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Wed Apr 4 14:06:52 2007 UTC (7 years, 5 months ago) by ph10
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Reworked all the WIN32 __declspec stuff in the hope of getting it right.

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
5    
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
11    
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     -------------
32    
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.
49    
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     ----------------------
66    
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
85    
86 nigel 53 Contributions by users of PCRE
87     ------------------------------
88    
89     You can find contributions from PCRE users in the directory
90    
91     ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/Contrib
92    
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
100    
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
112    
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.
118    
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.
123    
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
135    
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:
143    
144     cd /build/pcre/pcre-xxx
145     /source/pcre/pcre-xxx/configure
146    
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.
150    
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.)
163    
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.
170    
171 nigel 93 . You can build PCRE to recognize either CR or LF or the sequence CRLF or any
172     of the Unicode newline sequences as indicating the end of a line. Whatever
173     you specify at build time is the default; the caller of PCRE can change the
174     selection at run time. The default newline indicator is a single LF character
175     (the Unix standard). You can specify the default newline indicator by adding
176     --newline-is-cr or --newline-is-lf or --newline-is-crlf or --newline-is-any
177     to the "configure" command, respectively.
178 ph10 109
179     If you specify --newline-is-cr or --newline-is-crlf, some of the standard
180     tests will fail, because the lines in the test files end with LF. Even if
181 ph10 99 the files are edited to change the line endings, there are likely to be some
182     failures. With --newline-is-any, many tests should succeed, but there may be
183     some failures.
184 nigel 63
185     . When called via the POSIX interface, PCRE uses malloc() to get additional
186     storage for processing capturing parentheses if there are more than 10 of
187 ph10 128 them in a pattern. You can increase this threshold by setting, for example,
188 nigel 63
189     --with-posix-malloc-threshold=20
190    
191     on the "configure" command.
192    
193 nigel 77 . PCRE has a counter that can be set to limit the amount of resources it uses.
194 nigel 63 If the limit is exceeded during a match, the match fails. The default is ten
195     million. You can change the default by setting, for example,
196    
197     --with-match-limit=500000
198    
199     on the "configure" command. This is just the default; individual calls to
200 ph10 122 pcre_exec() can supply their own value. There is more discussion on the
201     pcreapi man page.
202 nigel 63
203 nigel 91 . There is a separate counter that limits the depth of recursive function calls
204     during a matching process. This also has a default of ten million, which is
205     essentially "unlimited". You can change the default by setting, for example,
206    
207     --with-match-limit-recursion=500000
208    
209     Recursive function calls use up the runtime stack; running out of stack can
210     cause programs to crash in strange ways. There is a discussion about stack
211     sizes in the pcrestack man page.
212    
213 nigel 63 . The default maximum compiled pattern size is around 64K. You can increase
214     this by adding --with-link-size=3 to the "configure" command. You can
215     increase it even more by setting --with-link-size=4, but this is unlikely
216 ph10 128 ever to be necessary. Increasing the internal link size will reduce
217     performance.
218 nigel 63
219 nigel 77 . You can build PCRE so that its internal match() function that is called from
220 ph10 122 pcre_exec() does not call itself recursively. Instead, it uses memory blocks
221     obtained from the heap via the special functions pcre_stack_malloc() and
222     pcre_stack_free() to save data that would otherwise be saved on the stack. To
223     build PCRE like this, use
224 nigel 73
225     --disable-stack-for-recursion
226    
227     on the "configure" command. PCRE runs more slowly in this mode, but it may be
228 nigel 77 necessary in environments with limited stack sizes. This applies only to the
229     pcre_exec() function; it does not apply to pcre_dfa_exec(), which does not
230 ph10 122 use deeply nested recursion. There is a discussion about stack sizes in the
231     pcrestack man page.
232 nigel 73
233 ph10 128 . For speed, PCRE uses four tables for manipulating and identifying characters
234     whose code point values are less than 256. By default, it uses a set of
235     tables for ASCII encoding that is part of the distribution. If you specify
236    
237     --enable-rebuild-chartables
238    
239     a program called dftables is compiled and run in the default C locale when
240     you obey "make". It builds a source file called pcre_chartables.c. If you do
241     not specify this option, pcre_chartables.c is created as a copy of
242     pcre_chartables.c.dist. See "Character tables" below for further information.
243    
244     . It is possible to compile PCRE for use on systems that use EBCDIC as their
245     default character code (as opposed to ASCII) by specifying
246    
247     --enable-ebcdic
248    
249     This automatically implies --enable-rebuild-chartables (see above).
250    
251 ph10 109 The "configure" script builds the following files for the basic C library:
252 nigel 49
253 nigel 77 . Makefile is the makefile that builds the library
254     . config.h contains build-time configuration options for the library
255 ph10 109 . pcre.h is the public PCRE header file
256 nigel 77 . pcre-config is a script that shows the settings of "configure" options
257     . libpcre.pc is data for the pkg-config command
258 nigel 75 . libtool is a script that builds shared and/or static libraries
259 ph10 109 . RunTest is a script for running tests on the basic C library
260 nigel 77 . RunGrepTest is a script for running tests on the pcregrep command
261 nigel 41
262 ph10 123 Versions of config.h and pcre.h are distributed in the PCRE tarballs under
263 ph10 122 the names config.h.generic and pcre.h.generic. These are provided for the
264     benefit of those who have to built PCRE without the benefit of "configure". If
265     you use "configure", the .generic versions are not used.
266 nigel 77
267 ph10 109 If a C++ compiler is found, the following files are also built:
268    
269     . libpcrecpp.pc is data for the pkg-config command
270     . pcrecpparg.h is a header file for programs that call PCRE via the C++ wrapper
271 nigel 77 . pcre_stringpiece.h is the header for the C++ "stringpiece" functions
272    
273     The "configure" script also creates config.status, which is an executable
274     script that can be run to recreate the configuration, and config.log, which
275     contains compiler output from tests that "configure" runs.
276    
277     Once "configure" has run, you can run "make". It builds two libraries, called
278 ph10 109 libpcre and libpcreposix, a test program called pcretest, a demonstration
279     program called pcredemo, and the pcregrep command. If a C++ compiler was found
280 ph10 122 on your system, "make" also builds the C++ wrapper library, which is called
281 ph10 109 libpcrecpp, and some test programs called pcrecpp_unittest,
282 ph10 122 pcre_scanner_unittest, and pcre_stringpiece_unittest. Building the C++ wrapper
283     can be disabled by adding --disable-cpp to the "configure" command.
284 nigel 3
285 ph10 109 The command "make check" runs all the appropriate tests. Details of the PCRE
286     tests are given below in a separate section of this document.
287 nigel 75
288 ph10 109 You can use "make install" to install PCRE into live directories on your
289     system. The following are installed (file names are all relative to the
290     <prefix> that is set when "configure" is run):
291 nigel 77
292 ph10 109 Commands (bin):
293     pcretest
294     pcregrep
295 ph10 111 pcre-config
296 ph10 109
297     Libraries (lib):
298     libpcre
299     libpcreposix
300     libpcrecpp (if C++ support is enabled)
301    
302     Configuration information (lib/pkgconfig):
303     libpcre.pc
304 ph10 122 libpcrecpp.pc (if C++ support is enabled)
305 ph10 109
306     Header files (include):
307     pcre.h
308     pcreposix.h
309     pcre_scanner.h )
310     pcre_stringpiece.h ) if C++ support is enabled
311     pcrecpp.h )
312     pcrecpparg.h )
313    
314     Man pages (share/man/man{1,3}):
315     pcregrep.1
316     pcretest.1
317     pcre.3
318     pcre*.3 (lots more pages, all starting "pcre")
319    
320     HTML documentation (share/doc/pcre/html):
321     index.html
322     *.html (lots more pages, hyperlinked from index.html)
323    
324     Text file documentation (share/doc/pcre):
325     AUTHORS
326     COPYING
327     ChangeLog
328     LICENCE
329     NEWS
330     README
331     pcre.txt (a concatenation of the man(3) pages)
332     pcretest.txt the pcretest man page
333     pcregrep.txt the pcregrep man page
334    
335 ph10 111 Note that the pcredemo program that is built by "configure" is *not* installed
336 ph10 109 anywhere. It is a demonstration for programmers wanting to use PCRE.
337    
338 nigel 77 If you want to remove PCRE from your system, you can run "make uninstall".
339     This removes all the files that "make install" installed. However, it does not
340     remove any directories, because these are often shared with other programs.
341    
342    
343 ph10 122 Retrieving configuration information on Unix-like systems
344     ---------------------------------------------------------
345 nigel 75
346 ph10 109 Running "make install" installs the command pcre-config, which can be used to
347     recall information about the PCRE configuration and installation. For example:
348 nigel 37
349 nigel 43 pcre-config --version
350    
351     prints the version number, and
352    
353 nigel 75 pcre-config --libs
354 nigel 43
355     outputs information about where the library is installed. This command can be
356     included in makefiles for programs that use PCRE, saving the programmer from
357     having to remember too many details.
358    
359 nigel 75 The pkg-config command is another system for saving and retrieving information
360     about installed libraries. Instead of separate commands for each library, a
361     single command is used. For example:
362 nigel 43
363 nigel 75 pkg-config --cflags pcre
364    
365     The data is held in *.pc files that are installed in a directory called
366 ph10 109 <prefix>/lib/pkgconfig.
367 nigel 75
368    
369 nigel 63 Shared libraries on Unix-like systems
370     -------------------------------------
371 nigel 53
372 nigel 77 The default distribution builds PCRE as shared libraries and static libraries,
373     as long as the operating system supports shared libraries. Shared library
374     support relies on the "libtool" script which is built as part of the
375 nigel 53 "configure" process.
376 nigel 39
377 nigel 53 The libtool script is used to compile and link both shared and static
378     libraries. They are placed in a subdirectory called .libs when they are newly
379     built. The programs pcretest and pcregrep are built to use these uninstalled
380     libraries (by means of wrapper scripts in the case of shared libraries). When
381     you use "make install" to install shared libraries, pcregrep and pcretest are
382     automatically re-built to use the newly installed shared libraries before being
383 ph10 122 installed themselves. However, the versions left in the build directory still
384 nigel 53 use the uninstalled libraries.
385    
386     To build PCRE using static libraries only you must use --disable-shared when
387 nigel 75 configuring it. For example:
388 nigel 3
389 nigel 43 ./configure --prefix=/usr/gnu --disable-shared
390 nigel 41
391 nigel 53 Then run "make" in the usual way. Similarly, you can use --disable-static to
392     build only shared libraries.
393 nigel 41
394 nigel 43
395 ph10 122 Cross-compiling on Unix-like systems
396     ------------------------------------
397 nigel 63
398     You can specify CC and CFLAGS in the normal way to the "configure" command, in
399 ph10 128 order to cross-compile PCRE for some other host. However, you should NOT
400     specify --enable-rebuild-chartables, because if you do, the dftables.c source
401     file is compiled and run on the local host, in order to generate the inbuilt
402     character tables (the pcre_chartables.c file). This will probably not work,
403     because dftables.c needs to be compiled with the local compiler, not the cross
404     compiler.
405 nigel 63
406 ph10 128 When --enable-rebuild-chartables is not specified, pcre_chartables.c is created
407     by making a copy of pcre_chartables.c.dist, which is a default set of tables
408     that assumes ASCII code. Cross-compiling with the default tables should not be
409     a problem.
410 nigel 63
411 ph10 128 If you need to modify the character tables when cross-compiling, you should
412     move pcre_chartables.c.dist out of the way, then compile dftables.c by hand and
413     run it on the local host to make a new version of pcre_chartables.c.dist.
414     Then when you cross-compile PCRE this new version of the tables will be used.
415    
416    
417 nigel 87 Using HP's ANSI C++ compiler (aCC)
418     ----------------------------------
419    
420 nigel 93 Unless C++ support is disabled by specifying the "--disable-cpp" option of the
421 ph10 122 "configure" script, you must include the "-AA" option in the CXXFLAGS
422 nigel 87 environment variable in order for the C++ components to compile correctly.
423    
424     Also, note that the aCC compiler on PA-RISC platforms may have a defect whereby
425     needed libraries fail to get included when specifying the "-AA" compiler
426     option. If you experience unresolved symbols when linking the C++ programs,
427     use the workaround of specifying the following environment variable prior to
428     running the "configure" script:
429    
430     CXXLDFLAGS="-lstd_v2 -lCsup_v2"
431    
432 ph10 123
433 ph10 111 Making new tarballs
434     -------------------
435 nigel 87
436 ph10 123 The command "make dist" creates three PCRE tarballs, in tar.gz, tar.bz2, and
437     zip formats. However, if you have modified any of the man page sources in the
438     doc directory, you should first run the PrepareRelease script. This re-creates
439 ph10 111 the .txt and HTML forms of the documentation from the man pages.
440    
441    
442 nigel 41 Testing PCRE
443     ------------
444    
445 ph10 122 To test the basic PCRE library on a Unix system, run the RunTest script that is
446     created by the configuring process. There is also a script called RunGrepTest
447     that tests the options of the pcregrep command. If the C++ wrapper library is
448     built, three test programs called pcrecpp_unittest, pcre_scanner_unittest, and
449 ph10 109 pcre_stringpiece_unittest are also built.
450 nigel 41
451 ph10 109 Both the scripts and all the program tests are run if you obey "make check" or
452     "make test". For other systems, see the instructions in NON-UNIX-USE.
453 nigel 77
454     The RunTest script runs the pcretest test program (which is documented in its
455 ph10 122 own man page) on each of the testinput files in the testdata directory in
456 nigel 77 turn, and compares the output with the contents of the corresponding testoutput
457 nigel 93 files. A file called testtry is used to hold the main output from pcretest
458 nigel 75 (testsavedregex is also used as a working file). To run pcretest on just one of
459     the test files, give its number as an argument to RunTest, for example:
460 nigel 41
461 nigel 63 RunTest 2
462 nigel 3
463 ph10 109 The first test file can also be fed directly into the perltest.pl script to
464     check that Perl gives the same results. The only difference you should see is
465     in the first few lines, where the Perl version is given instead of the PCRE
466     version.
467 nigel 3
468 nigel 49 The second set of tests check pcre_fullinfo(), pcre_info(), pcre_study(),
469     pcre_copy_substring(), pcre_get_substring(), pcre_get_substring_list(), error
470     detection, and run-time flags that are specific to PCRE, as well as the POSIX
471 ph10 122 wrapper API. It also uses the debugging flags to check some of the internals of
472 nigel 49 pcre_compile().
473 nigel 7
474 nigel 49 If you build PCRE with a locale setting that is not the standard C locale, the
475     character tables may be different (see next paragraph). In some cases, this may
476     cause failures in the second set of tests. For example, in a locale where the
477     isprint() function yields TRUE for characters in the range 128-255, the use of
478     [:isascii:] inside a character class defines a different set of characters, and
479     this shows up in this test as a difference in the compiled code, which is being
480     listed for checking. Where the comparison test output contains [\x00-\x7f] the
481     test will contain [\x00-\xff], and similarly in some other cases. This is not a
482     bug in PCRE.
483    
484 nigel 63 The third set of tests checks pcre_maketables(), the facility for building a
485 nigel 25 set of character tables for a specific locale and using them instead of the
486 nigel 73 default tables. The tests make use of the "fr_FR" (French) locale. Before
487     running the test, the script checks for the presence of this locale by running
488     the "locale" command. If that command fails, or if it doesn't include "fr_FR"
489     in the list of available locales, the third test cannot be run, and a comment
490     is output to say why. If running this test produces instances of the error
491 nigel 25
492 nigel 73 ** Failed to set locale "fr_FR"
493 nigel 25
494     in the comparison output, it means that locale is not available on your system,
495     despite being listed by "locale". This does not mean that PCRE is broken.
496    
497 ph10 142 [If you are trying to run this test on Windows, you may be able to get it to
498 ph10 139 work by changing "fr_FR" to "french" everywhere it occurs.]
499    
500 nigel 63 The fourth test checks the UTF-8 support. It is not run automatically unless
501     PCRE is built with UTF-8 support. To do this you must set --enable-utf8 when
502     running "configure". This file can be also fed directly to the perltest script,
503     provided you are running Perl 5.8 or higher. (For Perl 5.6, a small patch,
504     commented in the script, can be be used.)
505 nigel 3
506 nigel 75 The fifth test checks error handling with UTF-8 encoding, and internal UTF-8
507     features of PCRE that are not relevant to Perl.
508 nigel 3
509 ph10 122 The sixth test checks the support for Unicode character properties. It it not
510     run automatically unless PCRE is built with Unicode property support. To to
511 nigel 77 this you must set --enable-unicode-properties when running "configure".
512 nigel 63
513 nigel 77 The seventh, eighth, and ninth tests check the pcre_dfa_exec() alternative
514     matching function, in non-UTF-8 mode, UTF-8 mode, and UTF-8 mode with Unicode
515     property support, respectively. The eighth and ninth tests are not run
516     automatically unless PCRE is build with the relevant support.
517 nigel 75
518 nigel 77
519 nigel 3 Character tables
520     ----------------
521    
522 ph10 122 For speed, PCRE uses four tables for manipulating and identifying characters
523     whose code point values are less than 256. The final argument of the
524     pcre_compile() function is a pointer to a block of memory containing the
525     concatenated tables. A call to pcre_maketables() can be used to generate a set
526     of tables in the current locale. If the final argument for pcre_compile() is
527     passed as NULL, a set of default tables that is built into the binary is used.
528 nigel 3
529 ph10 128 The source file called pcre_chartables.c contains the default set of tables. By
530     default, this is created as a copy of pcre_chartables.c.dist, which contains
531     tables for ASCII coding. However, if --enable-rebuild-chartables is specified
532     for ./configure, a different version of pcre_chartables.c is built by the
533     program dftables (compiled from dftables.c), which uses the ANSI C character
534     handling functions such as isalnum(), isalpha(), isupper(), islower(), etc. to
535     build the table sources. This means that the default C locale which is set for
536     your system will control the contents of these default tables. You can change
537     the default tables by editing pcre_chartables.c and then re-building PCRE. If
538     you do this, you should take care to ensure that the file does not get
539     automatically re-generated. The best way to do this is to move
540     pcre_chartables.c.dist out of the way and replace it with your customized
541     tables.
542 nigel 3
543 ph10 128 When the dftables program is run as a result of --enable-rebuild-chartables,
544     it uses the default C locale that is set on your system. It does not pay
545     attention to the LC_xxx environment variables. In other words, it uses the
546     system's default locale rather than whatever the compiling user happens to have
547     set. If you really do want to build a source set of character tables in a
548     locale that is specified by the LC_xxx variables, you can run the dftables
549     program by hand with the -L option. For example:
550    
551     ./dftables -L pcre_chartables.c.special
552    
553 nigel 25 The first two 256-byte tables provide lower casing and case flipping functions,
554     respectively. The next table consists of three 32-byte bit maps which identify
555     digits, "word" characters, and white space, respectively. These are used when
556 ph10 111 building 32-byte bit maps that represent character classes for code points less
557 ph10 109 than 256.
558 nigel 25
559     The final 256-byte table has bits indicating various character types, as
560 nigel 3 follows:
561    
562     1 white space character
563     2 letter
564     4 decimal digit
565     8 hexadecimal digit
566     16 alphanumeric or '_'
567     128 regular expression metacharacter or binary zero
568    
569     You should not alter the set of characters that contain the 128 bit, as that
570     will cause PCRE to malfunction.
571    
572    
573 ph10 109 File manifest
574     -------------
575 nigel 3
576 nigel 41 The distribution should contain the following files:
577 nigel 3
578 ph10 109 (A) Source files of the PCRE library functions and their headers:
579 nigel 3
580 ph10 128 dftables.c auxiliary program for building pcre_chartables.c
581     when --enable-rebuild-chartables is specified
582 ph10 111
583 ph10 128 pcre_chartables.c.dist a default set of character tables that assume ASCII
584     coding; used, unless --enable-rebuild-chartables is
585     specified, by copying to pcre_chartables.c
586 ph10 111
587 ph10 128 pcreposix.c )
588     pcre_compile.c )
589     pcre_config.c )
590     pcre_dfa_exec.c )
591     pcre_exec.c )
592     pcre_fullinfo.c )
593     pcre_get.c ) sources for the functions in the library,
594     pcre_globals.c ) and some internal functions that they use
595     pcre_info.c )
596     pcre_maketables.c )
597     pcre_newline.c )
598     pcre_ord2utf8.c )
599     pcre_refcount.c )
600     pcre_study.c )
601     pcre_tables.c )
602     pcre_try_flipped.c )
603     pcre_ucp_searchfuncs.c )
604     pcre_valid_utf8.c )
605     pcre_version.c )
606     pcre_xclass.c )
607     pcre_printint.src ) debugging function that is #included in pcretest,
608     ) and can also be #included in pcre_compile()
609     pcre.h.in template for pcre.h when built by "configure"
610     pcreposix.h header for the external POSIX wrapper API
611     pcre_internal.h header for internal use
612     ucp.h ) headers concerned with
613     ucpinternal.h ) Unicode property handling
614     ucptable.h ) (this one is the data table)
615 ph10 111
616 ph10 128 config.h.in template for config.h, which is built by "configure"
617 ph10 111
618 ph10 128 pcrecpp.h public header file for the C++ wrapper
619     pcrecpparg.h.in template for another C++ header file
620     pcre_scanner.h public header file for C++ scanner functions
621     pcrecpp.cc )
622     pcre_scanner.cc ) source for the C++ wrapper library
623 ph10 111
624 ph10 128 pcre_stringpiece.h.in template for pcre_stringpiece.h, the header for the
625     C++ stringpiece functions
626     pcre_stringpiece.cc source for the C++ stringpiece functions
627    
628 ph10 109 (B) Source files for programs that use PCRE:
629 nigel 75
630 ph10 128 pcredemo.c simple demonstration of coding calls to PCRE
631     pcregrep.c source of a grep utility that uses PCRE
632     pcretest.c comprehensive test program
633 ph10 111
634     (C) Auxiliary files:
635    
636 ph10 128 132html script to turn "man" pages into HTML
637     AUTHORS information about the author of PCRE
638     ChangeLog log of changes to the code
639     CleanTxt script to clean nroff output for txt man pages
640     Detrail script to remove trailing spaces
641     HACKING some notes about the internals of PCRE
642     INSTALL generic installation instructions
643     LICENCE conditions for the use of PCRE
644     COPYING the same, using GNU's standard name
645     Makefile.in ) template for Unix Makefile, which is built by
646     ) "configure"
647     Makefile.am ) the automake input that was used to create
648     ) Makefile.in
649     NEWS important changes in this release
650     NON-UNIX-USE notes on building PCRE on non-Unix systems
651     PrepareRelease script to make preparations for "make dist"
652     README this file
653 ph10 138 RunTest a Unix shell script for running tests
654     RunGrepTest a Unix shell script for pcregrep tests
655 ph10 128 aclocal.m4 m4 macros (generated by "aclocal")
656     config.guess ) files used by libtool,
657     config.sub ) used only when building a shared library
658     configure a configuring shell script (built by autoconf)
659     configure.ac ) the autoconf input that was used to build
660     ) "configure" and config.h
661     depcomp ) script to find program dependencies, generated by
662     ) automake
663     doc/*.3 man page sources for the PCRE functions
664     doc/*.1 man page sources for pcregrep and pcretest
665     doc/index.html.src the base HTML page
666     doc/html/* HTML documentation
667     doc/pcre.txt plain text version of the man pages
668     doc/pcretest.txt plain text documentation of test program
669     doc/perltest.txt plain text documentation of Perl test program
670     install-sh a shell script for installing files
671     libpcre.pc.in template for libpcre.pc for pkg-config
672     libpcrecpp.pc.in template for libpcrecpp.pc for pkg-config
673     ltmain.sh file used to build a libtool script
674     missing ) common stub for a few missing GNU programs while
675     ) installing, generated by automake
676     mkinstalldirs script for making install directories
677     perltest.pl Perl test program
678     pcre-config.in source of script which retains PCRE information
679 ph10 111 pcrecpp_unittest.cc )
680     pcre_scanner_unittest.cc ) test programs for the C++ wrapper
681     pcre_stringpiece_unittest.cc )
682 ph10 128 testdata/testinput* test data for main library tests
683     testdata/testoutput* expected test results
684     testdata/grep* input and output for pcregrep tests
685 ph10 111
686 ph10 109 (D) Auxiliary files for cmake support
687 nigel 3
688 ph10 109 CMakeLists.txt
689 ph10 111 config-cmake.h.in
690 nigel 29
691 ph10 109 (E) Auxiliary files for VPASCAL
692 nigel 29
693 nigel 63 makevp.bat
694 ph10 135 makevp_c.txt
695     makevp_l.txt
696 ph10 111 pcregexp.pas
697    
698     (F) Auxiliary files for building PCRE "by hand"
699    
700 ph10 128 pcre.h.generic ) a version of the public PCRE header file
701     ) for use in non-"configure" environments
702     config.h.generic ) a version of config.h for use in non-"configure"
703     ) environments
704 ph10 111
705 ph10 109 (F) Miscellaneous
706 nigel 63
707 ph10 109 RunTest.bat a script for running tests under Windows
708    
709 nigel 77 Philip Hazel
710     Email local part: ph10
711     Email domain: cam.ac.uk
712 ph10 138 Last updated: 29 March 2007

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