ViewVC logotype

Contents of /code/trunk/README

Parent Directory Parent Directory | Revision Log Revision Log

Revision 49 - (show annotations)
Sat Feb 24 21:39:33 2007 UTC (8 years, 7 months ago) by nigel
File size: 12527 byte(s)
Error occurred while calculating annotation data.
Load pcre-3.3 into code/trunk.
1 README file for PCRE (Perl-compatible regular expression library)
2 -----------------------------------------------------------------
4 The latest release of PCRE is always available from
6 ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.gz
8 Please read the NEWS file if you are upgrading from a previous release.
10 PCRE has its own native API, but a set of "wrapper" functions that are based on
11 the POSIX API are also supplied in the library libpcreposix. Note that this
12 just provides a POSIX calling interface to PCRE: the regular expressions
13 themselves still follow Perl syntax and semantics. The header file
14 for the POSIX-style functions is called pcreposix.h. The official POSIX name is
15 regex.h, but I didn't want to risk possible problems with existing files of
16 that name by distributing it that way. To use it with an existing program that
17 uses the POSIX API, it will have to be renamed or pointed at by a link.
20 Building PCRE on a Unix system
21 ------------------------------
23 To build PCRE on a Unix system, run the "configure" command in the PCRE
24 distribution directory. This is a standard GNU "autoconf" configuration script,
25 for which generic instructions are supplied in INSTALL. On many systems just
26 running "./configure" is sufficient, but the usual methods of changing standard
27 defaults are available. For example,
29 CFLAGS='-O2 -Wall' ./configure --prefix=/opt/local
31 specifies that the C compiler should be run with the flags '-O2 -Wall' instead
32 of the default, and that "make install" should install PCRE under /opt/local
33 instead of the default /usr/local.
35 If you want to make use of the experimential, incomplete support for UTF-8
36 character strings in PCRE, you must add --enable-utf8 to the "configure"
37 command. Without it, the code for handling UTF-8 is not included in the
38 library. (Even when included, it still has to be enabled by an option at run
39 time.)
41 The "configure" script builds four files:
43 . Makefile is built by copying Makefile.in and making substitutions.
44 . config.h is built by copying config.in and making substitutions.
45 . pcre-config is built by copying pcre-config.in and making substitutions.
46 . RunTest is a script for running tests
48 Once "configure" has run, you can run "make". It builds two libraries called
49 libpcre and libpcreposix, a test program called pcretest, and the pcregrep
50 command. You can use "make install" to copy these, and the public header file
51 pcre.h, to appropriate live directories on your system, in the normal way.
53 Running "make install" also installs the command pcre-config, which can be used
54 to recall information about the PCRE configuration and installation. For
55 example,
57 pcre-config --version
59 prints the version number, and
61 pcre-config --libs
63 outputs information about where the library is installed. This command can be
64 included in makefiles for programs that use PCRE, saving the programmer from
65 having to remember too many details.
68 Shared libraries on Unix systems
69 --------------------------------
71 The default distribution builds PCRE as two shared libraries. This support is
72 new and experimental and may not work on all systems. It relies on the
73 "libtool" scripts - these are distributed with PCRE. It should build a
74 "libtool" script and use this to compile and link shared libraries, which are
75 placed in a subdirectory called .libs. The programs pcretest and pcregrep are
76 built to use these uninstalled libraries by means of wrapper scripts. When you
77 use "make install" to install shared libraries, pcregrep and pcretest are
78 automatically re-built to use the newly installed libraries. However, only
79 pcregrep is installed, as pcretest is really just a test program.
81 To build PCRE using static libraries you must use --disable-shared when
82 configuring it. For example
84 ./configure --prefix=/usr/gnu --disable-shared
86 Then run "make" in the usual way.
89 Building on non-Unix systems
90 ----------------------------
92 For a non-Unix system, read the comments in the file NON-UNIX-USE. PCRE has
93 been compiled on Windows systems and on Macintoshes, but I don't know the
94 details because I don't use those systems. It should be straightforward to
95 build PCRE on any system that has a Standard C compiler, because it uses only
96 Standard C functions.
99 Testing PCRE
100 ------------
102 To test PCRE on a Unix system, run the RunTest script in the pcre directory.
103 (This can also be run by "make runtest", "make check", or "make test".) For
104 other systems, see the instruction in NON-UNIX-USE.
106 The script runs the pcretest test program (which is documented in
107 doc/pcretest.txt) on each of the testinput files (in the testdata directory) in
108 turn, and compares the output with the contents of the corresponding testoutput
109 file. A file called testtry is used to hold the output from pcretest. To run
110 pcretest on just one of the test files, give its number as an argument to
111 RunTest, for example:
113 RunTest 3
115 The first and third test files can also be fed directly into the perltest
116 script to check that Perl gives the same results. The third file requires the
117 additional features of release 5.005, which is why it is kept separate from the
118 main test input, which needs only Perl 5.004. In the long run, when 5.005 (or
119 higher) is widespread, these two test files may get amalgamated.
121 The second set of tests check pcre_fullinfo(), pcre_info(), pcre_study(),
122 pcre_copy_substring(), pcre_get_substring(), pcre_get_substring_list(), error
123 detection, and run-time flags that are specific to PCRE, as well as the POSIX
124 wrapper API. It also uses the debugging flag to check some of the internals of
125 pcre_compile().
127 If you build PCRE with a locale setting that is not the standard C locale, the
128 character tables may be different (see next paragraph). In some cases, this may
129 cause failures in the second set of tests. For example, in a locale where the
130 isprint() function yields TRUE for characters in the range 128-255, the use of
131 [:isascii:] inside a character class defines a different set of characters, and
132 this shows up in this test as a difference in the compiled code, which is being
133 listed for checking. Where the comparison test output contains [\x00-\x7f] the
134 test will contain [\x00-\xff], and similarly in some other cases. This is not a
135 bug in PCRE.
137 The fourth set of tests checks pcre_maketables(), the facility for building a
138 set of character tables for a specific locale and using them instead of the
139 default tables. The tests make use of the "fr" (French) locale. Before running
140 the test, the script checks for the presence of this locale by running the
141 "locale" command. If that command fails, or if it doesn't include "fr" in the
142 list of available locales, the fourth test cannot be run, and a comment is
143 output to say why. If running this test produces instances of the error
145 ** Failed to set locale "fr"
147 in the comparison output, it means that locale is not available on your system,
148 despite being listed by "locale". This does not mean that PCRE is broken.
150 The fifth test checks the experimental, incomplete UTF-8 support. It is not run
151 automatically unless PCRE is built with UTF-8 support. This file can be fed
152 directly to the perltest8 script, which requires Perl 5.6 or higher. The sixth
153 file tests internal UTF-8 features of PCRE that are not relevant to Perl.
156 Character tables
157 ----------------
159 PCRE uses four tables for manipulating and identifying characters. The final
160 argument of the pcre_compile() function is a pointer to a block of memory
161 containing the concatenated tables. A call to pcre_maketables() can be used to
162 generate a set of tables in the current locale. If the final argument for
163 pcre_compile() is passed as NULL, a set of default tables that is built into
164 the binary is used.
166 The source file called chartables.c contains the default set of tables. This is
167 not supplied in the distribution, but is built by the program dftables
168 (compiled from dftables.c), which uses the ANSI C character handling functions
169 such as isalnum(), isalpha(), isupper(), islower(), etc. to build the table
170 sources. This means that the default C locale which is set for your system will
171 control the contents of these default tables. You can change the default tables
172 by editing chartables.c and then re-building PCRE. If you do this, you should
173 probably also edit Makefile to ensure that the file doesn't ever get
174 re-generated.
176 The first two 256-byte tables provide lower casing and case flipping functions,
177 respectively. The next table consists of three 32-byte bit maps which identify
178 digits, "word" characters, and white space, respectively. These are used when
179 building 32-byte bit maps that represent character classes.
181 The final 256-byte table has bits indicating various character types, as
182 follows:
184 1 white space character
185 2 letter
186 4 decimal digit
187 8 hexadecimal digit
188 16 alphanumeric or '_'
189 128 regular expression metacharacter or binary zero
191 You should not alter the set of characters that contain the 128 bit, as that
192 will cause PCRE to malfunction.
195 Manifest
196 --------
198 The distribution should contain the following files:
200 (A) The actual source files of the PCRE library functions and their
201 headers:
203 dftables.c auxiliary program for building chartables.c
204 get.c )
205 maketables.c )
206 study.c ) source of
207 pcre.c ) the functions
208 pcreposix.c )
209 pcre.in "source" for the header for the external API; pcre.h
210 is built from this by "configure"
211 pcreposix.h header for the external POSIX wrapper API
212 internal.h header for internal use
213 config.in template for config.h, which is built by configure
215 (B) Auxiliary files:
217 AUTHORS information about the author of PCRE
218 ChangeLog log of changes to the code
219 INSTALL generic installation instructions
220 LICENCE conditions for the use of PCRE
221 COPYING the same, using GNU's standard name
222 Makefile.in template for Unix Makefile, which is built by configure
223 NEWS important changes in this release
224 NON-UNIX-USE notes on building PCRE on non-Unix systems
225 README this file
226 RunTest.in template for a Unix shell script for running tests
227 config.guess ) files used by libtool,
228 config.sub ) used only when building a shared library
229 configure a configuring shell script (built by autoconf)
230 configure.in the autoconf input used to build configure
231 doc/Tech.Notes notes on the encoding
232 doc/pcre.3 man page source for the PCRE functions
233 doc/pcre.html HTML version
234 doc/pcre.txt plain text version
235 doc/pcreposix.3 man page source for the POSIX wrapper API
236 doc/pcreposix.html HTML version
237 doc/pcreposix.txt plain text version
238 doc/pcretest.txt documentation of test program
239 doc/perltest.txt documentation of Perl test program
240 doc/pcregrep.1 man page source for the pcregrep utility
241 doc/pcregrep.html HTML version
242 doc/pcregrep.txt plain text version
243 install-sh a shell script for installing files
244 ltconfig ) files used to build "libtool",
245 ltmain.sh ) used only when building a shared library
246 pcretest.c test program
247 perltest Perl test program
248 perltest8 Perl test program for UTF-8 tests
249 pcregrep.c source of a grep utility that uses PCRE
250 pcre-config.in source of script which retains PCRE information
251 testdata/testinput1 test data, compatible with Perl 5.004 and 5.005
252 testdata/testinput2 test data for error messages and non-Perl things
253 testdata/testinput3 test data, compatible with Perl 5.005
254 testdata/testinput4 test data for locale-specific tests
255 testdata/testinput5 test data for UTF-8 tests compatible with Perl 5.6
256 testdata/testinput6 test data for other UTF-8 tests
257 testdata/testoutput1 test results corresponding to testinput1
258 testdata/testoutput2 test results corresponding to testinput2
259 testdata/testoutput3 test results corresponding to testinput3
260 testdata/testoutput4 test results corresponding to testinput4
261 testdata/testoutput5 test results corresponding to testinput5
262 testdata/testoutput6 test results corresponding to testinput6
264 (C) Auxiliary files for Win32 DLL
266 dll.mk
267 pcre.def
269 Philip Hazel <ph10@cam.ac.uk>
270 August 2000

  ViewVC Help
Powered by ViewVC 1.1.5