xref: /PHP-7.0/ext/pcre/pcrelib/NEWS (revision 5f9df47e)
1News about PCRE releases
2------------------------
3
4Release 8.38 23-November-2015
5-----------------------------
6
7This is bug-fix release. Note that this library (now called PCRE1) is now being
8maintained for bug fixes only. New projects are advised to use the new PCRE2
9libraries.
10
11
12Release 8.37 28-April-2015
13--------------------------
14
15This is bug-fix release. Note that this library (now called PCRE1) is now being
16maintained for bug fixes only. New projects are advised to use the new PCRE2
17libraries.
18
19
20Release 8.36 26-September-2014
21------------------------------
22
23This is primarily a bug-fix release. However, in addition, the Unicode data
24tables have been updated to Unicode 7.0.0.
25
26
27Release 8.35 04-April-2014
28--------------------------
29
30There have been performance improvements for classes containing non-ASCII
31characters and the "auto-possessification" feature has been extended. Other
32minor improvements have been implemented and bugs fixed. There is a new callout
33feature to enable applications to do detailed stack checks at compile time, to
34avoid running out of stack for deeply nested parentheses. The JIT compiler has
35been extended with experimental support for ARM-64, MIPS-64, and PPC-LE.
36
37
38Release 8.34 15-December-2013
39-----------------------------
40
41As well as fixing the inevitable bugs, performance has been improved by
42refactoring and extending the amount of "auto-possessification" that PCRE does.
43Other notable changes:
44
45.  Implemented PCRE_INFO_MATCH_EMPTY, which yields 1 if the pattern can match
46   an empty string. If it can, pcretest shows this in its information output.
47
48.  A back reference to a named subpattern when there is more than one of the
49   same name now checks them in the order in which they appear in the pattern.
50   The first one that is set is used for the reference. Previously only the
51   first one was inspected. This change makes PCRE more compatible with Perl.
52
53.  Unicode character properties were updated from Unicode 6.3.0.
54
55.  The character VT has been added to the set of characters that match \s and
56   are generally treated as white space, following this same change in Perl
57   5.18. There is now no difference between "Perl space" and "POSIX space".
58
59.  Perl has changed its handling of \8 and \9. If there is no previously
60   encountered capturing group of those numbers, they are treated as the
61   literal characters 8 and 9 instead of a binary zero followed by the
62   literals. PCRE now does the same.
63
64.  Following Perl, added \o{} to specify codepoints in octal, making it
65   possible to specify values greater than 0777 and also making them
66   unambiguous.
67
68.  In UCP mode, \s was not matching two of the characters that Perl matches,
69   namely NEL (U+0085) and MONGOLIAN VOWEL SEPARATOR (U+180E), though they
70   were matched by \h.
71
72.  Add JIT support for the 64 bit TileGX architecture.
73
74.  Upgraded the handling of the POSIX classes [:graph:], [:print:], and
75   [:punct:] when PCRE_UCP is set so as to include the same characters as Perl
76   does in Unicode mode.
77
78.  Perl no longer allows group names to start with digits, so I have made this
79   change also in PCRE.
80
81.  Added support for [[:<:]] and [[:>:]] as used in the BSD POSIX library to
82   mean "start of word" and "end of word", respectively, as a transition aid.
83
84
85Release 8.33 28-May-2013
86--------------------------
87
88A number of bugs are fixed, and some performance improvements have been made.
89There are also some new features, of which these are the most important:
90
91.  The behaviour of the backtracking verbs has been rationalized and
92   documented in more detail.
93
94.  JIT now supports callouts and all of the backtracking verbs.
95
96.  Unicode validation has been updated in the light of Unicode Corrigendum #9,
97   which points out that "non characters" are not "characters that may not
98   appear in Unicode strings" but rather "characters that are reserved for
99   internal use and have only local meaning".
100
101.  (*LIMIT_MATCH=d) and (*LIMIT_RECURSION=d) have been added so that the
102   creator of a pattern can specify lower (but not higher) limits for the
103   matching process.
104
105.  The PCRE_NEVER_UTF option is available to prevent pattern-writers from using
106   the (*UTF) feature, as this could be a security issue.
107
108
109Release 8.32 30-November-2012
110-----------------------------
111
112This release fixes a number of bugs, but also has some new features. These are
113the highlights:
114
115.  There is now support for 32-bit character strings and UTF-32. Like the
116   16-bit support, this is done by compiling a separate 32-bit library.
117
118.  \X now matches a Unicode extended grapheme cluster.
119
120.  Case-independent matching of Unicode characters that have more than one
121   "other case" now makes all three (or more) characters equivalent. This
122   applies, for example, to Greek Sigma, which has two lowercase versions.
123
124.  Unicode character properties are updated to Unicode 6.2.0.
125
126.  The EBCDIC support, which had decayed, has had a spring clean.
127
128.  A number of JIT optimizations have been added, which give faster JIT
129   execution speed. In addition, a new direct interface to JIT execution is
130   available. This bypasses some of the sanity checks of pcre_exec() to give a
131   noticeable speed-up.
132
133.  A number of issues in pcregrep have been fixed, making it more compatible
134   with GNU grep. In particular, --exclude and --include (and variants) apply
135   to all files now, not just those obtained from scanning a directory
136   recursively. In Windows environments, the default action for directories is
137   now "skip" instead of "read" (which provokes an error).
138
139.  If the --only-matching (-o) option in pcregrep is specified multiple
140   times, each one causes appropriate output. For example, -o1 -o2 outputs the
141   substrings matched by the 1st and 2nd capturing parentheses. A separating
142   string can be specified by --om-separator (default empty).
143
144.  When PCRE is built via Autotools using a version of gcc that has the
145   "visibility" feature, it is used to hide internal library functions that are
146   not part of the public API.
147
148
149Release 8.31 06-July-2012
150-------------------------
151
152This is mainly a bug-fixing release, with a small number of developments:
153
154. The JIT compiler now supports partial matching and the (*MARK) and
155  (*COMMIT) verbs.
156
157. PCRE_INFO_MAXLOOKBEHIND can be used to find the longest lookbehind in a
158  pattern.
159
160. There should be a performance improvement when using the heap instead of the
161  stack for recursion.
162
163. pcregrep can now be linked with libedit as an alternative to libreadline.
164
165. pcregrep now has a --file-list option where the list of files to scan is
166  given as a file.
167
168. pcregrep now recognizes binary files and there are related options.
169
170. The Unicode tables have been updated to 6.1.0.
171
172As always, the full list of changes is in the ChangeLog file.
173
174
175Release 8.30 04-February-2012
176-----------------------------
177
178Release 8.30 introduces a major new feature: support for 16-bit character
179strings, compiled as a separate library. There are a few changes to the
1808-bit library, in addition to some bug fixes.
181
182. The pcre_info() function, which has been obsolete for over 10 years, has
183  been removed.
184
185. When a compiled pattern was saved to a file and later reloaded on a host
186  with different endianness, PCRE used automatically to swap the bytes in some
187  of the data fields. With the advent of the 16-bit library, where more of this
188  swapping is needed, it is no longer done automatically. Instead, the bad
189  endianness is detected and a specific error is given. The user can then call
190  a new function called pcre_pattern_to_host_byte_order() (or an equivalent
191  16-bit function) to do the swap.
192
193. In UTF-8 mode, the values 0xd800 to 0xdfff are not legal Unicode
194  code points and are now faulted. (They are the so-called "surrogates"
195  that are reserved for coding high values in UTF-16.)
196
197
198Release 8.21 12-Dec-2011
199------------------------
200
201This is almost entirely a bug-fix release. The only new feature is the ability
202to obtain the size of the memory used by the JIT compiler.
203
204
205Release 8.20 21-Oct-2011
206------------------------
207
208The main change in this release is the inclusion of Zoltan Herczeg's
209just-in-time compiler support, which can be accessed by building PCRE with
210--enable-jit. Large performance benefits can be had in many situations. 8.20
211also fixes an unfortunate bug that was introduced in 8.13 as well as tidying up
212a number of infelicities and differences from Perl.
213
214
215Release 8.13 16-Aug-2011
216------------------------
217
218This is mainly a bug-fix release. There has been a lot of internal refactoring.
219The Unicode tables have been updated. The only new feature in the library is
220the passing of *MARK information to callouts. Some additions have been made to
221pcretest to make testing easier and more comprehensive. There is a new option
222for pcregrep to adjust its internal buffer size.
223
224
225Release 8.12 15-Jan-2011
226------------------------
227
228This release fixes some bugs in pcregrep, one of which caused the tests to fail
229on 64-bit big-endian systems. There are no changes to the code of the library.
230
231
232Release 8.11 10-Dec-2010
233------------------------
234
235A number of bugs in the library and in pcregrep have been fixed. As always, see
236ChangeLog for details. The following are the non-bug-fix changes:
237
238. Added --match-limit and --recursion-limit to pcregrep.
239
240. Added an optional parentheses number to the -o and --only-matching options
241  of pcregrep.
242
243. Changed the way PCRE_PARTIAL_HARD affects the matching of $, \z, \Z, \b, and
244  \B.
245
246. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
247  bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
248
249. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
250  START_OPTIMIZE option, which is now allowed at compile time
251
252
253Release 8.10 25-Jun-2010
254------------------------
255
256There are two major additions: support for (*MARK) and friends, and the option
257PCRE_UCP, which changes the behaviour of \b, \d, \s, and \w (and their
258opposites) so that they make use of Unicode properties. There are also a number
259of lesser new features, and several bugs have been fixed. A new option,
260--line-buffered, has been added to pcregrep, for use when it is connected to
261pipes.
262
263
264Release 8.02 19-Mar-2010
265------------------------
266
267Another bug-fix release.
268
269
270Release 8.01 19-Jan-2010
271------------------------
272
273This is a bug-fix release. Several bugs in the code itself and some bugs and
274infelicities in the build system have been fixed.
275
276
277Release 8.00 19-Oct-09
278----------------------
279
280Bugs have been fixed in the library and in pcregrep. There are also some
281enhancements. Restrictions on patterns used for partial matching have been
282removed, extra information is given for partial matches, the partial matching
283process has been improved, and an option to make a partial match override a
284full match is available. The "study" process has been enhanced by finding a
285lower bound matching length. Groups with duplicate numbers may now have
286duplicated names without the use of PCRE_DUPNAMES. However, they may not have
287different names. The documentation has been revised to reflect these changes.
288The version number has been expanded to 3 digits as it is clear that the rate
289of change is not slowing down.
290
291
292Release 7.9 11-Apr-09
293---------------------
294
295Mostly bugfixes and tidies with just a couple of minor functional additions.
296
297
298Release 7.8 05-Sep-08
299---------------------
300
301More bug fixes, plus a performance improvement in Unicode character property
302lookup.
303
304
305Release 7.7 07-May-08
306---------------------
307
308This is once again mainly a bug-fix release, but there are a couple of new
309features.
310
311
312Release 7.6 28-Jan-08
313---------------------
314
315The main reason for having this release so soon after 7.5 is because it fixes a
316potential buffer overflow problem in pcre_compile() when run in UTF-8 mode. In
317addition, the CMake configuration files have been brought up to date.
318
319
320Release 7.5 10-Jan-08
321---------------------
322
323This is mainly a bug-fix release. However the ability to link pcregrep with
324libz or libbz2 and the ability to link pcretest with libreadline have been
325added. Also the --line-offsets and --file-offsets options were added to
326pcregrep.
327
328
329Release 7.4 21-Sep-07
330---------------------
331
332The only change of specification is the addition of options to control whether
333\R matches any Unicode line ending (the default) or just CR, LF, and CRLF.
334Otherwise, the changes are bug fixes and a refactoring to reduce the number of
335relocations needed in a shared library. There have also been some documentation
336updates, in particular, some more information about using CMake to build PCRE
337has been added to the NON-UNIX-USE file.
338
339
340Release 7.3 28-Aug-07
341---------------------
342
343Most changes are bug fixes. Some that are not:
344
3451. There is some support for Perl 5.10's experimental "backtracking control
346   verbs" such as (*PRUNE).
347
3482. UTF-8 checking is now as per RFC 3629 instead of RFC 2279; this is more
349   restrictive in the strings it accepts.
350
3513. Checking for potential integer overflow has been made more dynamic, and as a
352   consequence there is no longer a hard limit on the size of a subpattern that
353   has a limited repeat count.
354
3554. When CRLF is a valid line-ending sequence, pcre_exec() and pcre_dfa_exec()
356   no longer advance by two characters instead of one when an unanchored match
357   fails at CRLF if there are explicit CR or LF matches within the pattern.
358   This gets rid of some anomalous effects that previously occurred.
359
3605. Some PCRE-specific settings for varying the newline options at the start of
361   a pattern have been added.
362
363
364Release 7.2 19-Jun-07
365---------------------
366
367WARNING: saved patterns that were compiled by earlier versions of PCRE must be
368recompiled for use with 7.2 (necessitated by the addition of \K, \h, \H, \v,
369and \V).
370
371Correction to the notes for 7.1: the note about shared libraries for Windows is
372wrong. Previously, three libraries were built, but each could function
373independently. For example, the pcreposix library also included all the
374functions from the basic pcre library. The change is that the three libraries
375are no longer independent. They are like the Unix libraries. To use the
376pcreposix functions, for example, you need to link with both the pcreposix and
377the basic pcre library.
378
379Some more features from Perl 5.10 have been added:
380
381  (?-n) and (?+n) relative references for recursion and subroutines.
382
383  (?(-n) and (?(+n) relative references as conditions.
384
385  \k{name} and \g{name} are synonyms for \k<name>.
386
387  \K to reset the start of the matched string; for example, (foo)\Kbar
388  matches bar preceded by foo, but only sets bar as the matched string.
389
390  (?| introduces a group where the capturing parentheses in each alternative
391  start from the same number; for example, (?|(abc)|(xyz)) sets capturing
392  parentheses number 1 in both cases.
393
394  \h, \H, \v, \V match horizontal and vertical whitespace, respectively.
395
396
397Release 7.1 24-Apr-07
398---------------------
399
400There is only one new feature in this release: a linebreak setting of
401PCRE_NEWLINE_ANYCRLF. It is a cut-down version of PCRE_NEWLINE_ANY, which
402recognizes only CRLF, CR, and LF as linebreaks.
403
404A few bugs are fixed (see ChangeLog for details), but the major change is a
405complete re-implementation of the build system. This now has full Autotools
406support and so is now "standard" in some sense. It should help with compiling
407PCRE in a wide variety of environments.
408
409NOTE: when building shared libraries for Windows, three dlls are now built,
410called libpcre, libpcreposix, and libpcrecpp. Previously, everything was
411included in a single dll.
412
413Another important change is that the dftables auxiliary program is no longer
414compiled and run at "make" time by default. Instead, a default set of character
415tables (assuming ASCII coding) is used. If you want to use dftables to generate
416the character tables as previously, add --enable-rebuild-chartables to the
417"configure" command. You must do this if you are compiling PCRE to run on a
418system that uses EBCDIC code.
419
420There is a discussion about character tables in the README file. The default is
421not to use dftables so that that there is no problem when cross-compiling.
422
423
424Release 7.0 19-Dec-06
425---------------------
426
427This release has a new major number because there have been some internal
428upheavals to facilitate the addition of new optimizations and other facilities,
429and to make subsequent maintenance and extension easier. Compilation is likely
430to be a bit slower, but there should be no major effect on runtime performance.
431Previously compiled patterns are NOT upwards compatible with this release. If
432you have saved compiled patterns from a previous release, you will have to
433re-compile them. Important changes that are visible to users are:
434
4351. The Unicode property tables have been updated to Unicode 5.0.0, which adds
436   some more scripts.
437
4382. The option PCRE_NEWLINE_ANY causes PCRE to recognize any Unicode newline
439   sequence as a newline.
440
4413. The \R escape matches a single Unicode newline sequence as a single unit.
442
4434. New features that will appear in Perl 5.10 are now in PCRE. These include
444   alternative Perl syntax for named parentheses, and Perl syntax for
445   recursion.
446
4475. The C++ wrapper interface has been extended by the addition of a
448   QuoteMeta function and the ability to allow copy construction and
449   assignment.
450
451For a complete list of changes, see the ChangeLog file.
452
453
454Release 6.7 04-Jul-06
455---------------------
456
457The main additions to this release are the ability to use the same name for
458multiple sets of parentheses, and support for CRLF line endings in both the
459library and pcregrep (and in pcretest for testing).
460
461Thanks to Ian Taylor, the stack usage for many kinds of pattern has been
462significantly reduced for certain subject strings.
463
464
465Release 6.5 01-Feb-06
466---------------------
467
468Important changes in this release:
469
4701. A number of new features have been added to pcregrep.
471
4722. The Unicode property tables have been updated to Unicode 4.1.0, and the
473   supported properties have been extended with script names such as "Arabic",
474   and the derived properties "Any" and "L&". This has necessitated a change to
475   the interal format of compiled patterns. Any saved compiled patterns that
476   use \p or \P must be recompiled.
477
4783. The specification of recursion in patterns has been changed so that all
479   recursive subpatterns are automatically treated as atomic groups. Thus, for
480   example, (?R) is treated as if it were (?>(?R)). This is necessary because
481   otherwise there are situations where recursion does not work.
482
483See the ChangeLog for a complete list of changes, which include a number of bug
484fixes and tidies.
485
486
487Release 6.0 07-Jun-05
488---------------------
489
490The release number has been increased to 6.0 because of the addition of several
491major new pieces of functionality.
492
493A new function, pcre_dfa_exec(), which implements pattern matching using a DFA
494algorithm, has been added. This has a number of advantages for certain cases,
495though it does run more slowly, and lacks the ability to capture substrings. On
496the other hand, it does find all matches, not just the first, and it works
497better for partial matching. The pcrematching man page discusses the
498differences.
499
500The pcretest program has been enhanced so that it can make use of the new
501pcre_dfa_exec() matching function and the extra features it provides.
502
503The distribution now includes a C++ wrapper library. This is built
504automatically if a C++ compiler is found. The pcrecpp man page discusses this
505interface.
506
507The code itself has been re-organized into many more files, one for each
508function, so it no longer requires everything to be linked in when static
509linkage is used. As a consequence, some internal functions have had to have
510their names exposed. These functions all have names starting with _pcre_. They
511are undocumented, and are not intended for use by outside callers.
512
513The pcregrep program has been enhanced with new functionality such as
514multiline-matching and options for output more matching context. See the
515ChangeLog for a complete list of changes to the library and the utility
516programs.
517
518
519Release 5.0 13-Sep-04
520---------------------
521
522The licence under which PCRE is released has been changed to the more
523conventional "BSD" licence.
524
525In the code, some bugs have been fixed, and there are also some major changes
526in this release (which is why I've increased the number to 5.0). Some changes
527are internal rearrangements, and some provide a number of new facilities. The
528new features are:
529
5301. There's an "automatic callout" feature that inserts callouts before every
531   item in the regex, and there's a new callout field that gives the position
532   in the pattern - useful for debugging and tracing.
533
5342. The extra_data structure can now be used to pass in a set of character
535   tables at exec time. This is useful if compiled regex are saved and re-used
536   at a later time when the tables may not be at the same address. If the
537   default internal tables are used, the pointer saved with the compiled
538   pattern is now set to NULL, which means that you don't need to do anything
539   special unless you are using custom tables.
540
5413. It is possible, with some restrictions on the content of the regex, to
542   request "partial" matching. A special return code is given if all of the
543   subject string matched part of the regex. This could be useful for testing
544   an input field as it is being typed.
545
5464. There is now some optional support for Unicode character properties, which
547   means that the patterns items such as \p{Lu} and \X can now be used. Only
548   the general category properties are supported. If PCRE is compiled with this
549   support, an additional 90K data structure is include, which increases the
550   size of the library dramatically.
551
5525. There is support for saving compiled patterns and re-using them later.
553
5546. There is support for running regular expressions that were compiled on a
555   different host with the opposite endianness.
556
5577. The pcretest program has been extended to accommodate the new features.
558
559The main internal rearrangement is that sequences of literal characters are no
560longer handled as strings. Instead, each character is handled on its own. This
561makes some UTF-8 handling easier, and makes the support of partial matching
562possible. Compiled patterns containing long literal strings will be larger as a
563result of this change; I hope that performance will not be much affected.
564
565
566Release 4.5 01-Dec-03
567---------------------
568
569Again mainly a bug-fix and tidying release, with only a couple of new features:
570
5711. It's possible now to compile PCRE so that it does not use recursive
572function calls when matching. Instead it gets memory from the heap. This slows
573things down, but may be necessary on systems with limited stacks.
574
5752. UTF-8 string checking has been tightened to reject overlong sequences and to
576check that a starting offset points to the start of a character. Failure of the
577latter returns a new error code: PCRE_ERROR_BADUTF8_OFFSET.
578
5793. PCRE can now be compiled for systems that use EBCDIC code.
580
581
582Release 4.4 21-Aug-03
583---------------------
584
585This is mainly a bug-fix and tidying release. The only new feature is that PCRE
586checks UTF-8 strings for validity by default. There is an option to suppress
587this, just in case anybody wants that teeny extra bit of performance.
588
589
590Releases 4.1 - 4.3
591------------------
592
593Sorry, I forgot about updating the NEWS file for these releases. Please take a
594look at ChangeLog.
595
596
597Release 4.0 17-Feb-03
598---------------------
599
600There have been a lot of changes for the 4.0 release, adding additional
601functionality and mending bugs. Below is a list of the highlights of the new
602functionality. For full details of these features, please consult the
603documentation. For a complete list of changes, see the ChangeLog file.
604
6051. Support for Perl's \Q...\E escapes.
606
6072. "Possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's Java
608package. They provide some syntactic sugar for simple cases of "atomic
609grouping".
610
6113. Support for the \G assertion. It is true when the current matching position
612is at the start point of the match.
613
6144. A new feature that provides some of the functionality that Perl provides
615with (?{...}). The facility is termed a "callout". The way it is done in PCRE
616is for the caller to provide an optional function, by setting pcre_callout to
617its entry point. To get the function called, the regex must include (?C) at
618appropriate points.
619
6205. Support for recursive calls to individual subpatterns. This makes it really
621easy to get totally confused.
622
6236. Support for named subpatterns. The Python syntax (?P<name>...) is used to
624name a group.
625
6267. Several extensions to UTF-8 support; it is now fairly complete. There is an
627option for pcregrep to make it operate in UTF-8 mode.
628
6298. The single man page has been split into a number of separate man pages.
630These also give rise to individual HTML pages which are put in a separate
631directory. There is an index.html page that lists them all. Some hyperlinking
632between the pages has been installed.
633
634
635Release 3.5 15-Aug-01
636---------------------
637
6381. The configuring system has been upgraded to use later versions of autoconf
639and libtool. By default it builds both a shared and a static library if the OS
640supports it. You can use --disable-shared or --disable-static on the configure
641command if you want only one of them.
642
6432. The pcretest utility is now installed along with pcregrep because it is
644useful for users (to test regexs) and by doing this, it automatically gets
645relinked by libtool. The documentation has been turned into a man page, so
646there are now .1, .txt, and .html versions in /doc.
647
6483. Upgrades to pcregrep:
649   (i)   Added long-form option names like gnu grep.
650   (ii)  Added --help to list all options with an explanatory phrase.
651   (iii) Added -r, --recursive to recurse into sub-directories.
652   (iv)  Added -f, --file to read patterns from a file.
653
6544. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
655script, to force use of CR or LF instead of \n in the source. On non-Unix
656systems, the value can be set in config.h.
657
6585. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
659absolute limit. Changed the text of the error message to make this clear, and
660likewise updated the man page.
661
6626. The limit of 99 on the number of capturing subpatterns has been removed.
663The new limit is 65535, which I hope will not be a "real" limit.
664
665
666Release 3.3 01-Aug-00
667---------------------
668
669There is some support for UTF-8 character strings. This is incomplete and
670experimental. The documentation describes what is and what is not implemented.
671Otherwise, this is just a bug-fixing release.
672
673
674Release 3.0 01-Feb-00
675---------------------
676
6771. A "configure" script is now used to configure PCRE for Unix systems. It
678builds a Makefile, a config.h file, and the pcre-config script.
679
6802. PCRE is built as a shared library by default.
681
6823. There is support for POSIX classes such as [:alpha:].
683
6845. There is an experimental recursion feature.
685
686----------------------------------------------------------------------------
687          IMPORTANT FOR THOSE UPGRADING FROM VERSIONS BEFORE 2.00
688
689Please note that there has been a change in the API such that a larger
690ovector is required at matching time, to provide some additional workspace.
691The new man page has details. This change was necessary in order to support
692some of the new functionality in Perl 5.005.
693
694          IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.00
695
696Another (I hope this is the last!) change has been made to the API for the
697pcre_compile() function. An additional argument has been added to make it
698possible to pass over a pointer to character tables built in the current
699locale by pcre_maketables(). To use the default tables, this new argument
700should be passed as NULL.
701
702          IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.05
703
704Yet another (and again I hope this really is the last) change has been made
705to the API for the pcre_exec() function. An additional argument has been
706added to make it possible to start the match other than at the start of the
707subject string. This is important if there are lookbehinds. The new man
708page has the details, but you just want to convert existing programs, all
709you need to do is to stick in a new fifth argument to pcre_exec(), with a
710value of zero. For example, change
711
712  pcre_exec(pattern, extra, subject, length, options, ovec, ovecsize)
713to
714  pcre_exec(pattern, extra, subject, length, 0, options, ovec, ovecsize)
715
716****
717