/[pcre]/code/trunk/README
ViewVC logotype

Diff of /code/trunk/README

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 7 by nigel, Sat Feb 24 21:38:09 2007 UTC revision 392 by ph10, Tue Mar 17 21:30:30 2009 UTC
# Line 1  Line 1 
1  README file for PCRE (Perl-compatible regular expressions)  README file for PCRE (Perl-compatible regular expression library)
2  ----------------------------------------------------------  -----------------------------------------------------------------
3    
4  The distribution should contain the following files:  The latest release of PCRE is always available in three alternative formats
5    from:
6    
7    ChangeLog         log of changes to the code    ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.gz
8    Makefile          for building PCRE    ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.bz2
9    Performance       notes on performance    ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.zip
10    README            this file  
11    Tech.Notes        notes on the encoding  There is a mailing list for discussion about the development of PCRE at
12    pcre.3            man page for the functions  
13    pcreposix.3       man page for the POSIX wrapper API    pcre-dev@exim.org
14    maketables.c      auxiliary program for building chartables.c  
15    study.c           ) source of  Please read the NEWS file if you are upgrading from a previous release.
16    pcre.c            )   the functions  The contents of this README file are:
17    pcreposix.c       )  
18    pcre.h            header for the external API    The PCRE APIs
19    pcreposix.h       header for the external POSIX wrapper API    Documentation for PCRE
20    internal.h        header for internal use    Contributions by users of PCRE
21    pcretest.c        test program    Building PCRE on non-Unix systems
22    pgrep.1           man page for pgrep    Building PCRE on Unix-like systems
23    pgrep.c           source of a grep utility that uses PCRE    Retrieving configuration information on Unix-like systems
24    perltest          Perl test program    Shared libraries on Unix-like systems
25    testinput         test data, compatible with Perl    Cross-compiling on Unix-like systems
26    testinput2        test data for error messages and non-Perl things    Using HP's ANSI C++ compiler (aCC)
27    testoutput        test results corresponding to testinput    Making new tarballs
28    testoutput2       test results corresponding to testinput2    Testing PCRE
29      Character tables
30  To build PCRE, edit Makefile for your system (it is a fairly simple make file)    File manifest
31  and then run it. It builds a two libraries called libpcre.a and libpcreposix.a,  
32  a test program called pcretest, and the pgrep command.  
33    The PCRE APIs
34  To test PCRE, run pcretest on the file testinput, and compare the output with  -------------
35  the contents of testoutput. There should be no differences. For example:  
36    PCRE is written in C, and it has its own API. The distribution also includes a
37    pcretest testinput some.file  set of C++ wrapper functions (see the pcrecpp man page for details), courtesy
38    diff some.file testoutput  of Google Inc.
39    
40  Do the same with testinput2, comparing the output with testoutput2, but this  In addition, there is a set of C wrapper functions that are based on the POSIX
41  time using the -i flag for pcretest, i.e.  regular expression API (see the pcreposix man page). These end up in the
42    library called libpcreposix. Note that this just provides a POSIX calling
43    pcretest -i testinput2 some.file  interface to PCRE; the regular expressions themselves still follow Perl syntax
44    diff some.file testoutput2  and semantics. The POSIX API is restricted, and does not give full access to
45    all of PCRE's facilities.
46  The make target "runtest" runs both these tests, using the file "testtry" to  
47  store the intermediate output, deleting it at the end if all goes well.  The header file for the POSIX-style functions is called pcreposix.h. The
48    official POSIX name is regex.h, but I did not want to risk possible problems
49  There are two sets of tests because the first set can also be fed directly into  with existing files of that name by distributing it that way. To use PCRE with
50  the perltest program to check that Perl gives the same results. The second set  an existing program that uses the POSIX API, pcreposix.h will have to be
51  of tests check pcre_info(), pcre_study(), error detection and run-time flags  renamed or pointed at by a link.
52  that are specific to PCRE, as well as the POSIX wrapper API.  
53    If you are using the POSIX interface to PCRE and there is already a POSIX regex
54  To install PCRE, copy libpcre.a to any suitable library directory (e.g.  library installed on your system, as well as worrying about the regex.h header
55  /usr/local/lib), pcre.h to any suitable include directory (e.g.  file (as mentioned above), you must also take care when linking programs to
56  /usr/local/include), and pcre.3 to any suitable man directory (e.g.  ensure that they link with PCRE's libpcreposix library. Otherwise they may pick
57  /usr/local/man/man3).  up the POSIX functions of the same name from the other library.
58    
59  To install the pgrep command, copy it to any suitable binary directory, (e.g.  One way of avoiding this confusion is to compile PCRE with the addition of
60  /usr/local/bin) and pgrep.1 to any suitable man directory (e.g.  -Dregcomp=PCREregcomp (and similarly for the other POSIX functions) to the
61  /usr/local/man/man1).  compiler flags (CFLAGS if you are using "configure" -- see below). This has the
62    effect of renaming the functions so that the names no longer clash. Of course,
63  PCRE has its own native API, but a set of "wrapper" functions that are based on  you have to do the same thing for your applications, or write them using the
64  the POSIX API are also supplied in the library libpcreposix.a. Note that this  new names.
65  just provides a POSIX calling interface to PCRE: the regular expressions  
66  themselves still follow Perl syntax and semantics. The header file  
67  for the POSIX-style functions is called pcreposix.h. The official POSIX name is  Documentation for PCRE
68  regex.h, but I didn't want to risk possible problems with existing files of  ----------------------
69  that name by distributing it that way. To use it with an existing program that  
70  uses the POSIX API it will have to be renamed or pointed at by a link.  If you install PCRE in the normal way on a Unix-like system, you will end up
71    with a set of man pages whose names all start with "pcre". The one that is just
72    called "pcre" lists all the others. In addition to these man pages, the PCRE
73    documentation is supplied in two other forms:
74    
75      1. There are files called doc/pcre.txt, doc/pcregrep.txt, and
76         doc/pcretest.txt in the source distribution. The first of these is a
77         concatenation of the text forms of all the section 3 man pages except
78         those that summarize individual functions. The other two are the text
79         forms of the section 1 man pages for the pcregrep and pcretest commands.
80         These text forms are provided for ease of scanning with text editors or
81         similar tools. They are installed in <prefix>/share/doc/pcre, where
82         <prefix> is the installation prefix (defaulting to /usr/local).
83    
84      2. A set of files containing all the documentation in HTML form, hyperlinked
85         in various ways, and rooted in a file called index.html, is distributed in
86         doc/html and installed in <prefix>/share/doc/pcre/html.
87    
88    
89    Contributions by users of PCRE
90    ------------------------------
91    
92    You can find contributions from PCRE users in the directory
93    
94      ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/Contrib
95    
96    There is a README file giving brief descriptions of what they are. Some are
97    complete in themselves; others are pointers to URLs containing relevant files.
98    Some of this material is likely to be well out-of-date. Several of the earlier
99    contributions provided support for compiling PCRE on various flavours of
100    Windows (I myself do not use Windows). Nowadays there is more Windows support
101    in the standard distribution, so these contibutions have been archived.
102    
103    
104    Building PCRE on non-Unix systems
105    ---------------------------------
106    
107    For a non-Unix system, please read the comments in the file NON-UNIX-USE,
108    though if your system supports the use of "configure" and "make" you may be
109    able to build PCRE in the same way as for Unix-like systems. PCRE can also be
110    configured in many platform environments using the GUI facility of CMake's
111    CMakeSetup. It creates Makefiles, solution files, etc.
112    
113    PCRE has been compiled on many different operating systems. It should be
114    straightforward to build PCRE on any system that has a Standard C compiler and
115    library, because it uses only Standard C functions.
116    
117    
118    Building PCRE on Unix-like systems
119    ----------------------------------
120    
121    If you are using HP's ANSI C++ compiler (aCC), please see the special note
122    in the section entitled "Using HP's ANSI C++ compiler (aCC)" below.
123    
124    The following instructions assume the use of the widely used "configure, make,
125    make install" process. There is also support for CMake in the PCRE
126    distribution; there are some comments about using CMake in the NON-UNIX-USE
127    file, though it can also be used in Unix-like systems.
128    
129    To build PCRE on a Unix-like system, first run the "configure" command from the
130    PCRE distribution directory, with your current directory set to the directory
131    where you want the files to be created. This command is a standard GNU
132    "autoconf" configuration script, for which generic instructions are supplied in
133    the file INSTALL.
134    
135    Most commonly, people build PCRE within its own distribution directory, and in
136    this case, on many systems, just running "./configure" is sufficient. However,
137    the usual methods of changing standard defaults are available. For example:
138    
139    CFLAGS='-O2 -Wall' ./configure --prefix=/opt/local
140    
141    specifies that the C compiler should be run with the flags '-O2 -Wall' instead
142    of the default, and that "make install" should install PCRE under /opt/local
143    instead of the default /usr/local.
144    
145    If you want to build in a different directory, just run "configure" with that
146    directory as current. For example, suppose you have unpacked the PCRE source
147    into /source/pcre/pcre-xxx, but you want to build it in /build/pcre/pcre-xxx:
148    
149    cd /build/pcre/pcre-xxx
150    /source/pcre/pcre-xxx/configure
151    
152    PCRE is written in C and is normally compiled as a C library. However, it is
153    possible to build it as a C++ library, though the provided building apparatus
154    does not have any features to support this.
155    
156    There are some optional features that can be included or omitted from the PCRE
157    library. You can read more about them in the pcrebuild man page.
158    
159    . If you want to suppress the building of the C++ wrapper library, you can add
160      --disable-cpp to the "configure" command. Otherwise, when "configure" is run,
161      it will try to find a C++ compiler and C++ header files, and if it succeeds,
162      it will try to build the C++ wrapper.
163    
164    . If you want to make use of the support for UTF-8 Unicode character strings in
165      PCRE, you must add --enable-utf8 to the "configure" command. Without it, the
166      code for handling UTF-8 is not included in the library. Even when included,
167      it still has to be enabled by an option at run time. When PCRE is compiled
168      with this option, its input can only either be ASCII or UTF-8, even when
169      running on EBCDIC platforms. It is not possible to use both --enable-utf8 and
170      --enable-ebcdic at the same time.
171    
172    . If, in addition to support for UTF-8 character strings, you want to include
173      support for the \P, \p, and \X sequences that recognize Unicode character
174      properties, you must add --enable-unicode-properties to the "configure"
175      command. This adds about 30K to the size of the library (in the form of a
176      property table); only the basic two-letter properties such as Lu are
177      supported.
178    
179    . You can build PCRE to recognize either CR or LF or the sequence CRLF or any
180      of the preceding, or any of the Unicode newline sequences as indicating the
181      end of a line. Whatever you specify at build time is the default; the caller
182      of PCRE can change the selection at run time. The default newline indicator
183      is a single LF character (the Unix standard). You can specify the default
184      newline indicator by adding --enable-newline-is-cr or --enable-newline-is-lf
185      or --enable-newline-is-crlf or --enable-newline-is-anycrlf or
186      --enable-newline-is-any to the "configure" command, respectively.
187    
188      If you specify --enable-newline-is-cr or --enable-newline-is-crlf, some of
189      the standard tests will fail, because the lines in the test files end with
190      LF. Even if the files are edited to change the line endings, there are likely
191      to be some failures. With --enable-newline-is-anycrlf or
192      --enable-newline-is-any, many tests should succeed, but there may be some
193      failures.
194    
195    . By default, the sequence \R in a pattern matches any Unicode line ending
196      sequence. This is independent of the option specifying what PCRE considers to
197      be the end of a line (see above). However, the caller of PCRE can restrict \R
198      to match only CR, LF, or CRLF. You can make this the default by adding
199      --enable-bsr-anycrlf to the "configure" command (bsr = "backslash R").
200    
201    . When called via the POSIX interface, PCRE uses malloc() to get additional
202      storage for processing capturing parentheses if there are more than 10 of
203      them in a pattern. You can increase this threshold by setting, for example,
204    
205      --with-posix-malloc-threshold=20
206    
207      on the "configure" command.
208    
209    . PCRE has a counter that can be set to limit the amount of resources it uses.
210      If the limit is exceeded during a match, the match fails. The default is ten
211      million. You can change the default by setting, for example,
212    
213      --with-match-limit=500000
214    
215      on the "configure" command. This is just the default; individual calls to
216      pcre_exec() can supply their own value. There is more discussion on the
217      pcreapi man page.
218    
219    . There is a separate counter that limits the depth of recursive function calls
220      during a matching process. This also has a default of ten million, which is
221      essentially "unlimited". You can change the default by setting, for example,
222    
223      --with-match-limit-recursion=500000
224    
225      Recursive function calls use up the runtime stack; running out of stack can
226      cause programs to crash in strange ways. There is a discussion about stack
227      sizes in the pcrestack man page.
228    
229    . The default maximum compiled pattern size is around 64K. You can increase
230      this by adding --with-link-size=3 to the "configure" command. You can
231      increase it even more by setting --with-link-size=4, but this is unlikely
232      ever to be necessary. Increasing the internal link size will reduce
233      performance.
234    
235    . You can build PCRE so that its internal match() function that is called from
236      pcre_exec() does not call itself recursively. Instead, it uses memory blocks
237      obtained from the heap via the special functions pcre_stack_malloc() and
238      pcre_stack_free() to save data that would otherwise be saved on the stack. To
239      build PCRE like this, use
240    
241      --disable-stack-for-recursion
242    
243      on the "configure" command. PCRE runs more slowly in this mode, but it may be
244      necessary in environments with limited stack sizes. This applies only to the
245      pcre_exec() function; it does not apply to pcre_dfa_exec(), which does not
246      use deeply nested recursion. There is a discussion about stack sizes in the
247      pcrestack man page.
248    
249    . For speed, PCRE uses four tables for manipulating and identifying characters
250      whose code point values are less than 256. By default, it uses a set of
251      tables for ASCII encoding that is part of the distribution. If you specify
252    
253      --enable-rebuild-chartables
254    
255      a program called dftables is compiled and run in the default C locale when
256      you obey "make". It builds a source file called pcre_chartables.c. If you do
257      not specify this option, pcre_chartables.c is created as a copy of
258      pcre_chartables.c.dist. See "Character tables" below for further information.
259    
260    . It is possible to compile PCRE for use on systems that use EBCDIC as their
261      character code (as opposed to ASCII) by specifying
262    
263      --enable-ebcdic
264    
265      This automatically implies --enable-rebuild-chartables (see above). However,
266      when PCRE is built this way, it always operates in EBCDIC. It cannot support
267      both EBCDIC and UTF-8.
268    
269    . It is possible to compile pcregrep to use libz and/or libbz2, in order to
270      read .gz and .bz2 files (respectively), by specifying one or both of
271    
272      --enable-pcregrep-libz
273      --enable-pcregrep-libbz2
274    
275      Of course, the relevant libraries must be installed on your system.
276    
277    . It is possible to compile pcretest so that it links with the libreadline
278      library, by specifying
279    
280      --enable-pcretest-libreadline
281    
282      If this is done, when pcretest's input is from a terminal, it reads it using
283      the readline() function. This provides line-editing and history facilities.
284      Note that libreadline is GPL-licenced, so if you distribute a binary of
285      pcretest linked in this way, there may be licensing issues.
286    
287      Setting this option causes the -lreadline option to be added to the pcretest
288      build. In many operating environments with a sytem-installed readline
289      library this is sufficient. However, in some environments (e.g. if an
290      unmodified distribution version of readline is in use), it may be necessary
291      to specify something like LIBS="-lncurses" as well. This is because, to quote
292      the readline INSTALL, "Readline uses the termcap functions, but does not link
293      with the termcap or curses library itself, allowing applications which link
294      with readline the to choose an appropriate library." If you get error
295      messages about missing functions tgetstr, tgetent, tputs, tgetflag, or tgoto,
296      this is the problem, and linking with the ncurses library should fix it.
297    
298    The "configure" script builds the following files for the basic C library:
299    
300    . Makefile is the makefile that builds the library
301    . config.h contains build-time configuration options for the library
302    . pcre.h is the public PCRE header file
303    . pcre-config is a script that shows the settings of "configure" options
304    . libpcre.pc is data for the pkg-config command
305    . libtool is a script that builds shared and/or static libraries
306    . RunTest is a script for running tests on the basic C library
307    . RunGrepTest is a script for running tests on the pcregrep command
308    
309    Versions of config.h and pcre.h are distributed in the PCRE tarballs under
310    the names config.h.generic and pcre.h.generic. These are provided for the
311    benefit of those who have to built PCRE without the benefit of "configure". If
312    you use "configure", the .generic versions are not used.
313    
314    If a C++ compiler is found, the following files are also built:
315    
316    . libpcrecpp.pc is data for the pkg-config command
317    . pcrecpparg.h is a header file for programs that call PCRE via the C++ wrapper
318    . pcre_stringpiece.h is the header for the C++ "stringpiece" functions
319    
320    The "configure" script also creates config.status, which is an executable
321    script that can be run to recreate the configuration, and config.log, which
322    contains compiler output from tests that "configure" runs.
323    
324    Once "configure" has run, you can run "make". It builds two libraries, called
325    libpcre and libpcreposix, a test program called pcretest, and the pcregrep
326    command. If a C++ compiler was found on your system, "make" also builds the C++
327    wrapper library, which is called libpcrecpp, and some test programs called
328    pcrecpp_unittest, pcre_scanner_unittest, and pcre_stringpiece_unittest.
329    Building the C++ wrapper can be disabled by adding --disable-cpp to the
330    "configure" command.
331    
332    The command "make check" runs all the appropriate tests. Details of the PCRE
333    tests are given below in a separate section of this document.
334    
335    You can use "make install" to install PCRE into live directories on your
336    system. The following are installed (file names are all relative to the
337    <prefix> that is set when "configure" is run):
338    
339      Commands (bin):
340        pcretest
341        pcregrep
342        pcre-config
343    
344      Libraries (lib):
345        libpcre
346        libpcreposix
347        libpcrecpp (if C++ support is enabled)
348    
349      Configuration information (lib/pkgconfig):
350        libpcre.pc
351        libpcrecpp.pc (if C++ support is enabled)
352    
353      Header files (include):
354        pcre.h
355        pcreposix.h
356        pcre_scanner.h      )
357        pcre_stringpiece.h  ) if C++ support is enabled
358        pcrecpp.h           )
359        pcrecpparg.h        )
360    
361      Man pages (share/man/man{1,3}):
362        pcregrep.1
363        pcretest.1
364        pcre.3
365        pcre*.3 (lots more pages, all starting "pcre")
366    
367      HTML documentation (share/doc/pcre/html):
368        index.html
369        *.html (lots more pages, hyperlinked from index.html)
370    
371      Text file documentation (share/doc/pcre):
372        AUTHORS
373        COPYING
374        ChangeLog
375        LICENCE
376        NEWS
377        README
378        pcre.txt       (a concatenation of the man(3) pages)
379        pcretest.txt   the pcretest man page
380        pcregrep.txt   the pcregrep man page
381    
382    If you want to remove PCRE from your system, you can run "make uninstall".
383    This removes all the files that "make install" installed. However, it does not
384    remove any directories, because these are often shared with other programs.
385    
386    
387    Retrieving configuration information on Unix-like systems
388    ---------------------------------------------------------
389    
390    Running "make install" installs the command pcre-config, which can be used to
391    recall information about the PCRE configuration and installation. For example:
392    
393      pcre-config --version
394    
395    prints the version number, and
396    
397      pcre-config --libs
398    
399    outputs information about where the library is installed. This command can be
400    included in makefiles for programs that use PCRE, saving the programmer from
401    having to remember too many details.
402    
403    The pkg-config command is another system for saving and retrieving information
404    about installed libraries. Instead of separate commands for each library, a
405    single command is used. For example:
406    
407      pkg-config --cflags pcre
408    
409    The data is held in *.pc files that are installed in a directory called
410    <prefix>/lib/pkgconfig.
411    
412    
413    Shared libraries on Unix-like systems
414    -------------------------------------
415    
416    The default distribution builds PCRE as shared libraries and static libraries,
417    as long as the operating system supports shared libraries. Shared library
418    support relies on the "libtool" script which is built as part of the
419    "configure" process.
420    
421    The libtool script is used to compile and link both shared and static
422    libraries. They are placed in a subdirectory called .libs when they are newly
423    built. The programs pcretest and pcregrep are built to use these uninstalled
424    libraries (by means of wrapper scripts in the case of shared libraries). When
425    you use "make install" to install shared libraries, pcregrep and pcretest are
426    automatically re-built to use the newly installed shared libraries before being
427    installed themselves. However, the versions left in the build directory still
428    use the uninstalled libraries.
429    
430    To build PCRE using static libraries only you must use --disable-shared when
431    configuring it. For example:
432    
433    ./configure --prefix=/usr/gnu --disable-shared
434    
435    Then run "make" in the usual way. Similarly, you can use --disable-static to
436    build only shared libraries.
437    
438    
439    Cross-compiling on Unix-like systems
440    ------------------------------------
441    
442    You can specify CC and CFLAGS in the normal way to the "configure" command, in
443    order to cross-compile PCRE for some other host. However, you should NOT
444    specify --enable-rebuild-chartables, because if you do, the dftables.c source
445    file is compiled and run on the local host, in order to generate the inbuilt
446    character tables (the pcre_chartables.c file). This will probably not work,
447    because dftables.c needs to be compiled with the local compiler, not the cross
448    compiler.
449    
450    When --enable-rebuild-chartables is not specified, pcre_chartables.c is created
451    by making a copy of pcre_chartables.c.dist, which is a default set of tables
452    that assumes ASCII code. Cross-compiling with the default tables should not be
453    a problem.
454    
455    If you need to modify the character tables when cross-compiling, you should
456    move pcre_chartables.c.dist out of the way, then compile dftables.c by hand and
457    run it on the local host to make a new version of pcre_chartables.c.dist.
458    Then when you cross-compile PCRE this new version of the tables will be used.
459    
460    
461    Using HP's ANSI C++ compiler (aCC)
462    ----------------------------------
463    
464    Unless C++ support is disabled by specifying the "--disable-cpp" option of the
465    "configure" script, you must include the "-AA" option in the CXXFLAGS
466    environment variable in order for the C++ components to compile correctly.
467    
468    Also, note that the aCC compiler on PA-RISC platforms may have a defect whereby
469    needed libraries fail to get included when specifying the "-AA" compiler
470    option. If you experience unresolved symbols when linking the C++ programs,
471    use the workaround of specifying the following environment variable prior to
472    running the "configure" script:
473    
474      CXXLDFLAGS="-lstd_v2 -lCsup_v2"
475    
476    
477    Making new tarballs
478    -------------------
479    
480    The command "make dist" creates three PCRE tarballs, in tar.gz, tar.bz2, and
481    zip formats. The command "make distcheck" does the same, but then does a trial
482    build of the new distribution to ensure that it works.
483    
484    If you have modified any of the man page sources in the doc directory, you
485    should first run the PrepareRelease script before making a distribution. This
486    script creates the .txt and HTML forms of the documentation from the man pages.
487    
488    
489    Testing PCRE
490    ------------
491    
492    To test the basic PCRE library on a Unix system, run the RunTest script that is
493    created by the configuring process. There is also a script called RunGrepTest
494    that tests the options of the pcregrep command. If the C++ wrapper library is
495    built, three test programs called pcrecpp_unittest, pcre_scanner_unittest, and
496    pcre_stringpiece_unittest are also built.
497    
498    Both the scripts and all the program tests are run if you obey "make check" or
499    "make test". For other systems, see the instructions in NON-UNIX-USE.
500    
501    The RunTest script runs the pcretest test program (which is documented in its
502    own man page) on each of the testinput files in the testdata directory in
503    turn, and compares the output with the contents of the corresponding testoutput
504    files. A file called testtry is used to hold the main output from pcretest
505    (testsavedregex is also used as a working file). To run pcretest on just one of
506    the test files, give its number as an argument to RunTest, for example:
507    
508      RunTest 2
509    
510    The first test file can also be fed directly into the perltest.pl script to
511    check that Perl gives the same results. The only difference you should see is
512    in the first few lines, where the Perl version is given instead of the PCRE
513    version.
514    
515    The second set of tests check pcre_fullinfo(), pcre_info(), pcre_study(),
516    pcre_copy_substring(), pcre_get_substring(), pcre_get_substring_list(), error
517    detection, and run-time flags that are specific to PCRE, as well as the POSIX
518    wrapper API. It also uses the debugging flags to check some of the internals of
519    pcre_compile().
520    
521    If you build PCRE with a locale setting that is not the standard C locale, the
522    character tables may be different (see next paragraph). In some cases, this may
523    cause failures in the second set of tests. For example, in a locale where the
524    isprint() function yields TRUE for characters in the range 128-255, the use of
525    [:isascii:] inside a character class defines a different set of characters, and
526    this shows up in this test as a difference in the compiled code, which is being
527    listed for checking. Where the comparison test output contains [\x00-\x7f] the
528    test will contain [\x00-\xff], and similarly in some other cases. This is not a
529    bug in PCRE.
530    
531    The third set of tests checks pcre_maketables(), the facility for building a
532    set of character tables for a specific locale and using them instead of the
533    default tables. The tests make use of the "fr_FR" (French) locale. Before
534    running the test, the script checks for the presence of this locale by running
535    the "locale" command. If that command fails, or if it doesn't include "fr_FR"
536    in the list of available locales, the third test cannot be run, and a comment
537    is output to say why. If running this test produces instances of the error
538    
539      ** Failed to set locale "fr_FR"
540    
541    in the comparison output, it means that locale is not available on your system,
542    despite being listed by "locale". This does not mean that PCRE is broken.
543    
544    [If you are trying to run this test on Windows, you may be able to get it to
545    work by changing "fr_FR" to "french" everywhere it occurs. Alternatively, use
546    RunTest.bat. The version of RunTest.bat included with PCRE 7.4 and above uses
547    Windows versions of test 2. More info on using RunTest.bat is included in the
548    document entitled NON-UNIX-USE.]
549    
550    The fourth test checks the UTF-8 support. It is not run automatically unless
551    PCRE is built with UTF-8 support. To do this you must set --enable-utf8 when
552    running "configure". This file can be also fed directly to the perltest script,
553    provided you are running Perl 5.8 or higher. (For Perl 5.6, a small patch,
554    commented in the script, can be be used.)
555    
556    The fifth test checks error handling with UTF-8 encoding, and internal UTF-8
557    features of PCRE that are not relevant to Perl.
558    
559    The sixth test checks the support for Unicode character properties. It it not
560    run automatically unless PCRE is built with Unicode property support. To to
561    this you must set --enable-unicode-properties when running "configure".
562    
563    The seventh, eighth, and ninth tests check the pcre_dfa_exec() alternative
564    matching function, in non-UTF-8 mode, UTF-8 mode, and UTF-8 mode with Unicode
565    property support, respectively. The eighth and ninth tests are not run
566    automatically unless PCRE is build with the relevant support.
567    
568    
569  Character tables  Character tables
570  ----------------  ----------------
571    
572  PCRE uses four tables for manipulating and identifying characters. These are  For speed, PCRE uses four tables for manipulating and identifying characters
573  compiled from a source file called chartables.c. This is not supplied in  whose code point values are less than 256. The final argument of the
574  the distribution, but is built by the program maketables (compiled from  pcre_compile() function is a pointer to a block of memory containing the
575  maketables.c), which uses the ANSI C character handling functions such as  concatenated tables. A call to pcre_maketables() can be used to generate a set
576  isalnum(), isalpha(), isupper(), islower(), etc. to build the table sources.  of tables in the current locale. If the final argument for pcre_compile() is
577  This means that the default C locale set in your system may affect the contents  passed as NULL, a set of default tables that is built into the binary is used.
578  of the tables. You can change the tables by editing chartables.c and then  
579  re-building PCRE. If you do this, you should probably also edit Makefile to  The source file called pcre_chartables.c contains the default set of tables. By
580  ensure that the file doesn't ever get re-generated.  default, this is created as a copy of pcre_chartables.c.dist, which contains
581    tables for ASCII coding. However, if --enable-rebuild-chartables is specified
582  The first two tables pcre_lcc[] and pcre_fcc[] provide lower casing and a  for ./configure, a different version of pcre_chartables.c is built by the
583  case flipping functions, respectively. The pcre_cbits[] table consists of four  program dftables (compiled from dftables.c), which uses the ANSI C character
584  32-byte bit maps which identify digits, letters, "word" characters, and white  handling functions such as isalnum(), isalpha(), isupper(), islower(), etc. to
585  space, respectively. These are used when building 32-byte bit maps that  build the table sources. This means that the default C locale which is set for
586  represent character classes.  your system will control the contents of these default tables. You can change
587    the default tables by editing pcre_chartables.c and then re-building PCRE. If
588    you do this, you should take care to ensure that the file does not get
589    automatically re-generated. The best way to do this is to move
590    pcre_chartables.c.dist out of the way and replace it with your customized
591    tables.
592    
593    When the dftables program is run as a result of --enable-rebuild-chartables,
594    it uses the default C locale that is set on your system. It does not pay
595    attention to the LC_xxx environment variables. In other words, it uses the
596    system's default locale rather than whatever the compiling user happens to have
597    set. If you really do want to build a source set of character tables in a
598    locale that is specified by the LC_xxx variables, you can run the dftables
599    program by hand with the -L option. For example:
600    
601      ./dftables -L pcre_chartables.c.special
602    
603    The first two 256-byte tables provide lower casing and case flipping functions,
604    respectively. The next table consists of three 32-byte bit maps which identify
605    digits, "word" characters, and white space, respectively. These are used when
606    building 32-byte bit maps that represent character classes for code points less
607    than 256.
608    
609  The pcre_ctypes[] table has bits indicating various character types, as  The final 256-byte table has bits indicating various character types, as
610  follows:  follows:
611    
612      1   white space character      1   white space character
# Line 102  You should not alter the set of characte Line 620  You should not alter the set of characte
620  will cause PCRE to malfunction.  will cause PCRE to malfunction.
621    
622    
623  The pcretest program  File manifest
624  --------------------  -------------
625    
626    The distribution should contain the following files:
627    
628  This program is intended for testing PCRE, but it can also be used for  (A) Source files of the PCRE library functions and their headers:
 experimenting with regular expressions.  
629    
630  If it is given two filename arguments, it reads from the first and writes to    dftables.c              auxiliary program for building pcre_chartables.c
631  the second. If it is given only one filename argument, it reads from that file                              when --enable-rebuild-chartables is specified
 and writes to stdout. Otherwise, it reads from stdin and writes to stdout, and  
 prompts for each line of input.  
   
 The program handles any number of sets of input on a single input file. Each  
 set starts with a regular expression, and continues with any number of data  
 lines to be matched against the pattern. An empty line signals the end of the  
 set. The regular expressions are given enclosed in any non-alphameric  
 delimiters, for example  
   
   /(a|bc)x+yz/  
   
 and may be followed by i, m, s, or x to set the PCRE_CASELESS, PCRE_MULTILINE,  
 PCRE_DOTALL, or PCRE_EXTENDED options, respectively. These options have the  
 same effect as they do in Perl.  
   
 There are also some upper case options that do not match Perl options: /A, /E,  
 and /X set PCRE_ANCHORED, PCRE_DOLLAR_ENDONLY, and PCRE_EXTRA respectively.  
 The /D option is a PCRE debugging feature. It causes the internal form of  
 compiled regular expressions to be output after compilation. The /S option  
 causes pcre_study() to be called after the expression has been compiled, and  
 the results used when the expression is matched. If /I is present as well as  
 /S, then pcre_study() is called with the PCRE_CASELESS option.  
   
 Finally, the /P option causes pcretest to call PCRE via the POSIX wrapper API  
 rather than its native API. When this is done, all other options except /i and  
 /m are ignored. REG_ICASE is set if /i is present, and REG_NEWLINE is set if /m  
 is present. The wrapper functions force PCRE_DOLLAR_ENDONLY always, and  
 PCRE_DOTALL unless REG_NEWLINE is set.  
   
 A regular expression can extend over several lines of input; the newlines are  
 included in it. See the testinput file for many examples.  
   
 Before each data line is passed to pcre_exec(), leading and trailing whitespace  
 is removed, and it is then scanned for \ escapes. The following are recognized:  
   
   \a     alarm (= BEL)  
   \b     backspace  
   \e     escape  
   \f     formfeed  
   \n     newline  
   \r     carriage return  
   \t     tab  
   \v     vertical tab  
   \nnn   octal character (up to 3 octal digits)  
   \xhh   hexadecimal character (up to 2 hex digits)  
   
   \A     pass the PCRE_ANCHORED option to pcre_exec()  
   \B     pass the PCRE_NOTBOL option to pcre_exec()  
   \E     pass the PCRE_DOLLAR_ENDONLY option to pcre_exec()  
   \I     pass the PCRE_CASELESS option to pcre_exec()  
   \M     pass the PCRE_MULTILINE option to pcre_exec()  
   \S     pass the PCRE_DOTALL option to pcre_exec()  
   \Odd   set the size of the output vector passed to pcre_exec() to dd  
            (any number of decimal digits)  
   \Z     pass the PCRE_NOTEOL option to pcre_exec()  
   
 A backslash followed by anything else just escapes the anything else. If the  
 very last character is a backslash, it is ignored. This gives a way of passing  
 an empty line as data, since a real empty line terminates the data input.  
   
 If /P was present on the regex, causing the POSIX wrapper API to be used, only  
 \B, and \Z have any effect, causing REG_NOTBOL and REG_NOTEOL to be passed to  
 regexec() respectively.  
   
 When a match succeeds, pcretest outputs the list of identified substrings that  
 pcre_exec() returns, starting with number 0 for the string that matched the  
 whole pattern. Here is an example of an interactive pcretest run.  
   
   $ pcretest  
   Testing Perl-Compatible Regular Expressions  
   PCRE version 0.90 08-Sep-1997  
   
       re> /^abc(\d+)/  
     data> abc123  
    0: abc123  
    1: 123  
     data> xyz  
   No match  
   
 Note that while patterns can be continued over several lines (a plain ">"  
 prompt is used for continuations), data lines may not. However newlines can be  
 included in data by means of the \n escape.  
   
 If the -p option is given to pcretest, it is equivalent to adding /P to each  
 regular expression: the POSIX wrapper API is used to call PCRE. None of the  
 following flags has any effect in this case.  
   
 If the option -d is given to pcretest, it is equivalent to adding /D to each  
 regular expression: the internal form is output after compilation.  
   
 If the option -i (for "information") is given to pcretest, it calls pcre_info()  
 after compiling an expression, and outputs the information it gets back. If the  
 pattern is studied, the results of that are also output.  
   
 If the option -s is given to pcretest, it outputs the size of each compiled  
 pattern after it has been compiled.  
   
 If the -t option is given, each compile, study, and match is run 2000 times  
 while being timed, and the resulting time per compile or match is output in  
 milliseconds. Do not set -t with -s, because you will then get the size output  
 2000 times and the timing will be distorted.  
   
   
   
 The perltest program  
 --------------------  
   
 The perltest program tests Perl's regular expressions; it has the same  
 specification as pcretest, and so can be given identical input, except that  
 input patterns can be followed only by Perl's lower case options.  
   
 The data lines are processed as Perl strings, so if they contain $ or @  
 characters, these have to be escaped. For this reason, all such characters in  
 the testinput file are escaped so that it can be used for perltest as well as  
 for pcretest, and the special upper case options such as /A that pcretest  
 recognizes are not used in this file. The output should be identical, apart  
 from the initial identifying banner.  
   
 The testinput2 file is not suitable for feeding to Perltest, since it does  
 make use of the special upper case options and escapes that pcretest uses to  
 test additional features of PCRE.  
632    
633  Philip Hazel <ph10@cam.ac.uk>    pcre_chartables.c.dist  a default set of character tables that assume ASCII
634  October 1997                              coding; used, unless --enable-rebuild-chartables is
635                                specified, by copying to pcre_chartables.c
636    
637      pcreposix.c             )
638      pcre_compile.c          )
639      pcre_config.c           )
640      pcre_dfa_exec.c         )
641      pcre_exec.c             )
642      pcre_fullinfo.c         )
643      pcre_get.c              ) sources for the functions in the library,
644      pcre_globals.c          )   and some internal functions that they use
645      pcre_info.c             )
646      pcre_maketables.c       )
647      pcre_newline.c          )
648      pcre_ord2utf8.c         )
649      pcre_refcount.c         )
650      pcre_study.c            )
651      pcre_tables.c           )
652      pcre_try_flipped.c      )
653      pcre_ucd.c              )
654      pcre_valid_utf8.c       )
655      pcre_version.c          )
656      pcre_xclass.c           )
657      pcre_printint.src       ) debugging function that is #included in pcretest,
658                              )   and can also be #included in pcre_compile()
659      pcre.h.in               template for pcre.h when built by "configure"
660      pcreposix.h             header for the external POSIX wrapper API
661      pcre_internal.h         header for internal use
662      ucp.h                   header for Unicode property handling
663    
664      config.h.in             template for config.h, which is built by "configure"
665    
666      pcrecpp.h               public header file for the C++ wrapper
667      pcrecpparg.h.in         template for another C++ header file
668      pcre_scanner.h          public header file for C++ scanner functions
669      pcrecpp.cc              )
670      pcre_scanner.cc         ) source for the C++ wrapper library
671    
672      pcre_stringpiece.h.in   template for pcre_stringpiece.h, the header for the
673                                C++ stringpiece functions
674      pcre_stringpiece.cc     source for the C++ stringpiece functions
675    
676    (B) Source files for programs that use PCRE:
677    
678      pcredemo.c              simple demonstration of coding calls to PCRE
679      pcregrep.c              source of a grep utility that uses PCRE
680      pcretest.c              comprehensive test program
681    
682    (C) Auxiliary files:
683    
684      132html                 script to turn "man" pages into HTML
685      AUTHORS                 information about the author of PCRE
686      ChangeLog               log of changes to the code
687      CleanTxt                script to clean nroff output for txt man pages
688      Detrail                 script to remove trailing spaces
689      HACKING                 some notes about the internals of PCRE
690      INSTALL                 generic installation instructions
691      LICENCE                 conditions for the use of PCRE
692      COPYING                 the same, using GNU's standard name
693      Makefile.in             ) template for Unix Makefile, which is built by
694                              )   "configure"
695      Makefile.am             ) the automake input that was used to create
696                              )   Makefile.in
697      NEWS                    important changes in this release
698      NON-UNIX-USE            notes on building PCRE on non-Unix systems
699      PrepareRelease          script to make preparations for "make dist"
700      README                  this file
701      RunTest                 a Unix shell script for running tests
702      RunGrepTest             a Unix shell script for pcregrep tests
703      aclocal.m4              m4 macros (generated by "aclocal")
704      config.guess            ) files used by libtool,
705      config.sub              )   used only when building a shared library
706      configure               a configuring shell script (built by autoconf)
707      configure.ac            ) the autoconf input that was used to build
708                              )   "configure" and config.h
709      depcomp                 ) script to find program dependencies, generated by
710                              )   automake
711      doc/*.3                 man page sources for the PCRE functions
712      doc/*.1                 man page sources for pcregrep and pcretest
713      doc/index.html.src      the base HTML page
714      doc/html/*              HTML documentation
715      doc/pcre.txt            plain text version of the man pages
716      doc/pcretest.txt        plain text documentation of test program
717      doc/perltest.txt        plain text documentation of Perl test program
718      install-sh              a shell script for installing files
719      libpcre.pc.in           template for libpcre.pc for pkg-config
720      libpcrecpp.pc.in        template for libpcrecpp.pc for pkg-config
721      ltmain.sh               file used to build a libtool script
722      missing                 ) common stub for a few missing GNU programs while
723                              )   installing, generated by automake
724      mkinstalldirs           script for making install directories
725      perltest.pl             Perl test program
726      pcre-config.in          source of script which retains PCRE information
727      pcrecpp_unittest.cc          )
728      pcre_scanner_unittest.cc     ) test programs for the C++ wrapper
729      pcre_stringpiece_unittest.cc )
730      testdata/testinput*     test data for main library tests
731      testdata/testoutput*    expected test results
732      testdata/grep*          input and output for pcregrep tests
733    
734    (D) Auxiliary files for cmake support
735    
736      cmake/COPYING-CMAKE-SCRIPTS
737      cmake/FindPackageHandleStandardArgs.cmake
738      cmake/FindReadline.cmake
739      CMakeLists.txt
740      config-cmake.h.in
741    
742    (E) Auxiliary files for VPASCAL
743    
744      makevp.bat
745      makevp_c.txt
746      makevp_l.txt
747      pcregexp.pas
748    
749    (F) Auxiliary files for building PCRE "by hand"
750    
751      pcre.h.generic          ) a version of the public PCRE header file
752                              )   for use in non-"configure" environments
753      config.h.generic        ) a version of config.h for use in non-"configure"
754                              )   environments
755    
756    (F) Miscellaneous
757    
758      RunTest.bat            a script for running tests under Windows
759    
760    Philip Hazel
761    Email local part: ph10
762    Email domain: cam.ac.uk
763    Last updated: 17 March 2009

Legend:
Removed from v.7  
changed lines
  Added in v.392

webmaster@exim.org
ViewVC Help
Powered by ViewVC 1.1.12