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Revision 411 - (show annotations)
Fri Apr 10 15:40:21 2009 UTC (12 years, 6 months ago) by ph10
File size: 17342 byte(s)
Wrap fileno/isatty defs for Windows in #ifndefs
1 News about PCRE releases
2 ------------------------
4 Release 7.9 01-Apr-09
5 ---------------------
7 Mostly bugfixes and tidies with just a couple of minor functional additions.
10 Release 7.8 05-Sep-08
11 ---------------------
13 More bug fixes, plus a performance improvement in Unicode character property
14 lookup.
17 Release 7.7 07-May-08
18 ---------------------
20 This is once again mainly a bug-fix release, but there are a couple of new
21 features.
24 Release 7.6 28-Jan-08
25 ---------------------
27 The main reason for having this release so soon after 7.5 is because it fixes a
28 potential buffer overflow problem in pcre_compile() when run in UTF-8 mode. In
29 addition, the CMake configuration files have been brought up to date.
32 Release 7.5 10-Jan-08
33 ---------------------
35 This is mainly a bug-fix release. However the ability to link pcregrep with
36 libz or libbz2 and the ability to link pcretest with libreadline have been
37 added. Also the --line-offsets and --file-offsets options were added to
38 pcregrep.
41 Release 7.4 21-Sep-07
42 ---------------------
44 The only change of specification is the addition of options to control whether
45 \R matches any Unicode line ending (the default) or just CR, LF, and CRLF.
46 Otherwise, the changes are bug fixes and a refactoring to reduce the number of
47 relocations needed in a shared library. There have also been some documentation
48 updates, in particular, some more information about using CMake to build PCRE
49 has been added to the NON-UNIX-USE file.
52 Release 7.3 28-Aug-07
53 ---------------------
55 Most changes are bug fixes. Some that are not:
57 1. There is some support for Perl 5.10's experimental "backtracking control
58 verbs" such as (*PRUNE).
60 2. UTF-8 checking is now as per RFC 3629 instead of RFC 2279; this is more
61 restrictive in the strings it accepts.
63 3. Checking for potential integer overflow has been made more dynamic, and as a
64 consequence there is no longer a hard limit on the size of a subpattern that
65 has a limited repeat count.
67 4. When CRLF is a valid line-ending sequence, pcre_exec() and pcre_dfa_exec()
68 no longer advance by two characters instead of one when an unanchored match
69 fails at CRLF if there are explicit CR or LF matches within the pattern.
70 This gets rid of some anomalous effects that previously occurred.
72 5. Some PCRE-specific settings for varying the newline options at the start of
73 a pattern have been added.
76 Release 7.2 19-Jun-07
77 ---------------------
79 WARNING: saved patterns that were compiled by earlier versions of PCRE must be
80 recompiled for use with 7.2 (necessitated by the addition of \K, \h, \H, \v,
81 and \V).
83 Correction to the notes for 7.1: the note about shared libraries for Windows is
84 wrong. Previously, three libraries were built, but each could function
85 independently. For example, the pcreposix library also included all the
86 functions from the basic pcre library. The change is that the three libraries
87 are no longer independent. They are like the Unix libraries. To use the
88 pcreposix functions, for example, you need to link with both the pcreposix and
89 the basic pcre library.
91 Some more features from Perl 5.10 have been added:
93 (?-n) and (?+n) relative references for recursion and subroutines.
95 (?(-n) and (?(+n) relative references as conditions.
97 \k{name} and \g{name} are synonyms for \k<name>.
99 \K to reset the start of the matched string; for example, (foo)\Kbar
100 matches bar preceded by foo, but only sets bar as the matched string.
102 (?| introduces a group where the capturing parentheses in each alternative
103 start from the same number; for example, (?|(abc)|(xyz)) sets capturing
104 parentheses number 1 in both cases.
106 \h, \H, \v, \V match horizontal and vertical whitespace, respectively.
109 Release 7.1 24-Apr-07
110 ---------------------
112 There is only one new feature in this release: a linebreak setting of
113 PCRE_NEWLINE_ANYCRLF. It is a cut-down version of PCRE_NEWLINE_ANY, which
114 recognizes only CRLF, CR, and LF as linebreaks.
116 A few bugs are fixed (see ChangeLog for details), but the major change is a
117 complete re-implementation of the build system. This now has full Autotools
118 support and so is now "standard" in some sense. It should help with compiling
119 PCRE in a wide variety of environments.
121 NOTE: when building shared libraries for Windows, three dlls are now built,
122 called libpcre, libpcreposix, and libpcrecpp. Previously, everything was
123 included in a single dll.
125 Another important change is that the dftables auxiliary program is no longer
126 compiled and run at "make" time by default. Instead, a default set of character
127 tables (assuming ASCII coding) is used. If you want to use dftables to generate
128 the character tables as previously, add --enable-rebuild-chartables to the
129 "configure" command. You must do this if you are compiling PCRE to run on a
130 system that uses EBCDIC code.
132 There is a discussion about character tables in the README file. The default is
133 not to use dftables so that that there is no problem when cross-compiling.
136 Release 7.0 19-Dec-06
137 ---------------------
139 This release has a new major number because there have been some internal
140 upheavals to facilitate the addition of new optimizations and other facilities,
141 and to make subsequent maintenance and extension easier. Compilation is likely
142 to be a bit slower, but there should be no major effect on runtime performance.
143 Previously compiled patterns are NOT upwards compatible with this release. If
144 you have saved compiled patterns from a previous release, you will have to
145 re-compile them. Important changes that are visible to users are:
147 1. The Unicode property tables have been updated to Unicode 5.0.0, which adds
148 some more scripts.
150 2. The option PCRE_NEWLINE_ANY causes PCRE to recognize any Unicode newline
151 sequence as a newline.
153 3. The \R escape matches a single Unicode newline sequence as a single unit.
155 4. New features that will appear in Perl 5.10 are now in PCRE. These include
156 alternative Perl syntax for named parentheses, and Perl syntax for
157 recursion.
159 5. The C++ wrapper interface has been extended by the addition of a
160 QuoteMeta function and the ability to allow copy construction and
161 assignment.
163 For a complete list of changes, see the ChangeLog file.
166 Release 6.7 04-Jul-06
167 ---------------------
169 The main additions to this release are the ability to use the same name for
170 multiple sets of parentheses, and support for CRLF line endings in both the
171 library and pcregrep (and in pcretest for testing).
173 Thanks to Ian Taylor, the stack usage for many kinds of pattern has been
174 significantly reduced for certain subject strings.
177 Release 6.5 01-Feb-06
178 ---------------------
180 Important changes in this release:
182 1. A number of new features have been added to pcregrep.
184 2. The Unicode property tables have been updated to Unicode 4.1.0, and the
185 supported properties have been extended with script names such as "Arabic",
186 and the derived properties "Any" and "L&". This has necessitated a change to
187 the interal format of compiled patterns. Any saved compiled patterns that
188 use \p or \P must be recompiled.
190 3. The specification of recursion in patterns has been changed so that all
191 recursive subpatterns are automatically treated as atomic groups. Thus, for
192 example, (?R) is treated as if it were (?>(?R)). This is necessary because
193 otherwise there are situations where recursion does not work.
195 See the ChangeLog for a complete list of changes, which include a number of bug
196 fixes and tidies.
199 Release 6.0 07-Jun-05
200 ---------------------
202 The release number has been increased to 6.0 because of the addition of several
203 major new pieces of functionality.
205 A new function, pcre_dfa_exec(), which implements pattern matching using a DFA
206 algorithm, has been added. This has a number of advantages for certain cases,
207 though it does run more slowly, and lacks the ability to capture substrings. On
208 the other hand, it does find all matches, not just the first, and it works
209 better for partial matching. The pcrematching man page discusses the
210 differences.
212 The pcretest program has been enhanced so that it can make use of the new
213 pcre_dfa_exec() matching function and the extra features it provides.
215 The distribution now includes a C++ wrapper library. This is built
216 automatically if a C++ compiler is found. The pcrecpp man page discusses this
217 interface.
219 The code itself has been re-organized into many more files, one for each
220 function, so it no longer requires everything to be linked in when static
221 linkage is used. As a consequence, some internal functions have had to have
222 their names exposed. These functions all have names starting with _pcre_. They
223 are undocumented, and are not intended for use by outside callers.
225 The pcregrep program has been enhanced with new functionality such as
226 multiline-matching and options for output more matching context. See the
227 ChangeLog for a complete list of changes to the library and the utility
228 programs.
231 Release 5.0 13-Sep-04
232 ---------------------
234 The licence under which PCRE is released has been changed to the more
235 conventional "BSD" licence.
237 In the code, some bugs have been fixed, and there are also some major changes
238 in this release (which is why I've increased the number to 5.0). Some changes
239 are internal rearrangements, and some provide a number of new facilities. The
240 new features are:
242 1. There's an "automatic callout" feature that inserts callouts before every
243 item in the regex, and there's a new callout field that gives the position
244 in the pattern - useful for debugging and tracing.
246 2. The extra_data structure can now be used to pass in a set of character
247 tables at exec time. This is useful if compiled regex are saved and re-used
248 at a later time when the tables may not be at the same address. If the
249 default internal tables are used, the pointer saved with the compiled
250 pattern is now set to NULL, which means that you don't need to do anything
251 special unless you are using custom tables.
253 3. It is possible, with some restrictions on the content of the regex, to
254 request "partial" matching. A special return code is given if all of the
255 subject string matched part of the regex. This could be useful for testing
256 an input field as it is being typed.
258 4. There is now some optional support for Unicode character properties, which
259 means that the patterns items such as \p{Lu} and \X can now be used. Only
260 the general category properties are supported. If PCRE is compiled with this
261 support, an additional 90K data structure is include, which increases the
262 size of the library dramatically.
264 5. There is support for saving compiled patterns and re-using them later.
266 6. There is support for running regular expressions that were compiled on a
267 different host with the opposite endianness.
269 7. The pcretest program has been extended to accommodate the new features.
271 The main internal rearrangement is that sequences of literal characters are no
272 longer handled as strings. Instead, each character is handled on its own. This
273 makes some UTF-8 handling easier, and makes the support of partial matching
274 possible. Compiled patterns containing long literal strings will be larger as a
275 result of this change; I hope that performance will not be much affected.
278 Release 4.5 01-Dec-03
279 ---------------------
281 Again mainly a bug-fix and tidying release, with only a couple of new features:
283 1. It's possible now to compile PCRE so that it does not use recursive
284 function calls when matching. Instead it gets memory from the heap. This slows
285 things down, but may be necessary on systems with limited stacks.
287 2. UTF-8 string checking has been tightened to reject overlong sequences and to
288 check that a starting offset points to the start of a character. Failure of the
289 latter returns a new error code: PCRE_ERROR_BADUTF8_OFFSET.
291 3. PCRE can now be compiled for systems that use EBCDIC code.
294 Release 4.4 21-Aug-03
295 ---------------------
297 This is mainly a bug-fix and tidying release. The only new feature is that PCRE
298 checks UTF-8 strings for validity by default. There is an option to suppress
299 this, just in case anybody wants that teeny extra bit of performance.
302 Releases 4.1 - 4.3
303 ------------------
305 Sorry, I forgot about updating the NEWS file for these releases. Please take a
306 look at ChangeLog.
309 Release 4.0 17-Feb-03
310 ---------------------
312 There have been a lot of changes for the 4.0 release, adding additional
313 functionality and mending bugs. Below is a list of the highlights of the new
314 functionality. For full details of these features, please consult the
315 documentation. For a complete list of changes, see the ChangeLog file.
317 1. Support for Perl's \Q...\E escapes.
319 2. "Possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's Java
320 package. They provide some syntactic sugar for simple cases of "atomic
321 grouping".
323 3. Support for the \G assertion. It is true when the current matching position
324 is at the start point of the match.
326 4. A new feature that provides some of the functionality that Perl provides
327 with (?{...}). The facility is termed a "callout". The way it is done in PCRE
328 is for the caller to provide an optional function, by setting pcre_callout to
329 its entry point. To get the function called, the regex must include (?C) at
330 appropriate points.
332 5. Support for recursive calls to individual subpatterns. This makes it really
333 easy to get totally confused.
335 6. Support for named subpatterns. The Python syntax (?P<name>...) is used to
336 name a group.
338 7. Several extensions to UTF-8 support; it is now fairly complete. There is an
339 option for pcregrep to make it operate in UTF-8 mode.
341 8. The single man page has been split into a number of separate man pages.
342 These also give rise to individual HTML pages which are put in a separate
343 directory. There is an index.html page that lists them all. Some hyperlinking
344 between the pages has been installed.
347 Release 3.5 15-Aug-01
348 ---------------------
350 1. The configuring system has been upgraded to use later versions of autoconf
351 and libtool. By default it builds both a shared and a static library if the OS
352 supports it. You can use --disable-shared or --disable-static on the configure
353 command if you want only one of them.
355 2. The pcretest utility is now installed along with pcregrep because it is
356 useful for users (to test regexs) and by doing this, it automatically gets
357 relinked by libtool. The documentation has been turned into a man page, so
358 there are now .1, .txt, and .html versions in /doc.
360 3. Upgrades to pcregrep:
361 (i) Added long-form option names like gnu grep.
362 (ii) Added --help to list all options with an explanatory phrase.
363 (iii) Added -r, --recursive to recurse into sub-directories.
364 (iv) Added -f, --file to read patterns from a file.
366 4. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
367 script, to force use of CR or LF instead of \n in the source. On non-Unix
368 systems, the value can be set in config.h.
370 5. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
371 absolute limit. Changed the text of the error message to make this clear, and
372 likewise updated the man page.
374 6. The limit of 99 on the number of capturing subpatterns has been removed.
375 The new limit is 65535, which I hope will not be a "real" limit.
378 Release 3.3 01-Aug-00
379 ---------------------
381 There is some support for UTF-8 character strings. This is incomplete and
382 experimental. The documentation describes what is and what is not implemented.
383 Otherwise, this is just a bug-fixing release.
386 Release 3.0 01-Feb-00
387 ---------------------
389 1. A "configure" script is now used to configure PCRE for Unix systems. It
390 builds a Makefile, a config.h file, and the pcre-config script.
392 2. PCRE is built as a shared library by default.
394 3. There is support for POSIX classes such as [:alpha:].
396 5. There is an experimental recursion feature.
398 ----------------------------------------------------------------------------
401 Please note that there has been a change in the API such that a larger
402 ovector is required at matching time, to provide some additional workspace.
403 The new man page has details. This change was necessary in order to support
404 some of the new functionality in Perl 5.005.
408 Another (I hope this is the last!) change has been made to the API for the
409 pcre_compile() function. An additional argument has been added to make it
410 possible to pass over a pointer to character tables built in the current
411 locale by pcre_maketables(). To use the default tables, this new arguement
412 should be passed as NULL.
416 Yet another (and again I hope this really is the last) change has been made
417 to the API for the pcre_exec() function. An additional argument has been
418 added to make it possible to start the match other than at the start of the
419 subject string. This is important if there are lookbehinds. The new man
420 page has the details, but you just want to convert existing programs, all
421 you need to do is to stick in a new fifth argument to pcre_exec(), with a
422 value of zero. For example, change
424 pcre_exec(pattern, extra, subject, length, options, ovec, ovecsize)
425 to
426 pcre_exec(pattern, extra, subject, length, 0, options, ovec, ovecsize)
428 ****


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