1News about PCRE releases 2------------------------ 3 4Release 5.0 13-Sep-04 5--------------------- 6 7The licence under which PCRE is released has been changed to the more 8conventional "BSD" licence. 9 10In the code, some bugs have been fixed, and there are also some major changes 11in this release (which is why I've increased the number to 5.0). Some changes 12are internal rearrangements, and some provide a number of new facilities. The 13new features are: 14 151. There's an "automatic callout" feature that inserts callouts before every 16 item in the regex, and there's a new callout field that gives the position 17 in the pattern - useful for debugging and tracing. 18 192. The extra_data structure can now be used to pass in a set of character 20 tables at exec time. This is useful if compiled regex are saved and re-used 21 at a later time when the tables may not be at the same address. If the 22 default internal tables are used, the pointer saved with the compiled 23 pattern is now set to NULL, which means that you don't need to do anything 24 special unless you are using custom tables. 25 263. It is possible, with some restrictions on the content of the regex, to 27 request "partial" matching. A special return code is given if all of the 28 subject string matched part of the regex. This could be useful for testing 29 an input field as it is being typed. 30 314. There is now some optional support for Unicode character properties, which 32 means that the patterns items such as \p{Lu} and \X can now be used. Only 33 the general category properties are supported. If PCRE is compiled with this 34 support, an additional 90K data structure is include, which increases the 35 size of the library dramatically. 36 375. There is support for saving compiled patterns and re-using them later. 38 396. There is support for running regular expressions that were compiled on a 40 different host with the opposite endianness. 41 427. The pcretest program has been extended to accommodate the new features. 43 44The main internal rearrangement is that sequences of literal characters are no 45longer handled as strings. Instead, each character is handled on its own. This 46makes some UTF-8 handling easier, and makes the support of partial matching 47possible. Compiled patterns containing long literal strings will be larger as a 48result of this change; I hope that performance will not be much affected. 49 50 51Release 4.5 01-Dec-03 52--------------------- 53 54Again mainly a bug-fix and tidying release, with only a couple of new features: 55 561. It's possible now to compile PCRE so that it does not use recursive 57function calls when matching. Instead it gets memory from the heap. This slows 58things down, but may be necessary on systems with limited stacks. 59 602. UTF-8 string checking has been tightened to reject overlong sequences and to 61check that a starting offset points to the start of a character. Failure of the 62latter returns a new error code: PCRE_ERROR_BADUTF8_OFFSET. 63 643. PCRE can now be compiled for systems that use EBCDIC code. 65 66 67Release 4.4 21-Aug-03 68--------------------- 69 70This is mainly a bug-fix and tidying release. The only new feature is that PCRE 71checks UTF-8 strings for validity by default. There is an option to suppress 72this, just in case anybody wants that teeny extra bit of performance. 73 74 75Releases 4.1 - 4.3 76------------------ 77 78Sorry, I forgot about updating the NEWS file for these releases. Please take a 79look at ChangeLog. 80 81 82Release 4.0 17-Feb-03 83--------------------- 84 85There have been a lot of changes for the 4.0 release, adding additional 86functionality and mending bugs. Below is a list of the highlights of the new 87functionality. For full details of these features, please consult the 88documentation. For a complete list of changes, see the ChangeLog file. 89 901. Support for Perl's \Q...\E escapes. 91 922. "Possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's Java 93package. They provide some syntactic sugar for simple cases of "atomic 94grouping". 95 963. Support for the \G assertion. It is true when the current matching position 97is at the start point of the match. 98 994. A new feature that provides some of the functionality that Perl provides 100with (?{...}). The facility is termed a "callout". The way it is done in PCRE 101is for the caller to provide an optional function, by setting pcre_callout to 102its entry point. To get the function called, the regex must include (?C) at 103appropriate points. 104 1055. Support for recursive calls to individual subpatterns. This makes it really 106easy to get totally confused. 107 1086. Support for named subpatterns. The Python syntax (?P<name>...) is used to 109name a group. 110 1117. Several extensions to UTF-8 support; it is now fairly complete. There is an 112option for pcregrep to make it operate in UTF-8 mode. 113 1148. The single man page has been split into a number of separate man pages. 115These also give rise to individual HTML pages which are put in a separate 116directory. There is an index.html page that lists them all. Some hyperlinking 117between the pages has been installed. 118 119 120Release 3.5 15-Aug-01 121--------------------- 122 1231. The configuring system has been upgraded to use later versions of autoconf 124and libtool. By default it builds both a shared and a static library if the OS 125supports it. You can use --disable-shared or --disable-static on the configure 126command if you want only one of them. 127 1282. The pcretest utility is now installed along with pcregrep because it is 129useful for users (to test regexs) and by doing this, it automatically gets 130relinked by libtool. The documentation has been turned into a man page, so 131there are now .1, .txt, and .html versions in /doc. 132 1333. Upgrades to pcregrep: 134 (i) Added long-form option names like gnu grep. 135 (ii) Added --help to list all options with an explanatory phrase. 136 (iii) Added -r, --recursive to recurse into sub-directories. 137 (iv) Added -f, --file to read patterns from a file. 138 1394. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure 140script, to force use of CR or LF instead of \n in the source. On non-Unix 141systems, the value can be set in config.h. 142 1435. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an 144absolute limit. Changed the text of the error message to make this clear, and 145likewise updated the man page. 146 1476. The limit of 99 on the number of capturing subpatterns has been removed. 148The new limit is 65535, which I hope will not be a "real" limit. 149 150 151Release 3.3 01-Aug-00 152--------------------- 153 154There is some support for UTF-8 character strings. This is incomplete and 155experimental. The documentation describes what is and what is not implemented. 156Otherwise, this is just a bug-fixing release. 157 158 159Release 3.0 01-Feb-00 160--------------------- 161 1621. A "configure" script is now used to configure PCRE for Unix systems. It 163builds a Makefile, a config.h file, and the pcre-config script. 164 1652. PCRE is built as a shared library by default. 166 1673. There is support for POSIX classes such as [:alpha:]. 168 1695. There is an experimental recursion feature. 170 171---------------------------------------------------------------------------- 172 IMPORTANT FOR THOSE UPGRADING FROM VERSIONS BEFORE 2.00 173 174Please note that there has been a change in the API such that a larger 175ovector is required at matching time, to provide some additional workspace. 176The new man page has details. This change was necessary in order to support 177some of the new functionality in Perl 5.005. 178 179 IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.00 180 181Another (I hope this is the last!) change has been made to the API for the 182pcre_compile() function. An additional argument has been added to make it 183possible to pass over a pointer to character tables built in the current 184locale by pcre_maketables(). To use the default tables, this new arguement 185should be passed as NULL. 186 187 IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.05 188 189Yet another (and again I hope this really is the last) change has been made 190to the API for the pcre_exec() function. An additional argument has been 191added to make it possible to start the match other than at the start of the 192subject string. This is important if there are lookbehinds. The new man 193page has the details, but you just want to convert existing programs, all 194you need to do is to stick in a new fifth argument to pcre_exec(), with a 195value of zero. For example, change 196 197 pcre_exec(pattern, extra, subject, length, options, ovec, ovecsize) 198to 199 pcre_exec(pattern, extra, subject, length, 0, options, ovec, ovecsize) 200 201**** 202