dev@exim.org
12 nigel 41 Please read the NEWS file if you are upgrading from a previous release.
13 ph10 109 The contents of this README file are:
14 nigel 23
15 ph10 109 The PCRE APIs
16     Documentation for PCRE
17     Contributions by users of PCRE
18     Building PCRE on non-Unix systems
19 ph10 122 Building PCRE on Unix-like systems
20     Retrieving configuration information on Unix-like systems
21 ph10 109 Shared libraries on Unix-like systems
22 ph10 122 Cross-compiling on Unix-like systems
23 ph10 109 Using HP's ANSI C++ compiler (aCC)
24 ph10 111 Making new tarballs
25 ph10 109 Testing PCRE
26     Character tables
27     File manifest
28 nigel 35
29 ph10 109
30 nigel 77 The PCRE APIs
31     -------------
33 ph10 128 PCRE is written in C, and it has its own API. The distribution also includes a
34     set of C++ wrapper functions (see the pcrecpp man page for details), courtesy
35     of Google Inc.
36 nigel 77
37 ph10 128 In addition, there is a set of C wrapper functions that are based on the POSIX
38     regular expression API (see the pcreposix man page). These end up in the
39     library called libpcreposix. Note that this just provides a POSIX calling
40     interface to PCRE; the regular expressions themselves still follow Perl syntax
41     and semantics. The POSIX API is restricted, and does not give full access to
42     all of PCRE's facilities.
43 nigel 77
44 ph10 109 The header file for the POSIX-style functions is called pcreposix.h. The
45     official POSIX name is regex.h, but I did not want to risk possible problems
46     with existing files of that name by distributing it that way. To use PCRE with
47     an existing program that uses the POSIX API, pcreposix.h will have to be
48     renamed or pointed at by a link.
50 nigel 73 If you are using the POSIX interface to PCRE and there is already a POSIX regex
51 ph10 109 library installed on your system, as well as worrying about the regex.h header
52     file (as mentioned above), you must also take care when linking programs to
53 nigel 73 ensure that they link with PCRE's libpcreposix library. Otherwise they may pick
54 ph10 109 up the POSIX functions of the same name from the other library.
55 nigel 49
56 ph10 109 One way of avoiding this confusion is to compile PCRE with the addition of
57 ph10 122 -Dregcomp=PCREregcomp (and similarly for the other POSIX functions) to the
58     compiler flags (CFLAGS if you are using "configure" -- see below). This has the
59     effect of renaming the functions so that the names no longer clash. Of course,
60     you have to do the same thing for your applications, or write them using the
61     new names.
62 nigel 73
63 ph10 109
64 nigel 75 Documentation for PCRE
65     ----------------------
67 ph10 122 If you install PCRE in the normal way on a Unix-like system, you will end up
68     with a set of man pages whose names all start with "pcre". The one that is just
69     called "pcre" lists all the others. In addition to these man pages, the PCRE
70     documentation is supplied in two other forms:
71 nigel 75
72 ph10 109 1. There are files called doc/pcre.txt, doc/pcregrep.txt, and
73     doc/pcretest.txt in the source distribution. The first of these is a
74     concatenation of the text forms of all the section 3 man pages except
75     those that summarize individual functions. The other two are the text
76     forms of the section 1 man pages for the pcregrep and pcretest commands.
77     These text forms are provided for ease of scanning with text editors or
78 ph10 123 similar tools. They are installed in <prefix>/share/doc/pcre, where
79 ph10 111 <prefix> is the installation prefix (defaulting to /usr/local).
80 nigel 75
81 ph10 109 2. A set of files containing all the documentation in HTML form, hyperlinked
82 ph10 123 in various ways, and rooted in a file called index.html, is distributed in
83 ph10 122 doc/html and installed in <prefix>/share/doc/pcre/html.
84 nigel 75
86 nigel 53 Contributions by users of PCRE
87     ------------------------------
89     You can find contributions from PCRE users in the directory
91     ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/Contrib
93 ph10 122 There is a README file giving brief descriptions of what they are. Some are
94     complete in themselves; others are pointers to URLs containing relevant files.
95 ph10 128 Some of this material is likely to be well out-of-date. Several of the earlier
96     contributions provided support for compiling PCRE on various flavours of
97     Windows (I myself do not use Windows). Nowadays there is more Windows support
98     in the standard distribution, so these contibutions have been archived.
99 nigel 53
101 ph10 109 Building PCRE on non-Unix systems
102     ---------------------------------
103 ph10 101
104 ph10 122 For a non-Unix system, please read the comments in the file NON-UNIX-USE,
105     though if your system supports the use of "configure" and "make" you may be
106     able to build PCRE in the same way as for Unix-like systems.
107 ph10 101
108 ph10 109 PCRE has been compiled on many different operating systems. It should be
109     straightforward to build PCRE on any system that has a Standard C compiler and
110     library, because it uses only Standard C functions.
111 ph10 101
113 ph10 122 Building PCRE on Unix-like systems
114     ----------------------------------
115 nigel 3
116 nigel 87 If you are using HP's ANSI C++ compiler (aCC), please see the special note
117     in the section entitled "Using HP's ANSI C++ compiler (aCC)" below.
119 ph10 145 The following instructions assume the use of the widely used "configure, make,
120     make install" process. There is also some experimental support for "cmake" in
121     the PCRE distribution, but it is incomplete and not documented. However, if you
122 ph10 144 are a "cmake" user, you might want to try it.
124 nigel 63 To build PCRE on a Unix-like system, first run the "configure" command from the
125     PCRE distribution directory, with your current directory set to the directory
126     where you want the files to be created. This command is a standard GNU
127     "autoconf" configuration script, for which generic instructions are supplied in
128 ph10 122 the file INSTALL.
129 nigel 3
130 nigel 53 Most commonly, people build PCRE within its own distribution directory, and in
131 ph10 109 this case, on many systems, just running "./configure" is sufficient. However,
132     the usual methods of changing standard defaults are available. For example:
133 nigel 53
134 nigel 41 CFLAGS='-O2 -Wall' ./configure --prefix=/opt/local
136     specifies that the C compiler should be run with the flags '-O2 -Wall' instead
137     of the default, and that "make install" should install PCRE under /opt/local
138 nigel 49 instead of the default /usr/local.
139 nigel 41
140 nigel 53 If you want to build in a different directory, just run "configure" with that
141     directory as current. For example, suppose you have unpacked the PCRE source
142     into /source/pcre/pcre-xxx, but you want to build it in /build/pcre/pcre-xxx:
144     cd /build/pcre/pcre-xxx
145     /source/pcre/pcre-xxx/configure
147 nigel 87 PCRE is written in C and is normally compiled as a C library. However, it is
148     possible to build it as a C++ library, though the provided building apparatus
149     does not have any features to support this.
151 nigel 63 There are some optional features that can be included or omitted from the PCRE
152     library. You can read more about them in the pcrebuild man page.
153 nigel 49
154 nigel 83 . If you want to suppress the building of the C++ wrapper library, you can add
155     --disable-cpp to the "configure" command. Otherwise, when "configure" is run,
156 ph10 128 it will try to find a C++ compiler and C++ header files, and if it succeeds,
157     it will try to build the C++ wrapper.
158 nigel 83
159 nigel 63 . If you want to make use of the support for UTF-8 character strings in PCRE,
160     you must add --enable-utf8 to the "configure" command. Without it, the code
161     for handling UTF-8 is not included in the library. (Even when included, it
162     still has to be enabled by an option at run time.)
164 nigel 75 . If, in addition to support for UTF-8 character strings, you want to include
165     support for the \P, \p, and \X sequences that recognize Unicode character
166     properties, you must add --enable-unicode-properties to the "configure"
167 nigel 91 command. This adds about 30K to the size of the library (in the form of a
168 nigel 75 property table); only the basic two-letter properties such as Lu are
169     supported.
171 nigel 93 . You can build PCRE to recognize either CR or LF or the sequence CRLF or any
172 ph10 149 of the preceding, or any of the Unicode newline sequences as indicating the
173     end of a line. Whatever you specify at build time is the default; the caller
174     of PCRE can change the selection at run time. The default newline indicator
175     is a single LF character (the Unix standard). You can specify the default
176     newline indicator by adding --enable-newline-is-cr or --enable-newline-is-lf
177     or --enable-newline-is-crlf or --enable-newline-is-anycrlf or
178     --enable-newline-is-any to the "configure" command, respectively.
179 ph10 109
180 ph10 149 If you specify --enable-newline-is-cr or --enable-newline-is-crlf, some of
181     the standard tests will fail, because the lines in the test files end with
182     LF. Even if the files are edited to change the line endings, there are likely
183     to be some failures. With --enable-newline-is-anycrlf or
184     --enable-newline-is-any, many tests should succeed, but there may be some
185     failures.
186 ph10 251
187     . By default, the sequence \R in a pattern matches any Unicode line ending
188     sequence. This is independent of the option specifying what PCRE considers to
189     be the end of a line (see above). However, the caller of PCRE can restrict \R
190     to match only CR, LF, or CRLF. You can make this the default by adding
191     --enable-bsr-anycrlf to the "configure" command (bsr = "backslash R").
192 nigel 63
193     . When called via the POSIX interface, PCRE uses malloc() to get additional
194     storage for processing capturing parentheses if there are more than 10 of
195 ph10 128 them in a pattern. You can increase this threshold by setting, for example,
196 nigel 63
197     --with-posix-malloc-threshold=20
199     on the "configure" command.
201 nigel 77 . PCRE has a counter that can be set to limit the amount of resources it uses.
202 nigel 63 If the limit is exceeded during a match, the match fails. The default is ten
203     million. You can change the default by setting, for example,
205     --with-match-limit=500000
207     on the "configure" command. This is just the default; individual calls to
208 ph10 122 pcre_exec() can supply their own value. There is more discussion on the
209     pcreapi man page.
210 nigel 63
211 nigel 91 . There is a separate counter that limits the depth of recursive function calls
212     during a matching process. This also has a default of ten million, which is
213     essentially "unlimited". You can change the default by setting, for example,
215     --with-match-limit-recursion=500000
217     Recursive function calls use up the runtime stack; running out of stack can
218     cause programs to crash in strange ways. There is a discussion about stack
219     sizes in the pcrestack man page.
221 nigel 63 . The default maximum compiled pattern size is around 64K. You can increase
222     this by adding --with-link-size=3 to the "configure" command. You can
223     increase it even more by setting --with-link-size=4, but this is unlikely
224 ph10 128 ever to be necessary. Increasing the internal link size will reduce
225     performance.
226 nigel 63
227 nigel 77 . You can build PCRE so that its internal match() function that is called from
228 ph10 122 pcre_exec() does not call itself recursively. Instead, it uses memory blocks
229     obtained from the heap via the special functions pcre_stack_malloc() and
230     pcre_stack_free() to save data that would otherwise be saved on the stack. To
231     build PCRE like this, use
232 nigel 73
233     --disable-stack-for-recursion
235     on the "configure" command. PCRE runs more slowly in this mode, but it may be
236 nigel 77 necessary in environments with limited stack sizes. This applies only to the
237     pcre_exec() function; it does not apply to pcre_dfa_exec(), which does not
238 ph10 122 use deeply nested recursion. There is a discussion about stack sizes in the
239     pcrestack man page.
240 nigel 73
241 ph10 128 . For speed, PCRE uses four tables for manipulating and identifying characters
242     whose code point values are less than 256. By default, it uses a set of
243     tables for ASCII encoding that is part of the distribution. If you specify
245     --enable-rebuild-chartables
247     a program called dftables is compiled and run in the default C locale when
248     you obey "make". It builds a source file called pcre_chartables.c. If you do
249     not specify this option, pcre_chartables.c is created as a copy of
250     pcre_chartables.c.dist. See "Character tables" below for further information.
252     . It is possible to compile PCRE for use on systems that use EBCDIC as their
253     default character code (as opposed to ASCII) by specifying
255     --enable-ebcdic
257     This automatically implies --enable-rebuild-chartables (see above).
259 ph10 109 The "configure" script builds the following files for the basic C library:
260 nigel 49
261 nigel 77 . Makefile is the makefile that builds the library
262     . config.h contains build-time configuration options for the library
263 ph10 109 . pcre.h is the public PCRE header file
264 nigel 77 . pcre-config is a script that shows the settings of "configure" options
265     . libpcre.pc is data for the pkg-config command
266 nigel 75 . libtool is a script that builds shared and/or static libraries
267 ph10 109 . RunTest is a script for running tests on the basic C library
268 nigel 77 . RunGrepTest is a script for running tests on the pcregrep command
269 nigel 41
270 ph10 123 Versions of config.h and pcre.h are distributed in the PCRE tarballs under
271 ph10 122 the names config.h.generic and pcre.h.generic. These are provided for the
272     benefit of those who have to built PCRE without the benefit of "configure". If
273     you use "configure", the .generic versions are not used.
274 nigel 77
275 ph10 109 If a C++ compiler is found, the following files are also built:
277     . libpcrecpp.pc is data for the pkg-config command
278     . pcrecpparg.h is a header file for programs that call PCRE via the C++ wrapper
279 nigel 77 . pcre_stringpiece.h is the header for the C++ "stringpiece" functions
281     The "configure" script also creates config.status, which is an executable
282     script that can be run to recreate the configuration, and config.log, which
283     contains compiler output from tests that "configure" runs.
285     Once "configure" has run, you can run "make". It builds two libraries, called
286 ph10 109 libpcre and libpcreposix, a test program called pcretest, a demonstration
287     program called pcredemo, and the pcregrep command. If a C++ compiler was found
288 ph10 122 on your system, "make" also builds the C++ wrapper library, which is called
289 ph10 109 libpcrecpp, and some test programs called pcrecpp_unittest,
290 ph10 122 pcre_scanner_unittest, and pcre_stringpiece_unittest. Building the C++ wrapper
291     can be disabled by adding --disable-cpp to the "configure" command.
292 nigel 3
293 ph10 109 The command "make check" runs all the appropriate tests. Details of the PCRE
294     tests are given below in a separate section of this document.
295 nigel 75
296 ph10 109 You can use "make install" to install PCRE into live directories on your
297     system. The following are installed (file names are all relative to the
298     <prefix> that is set when "configure" is run):
299 nigel 77
300 ph10 109 Commands (bin):
301     pcretest
302     pcregrep
303 ph10 111 pcre-config
304 ph10 109
305     Libraries (lib):
306     libpcre
307     libpcreposix
308     libpcrecpp (if C++ support is enabled)
310     Configuration information (lib/pkgconfig):
311     libpcre.pc
312 ph10 122 libpcrecpp.pc (if C++ support is enabled)
313 ph10 109
314     Header files (include):
315     pcre.h
316     pcreposix.h
317     pcre_scanner.h )
318     pcre_stringpiece.h ) if C++ support is enabled
319     pcrecpp.h )
320     pcrecpparg.h )
322     Man pages (share/man/man{1,3}):
323     pcregrep.1
324     pcretest.1
325     pcre.3
326     pcre*.3 (lots more pages, all starting "pcre")
328     HTML documentation (share/doc/pcre/html):
329     index.html
330     *.html (lots more pages, hyperlinked from index.html)
332     Text file documentation (share/doc/pcre):
333     AUTHORS
334     COPYING
335     ChangeLog
336     LICENCE
337     NEWS
338     README
339     pcre.txt (a concatenation of the man(3) pages)
340     pcretest.txt the pcretest man page
341     pcregrep.txt the pcregrep man page
343 ph10 111 Note that the pcredemo program that is built by "configure" is *not* installed
344 ph10 109 anywhere. It is a demonstration for programmers wanting to use PCRE.
346 nigel 77 If you want to remove PCRE from your system, you can run "make uninstall".
347     This removes all the files that "make install" installed. However, it does not
348     remove any directories, because these are often shared with other programs.
351 ph10 122 Retrieving configuration information on Unix-like systems
352     ---------------------------------------------------------
353 nigel 75
354 ph10 109 Running "make install" installs the command pcre-config, which can be used to
355     recall information about the PCRE configuration and installation. For example:
356 nigel 37
357 nigel 43 pcre-config --version
359     prints the version number, and
361 nigel 75 pcre-config --libs
362 nigel 43
363     outputs information about where the library is installed. This command can be
364     included in makefiles for programs that use PCRE, saving the programmer from
365     having to remember too many details.
367 nigel 75 The pkg-config command is another system for saving and retrieving information
368     about installed libraries. Instead of separate commands for each library, a
369     single command is used. For example:
370 nigel 43
371 nigel 75 pkg-config --cflags pcre
373     The data is held in *.pc files that are installed in a directory called
374 ph10 109 <prefix>/lib/pkgconfig.
375 nigel 75
377 nigel 63 Shared libraries on Unix-like systems
378     -------------------------------------
379 nigel 53
380 nigel 77 The default distribution builds PCRE as shared libraries and static libraries,
381     as long as the operating system supports shared libraries. Shared library
382     support relies on the "libtool" script which is built as part of the
383 nigel 53 "configure" process.
384 nigel 39
385 nigel 53 The libtool script is used to compile and link both shared and static
386     libraries. They are placed in a subdirectory called .libs when they are newly
387     built. The programs pcretest and pcregrep are built to use these uninstalled
388     libraries (by means of wrapper scripts in the case of shared libraries). When
389     you use "make install" to install shared libraries, pcregrep and pcretest are
390     automatically re-built to use the newly installed shared libraries before being
391 ph10 122 installed themselves. However, the versions left in the build directory still
392 nigel 53 use the uninstalled libraries.
394     To build PCRE using static libraries only you must use --disable-shared when
395 nigel 75 configuring it. For example:
396 nigel 3
397 nigel 43 ./configure --prefix=/usr/gnu --disable-shared
398 nigel 41
399 nigel 53 Then run "make" in the usual way. Similarly, you can use --disable-static to
400     build only shared libraries.
401 nigel 41
402 nigel 43
403 ph10 122 Cross-compiling on Unix-like systems
404     ------------------------------------
405 nigel 63
406     You can specify CC and CFLAGS in the normal way to the "configure" command, in
407 ph10 128 order to cross-compile PCRE for some other host. However, you should NOT
408     specify --enable-rebuild-chartables, because if you do, the dftables.c source
409     file is compiled and run on the local host, in order to generate the inbuilt
410     character tables (the pcre_chartables.c file). This will probably not work,
411     because dftables.c needs to be compiled with the local compiler, not the cross
412     compiler.
413 nigel 63
414 ph10 128 When --enable-rebuild-chartables is not specified, pcre_chartables.c is created
415     by making a copy of pcre_chartables.c.dist, which is a default set of tables
416     that assumes ASCII code. Cross-compiling with the default tables should not be
417     a problem.
418 nigel 63
419 ph10 128 If you need to modify the character tables when cross-compiling, you should
420     move pcre_chartables.c.dist out of the way, then compile dftables.c by hand and
421     run it on the local host to make a new version of pcre_chartables.c.dist.
422     Then when you cross-compile PCRE this new version of the tables will be used.
425 nigel 87 Using HP's ANSI C++ compiler (aCC)
426     ----------------------------------
428 nigel 93 Unless C++ support is disabled by specifying the "--disable-cpp" option of the
429 ph10 122 "configure" script, you must include the "-AA" option in the CXXFLAGS
430 nigel 87 environment variable in order for the C++ components to compile correctly.
432     Also, note that the aCC compiler on PA-RISC platforms may have a defect whereby
433     needed libraries fail to get included when specifying the "-AA" compiler
434     option. If you experience unresolved symbols when linking the C++ programs,
435     use the workaround of specifying the following environment variable prior to
436     running the "configure" script:
438     CXXLDFLAGS="-lstd_v2 -lCsup_v2"
440 ph10 123
441 ph10 111 Making new tarballs
442     -------------------
443 nigel 87
444 ph10 123 The command "make dist" creates three PCRE tarballs, in tar.gz, tar.bz2, and
445 ph10 155 zip formats. The command "make distcheck" does the same, but then does a trial
446     build of the new distribution to ensure that it works.
447 ph10 111
448 ph10 155 If you have modified any of the man page sources in the doc directory, you
449     should first run the PrepareRelease script before making a distribution. This
450     script creates the .txt and HTML forms of the documentation from the man pages.
451 ph10 111
452 ph10 155
453 nigel 41 Testing PCRE
454     ------------
456 ph10 122 To test the basic PCRE library on a Unix system, run the RunTest script that is
457     created by the configuring process. There is also a script called RunGrepTest
458     that tests the options of the pcregrep command. If the C++ wrapper library is
459     built, three test programs called pcrecpp_unittest, pcre_scanner_unittest, and
460 ph10 109 pcre_stringpiece_unittest are also built.
461 nigel 41
462 ph10 109 Both the scripts and all the program tests are run if you obey "make check" or
463     "make test". For other systems, see the instructions in NON-UNIX-USE.
464 nigel 77
465     The RunTest script runs the pcretest test program (which is documented in its
466 ph10 122 own man page) on each of the testinput files in the testdata directory in
467 nigel 77 turn, and compares the output with the contents of the corresponding testoutput
468 nigel 93 files. A file called testtry is used to hold the main output from pcretest
469 nigel 75 (testsavedregex is also used as a working file). To run pcretest on just one of
470     the test files, give its number as an argument to RunTest, for example:
471 nigel 41
472 nigel 63 RunTest 2
473 nigel 3
474 ph10 109 The first test file can also be fed directly into the perltest.pl script to
475     check that Perl gives the same results. The only difference you should see is
476     in the first few lines, where the Perl version is given instead of the PCRE
477     version.
478 nigel 3
479 nigel 49 The second set of tests check pcre_fullinfo(), pcre_info(), pcre_study(),
480     pcre_copy_substring(), pcre_get_substring(), pcre_get_substring_list(), error
481     detection, and run-time flags that are specific to PCRE, as well as the POSIX
482 ph10 122 wrapper API. It also uses the debugging flags to check some of the internals of
483 nigel 49 pcre_compile().
484 nigel 7
485 nigel 49 If you build PCRE with a locale setting that is not the standard C locale, the
486     character tables may be different (see next paragraph). In some cases, this may
487     cause failures in the second set of tests. For example, in a locale where the
488     isprint() function yields TRUE for characters in the range 128-255, the use of
489     [:isascii:] inside a character class defines a different set of characters, and
490     this shows up in this test as a difference in the compiled code, which is being
491     listed for checking. Where the comparison test output contains [\x00-\x7f] the
492     test will contain [\x00-\xff], and similarly in some other cases. This is not a
493     bug in PCRE.
495 nigel 63 The third set of tests checks pcre_maketables(), the facility for building a
496 nigel 25 set of character tables for a specific locale and using them instead of the
497 nigel 73 default tables. The tests make use of the "fr_FR" (French) locale. Before
498     running the test, the script checks for the presence of this locale by running
499     the "locale" command. If that command fails, or if it doesn't include "fr_FR"
500     in the list of available locales, the third test cannot be run, and a comment
501     is output to say why. If running this test produces instances of the error
502 nigel 25
503 nigel 73 ** Failed to set locale "fr_FR"
504 nigel 25
505     in the comparison output, it means that locale is not available on your system,
506     despite being listed by "locale". This does not mean that PCRE is broken.
508 ph10 142 [If you are trying to run this test on Windows, you may be able to get it to
509 ph10 139 work by changing "fr_FR" to "french" everywhere it occurs.]
511 nigel 63 The fourth test checks the UTF-8 support. It is not run automatically unless
512     PCRE is built with UTF-8 support. To do this you must set --enable-utf8 when
513     running "configure". This file can be also fed directly to the perltest script,
514     provided you are running Perl 5.8 or higher. (For Perl 5.6, a small patch,
515     commented in the script, can be be used.)
516 nigel 3
517 nigel 75 The fifth test checks error handling with UTF-8 encoding, and internal UTF-8
518     features of PCRE that are not relevant to Perl.
519 nigel 3
520 ph10 122 The sixth test checks the support for Unicode character properties. It it not
521     run automatically unless PCRE is built with Unicode property support. To to
522 nigel 77 this you must set --enable-unicode-properties when running "configure".
523 nigel 63
524 nigel 77 The seventh, eighth, and ninth tests check the pcre_dfa_exec() alternative
525     matching function, in non-UTF-8 mode, UTF-8 mode, and UTF-8 mode with Unicode
526     property support, respectively. The eighth and ninth tests are not run
527     automatically unless PCRE is build with the relevant support.
528 nigel 75
529 nigel 77
530 nigel 3 Character tables
531     ----------------
533 ph10 122 For speed, PCRE uses four tables for manipulating and identifying characters
534     whose code point values are less than 256. The final argument of the
535     pcre_compile() function is a pointer to a block of memory containing the
536     concatenated tables. A call to pcre_maketables() can be used to generate a set
537     of tables in the current locale. If the final argument for pcre_compile() is
538     passed as NULL, a set of default tables that is built into the binary is used.
539 nigel 3
540 ph10 128 The source file called pcre_chartables.c contains the default set of tables. By
541     default, this is created as a copy of pcre_chartables.c.dist, which contains
542     tables for ASCII coding. However, if --enable-rebuild-chartables is specified
543     for ./configure, a different version of pcre_chartables.c is built by the
544     program dftables (compiled from dftables.c), which uses the ANSI C character
545     handling functions such as isalnum(), isalpha(), isupper(), islower(), etc. to
546     build the table sources. This means that the default C locale which is set for
547     your system will control the contents of these default tables. You can change
548     the default tables by editing pcre_chartables.c and then re-building PCRE. If
549     you do this, you should take care to ensure that the file does not get
550     automatically re-generated. The best way to do this is to move
551     pcre_chartables.c.dist out of the way and replace it with your customized
552     tables.
553 nigel 3
554 ph10 128 When the dftables program is run as a result of --enable-rebuild-chartables,
555     it uses the default C locale that is set on your system. It does not pay
556     attention to the LC_xxx environment variables. In other words, it uses the
557     system's default locale rather than whatever the compiling user happens to have
558     set. If you really do want to build a source set of character tables in a
559     locale that is specified by the LC_xxx variables, you can run the dftables
560     program by hand with the -L option. For example:
562     ./dftables -L pcre_chartables.c.special
564 nigel 25 The first two 256-byte tables provide lower casing and case flipping functions,
565     respectively. The next table consists of three 32-byte bit maps which identify
566     digits, "word" characters, and white space, respectively. These are used when
567 ph10 111 building 32-byte bit maps that represent character classes for code points less
568 ph10 109 than 256.
569 nigel 25
570     The final 256-byte table has bits indicating various character types, as
571 nigel 3 follows:
573     1 white space character
574     2 letter
575     4 decimal digit
576     8 hexadecimal digit
577     16 alphanumeric or '_'
578     128 regular expression metacharacter or binary zero
580     You should not alter the set of characters that contain the 128 bit, as that
581     will cause PCRE to malfunction.
584 ph10 109 File manifest
585     -------------
586 nigel 3
587 nigel 41 The distribution should contain the following files:
588 nigel 3
589 ph10 109 (A) Source files of the PCRE library functions and their headers:
590 nigel 3
591 ph10 128 dftables.c auxiliary program for building pcre_chartables.c
592     when --enable-rebuild-chartables is specified
593 ph10 111
594 ph10 128 pcre_chartables.c.dist a default set of character tables that assume ASCII
595     coding; used, unless --enable-rebuild-chartables is
596     specified, by copying to pcre_chartables.c
597 ph10 111
598 ph10 128 pcreposix.c )
599     pcre_compile.c )
600     pcre_config.c )
601     pcre_dfa_exec.c )
602     pcre_exec.c )
603     pcre_fullinfo.c )
604     pcre_get.c ) sources for the functions in the library,
605     pcre_globals.c ) and some internal functions that they use
606     pcre_info.c )
607     pcre_maketables.c )
608     pcre_newline.c )
609     pcre_ord2utf8.c )
610     pcre_refcount.c )
611     pcre_study.c )
612     pcre_tables.c )
613     pcre_try_flipped.c )
614     pcre_ucp_searchfuncs.c )
615     pcre_valid_utf8.c )
616     pcre_version.c )
617     pcre_xclass.c )
618     pcre_printint.src ) debugging function that is #included in pcretest,
619     ) and can also be #included in pcre_compile()
620     pcre.h.in template for pcre.h when built by "configure"
621     pcreposix.h header for the external POSIX wrapper API
622     pcre_internal.h header for internal use
623     ucp.h ) headers concerned with
624     ucpinternal.h ) Unicode property handling
625     ucptable.h ) (this one is the data table)
626 ph10 111
627 ph10 128 config.h.in template for config.h, which is built by "configure"
628 ph10 111
629 ph10 128 pcrecpp.h public header file for the C++ wrapper
630     pcrecpparg.h.in template for another C++ header file
631     pcre_scanner.h public header file for C++ scanner functions
632     pcrecpp.cc )
633     pcre_scanner.cc ) source for the C++ wrapper library
634 ph10 111
635 ph10 128 pcre_stringpiece.h.in template for pcre_stringpiece.h, the header for the
636     C++ stringpiece functions
637     pcre_stringpiece.cc source for the C++ stringpiece functions
639 ph10 109 (B) Source files for programs that use PCRE:
640 nigel 75
641 ph10 128 pcredemo.c simple demonstration of coding calls to PCRE
642     pcregrep.c source of a grep utility that uses PCRE
643     pcretest.c comprehensive test program
644 ph10 111
645     (C) Auxiliary files:
647 ph10 128 132html script to turn "man" pages into HTML
648     AUTHORS information about the author of PCRE
649     ChangeLog log of changes to the code
650     CleanTxt script to clean nroff output for txt man pages
651     Detrail script to remove trailing spaces
652     HACKING some notes about the internals of PCRE
653     INSTALL generic installation instructions
654     LICENCE conditions for the use of PCRE
655     COPYING the same, using GNU's standard name
656     Makefile.in ) template for Unix Makefile, which is built by
657     ) "configure"
658     Makefile.am ) the automake input that was used to create
659     ) Makefile.in
660     NEWS important changes in this release
661     NON-UNIX-USE notes on building PCRE on non-Unix systems
662     PrepareRelease script to make preparations for "make dist"
663     README this file
664 ph10 138 RunTest a Unix shell script for running tests
665     RunGrepTest a Unix shell script for pcregrep tests
666 ph10 128 aclocal.m4 m4 macros (generated by "aclocal")
667     config.guess ) files used by libtool,
668     config.sub ) used only when building a shared library
669     configure a configuring shell script (built by autoconf)
670     configure.ac ) the autoconf input that was used to build
671     ) "configure" and config.h
672     depcomp ) script to find program dependencies, generated by
673     ) automake
674     doc/*.3 man page sources for the PCRE functions
675     doc/*.1 man page sources for pcregrep and pcretest
676     doc/index.html.src the base HTML page
677     doc/html/* HTML documentation
678     doc/pcre.txt plain text version of the man pages
679     doc/pcretest.txt plain text documentation of test program
680     doc/perltest.txt plain text documentation of Perl test program
681     install-sh a shell script for installing files
682     libpcre.pc.in template for libpcre.pc for pkg-config
683     libpcrecpp.pc.in template for libpcrecpp.pc for pkg-config
684     ltmain.sh file used to build a libtool script
685     missing ) common stub for a few missing GNU programs while
686     ) installing, generated by automake
687     mkinstalldirs script for making install directories
688     perltest.pl Perl test program
689     pcre-config.in source of script which retains PCRE information
690 ph10 111 pcrecpp_unittest.cc )
691     pcre_scanner_unittest.cc ) test programs for the C++ wrapper
692     pcre_stringpiece_unittest.cc )
693 ph10 128 testdata/testinput* test data for main library tests
694     testdata/testoutput* expected test results
695     testdata/grep* input and output for pcregrep tests
696 ph10 111
697 ph10 109 (D) Auxiliary files for cmake support
698 nigel 3
699 ph10 109 CMakeLists.txt
700 ph10 111 config-cmake.h.in
701 nigel 29
702 ph10 109 (E) Auxiliary files for VPASCAL
703 nigel 29
704 nigel 63 makevp.bat
705 ph10 135 makevp_c.txt
706     makevp_l.txt
707 ph10 111 pcregexp.pas
709     (F) Auxiliary files for building PCRE "by hand"
711 ph10 128 pcre.h.generic ) a version of the public PCRE header file
712     ) for use in non-"configure" environments
713     config.h.generic ) a version of config.h for use in non-"configure"
714     ) environments
715 ph10 111
716 ph10 109 (F) Miscellaneous
717 nigel 63
718 ph10 109 RunTest.bat a script for running tests under Windows
720 nigel 77 Philip Hazel
721     Email local part: ph10
722     Email domain: cam.ac.uk
723 ph10 251 Last updated: 17 September 2007


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