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diff --git a/gtk+-mingw/share/man/man3/pcreunicode.3 b/gtk+-mingw/share/man/man3/pcreunicode.3 deleted file mode 100644 index e8dc80e..0000000 --- a/gtk+-mingw/share/man/man3/pcreunicode.3 +++ /dev/null @@ -1,225 +0,0 @@ -.TH PCREUNICODE 3 "14 April 2012" "PCRE 8.30" -.SH NAME -PCRE - Perl-compatible regular expressions -.SH "UTF-8, UTF-16, AND UNICODE PROPERTY SUPPORT" -.rs -.sp -From Release 8.30, in addition to its previous UTF-8 support, PCRE also -supports UTF-16 by means of a separate 16-bit library. This can be built as -well as, or instead of, the 8-bit library. -. -. -.SH "UTF-8 SUPPORT" -.rs -.sp -In order process UTF-8 strings, you must build PCRE's 8-bit library with UTF -support, and, in addition, you must call -.\" HREF -\fBpcre_compile()\fP -.\" -with the PCRE_UTF8 option flag, or the pattern must start with the sequence -(*UTF8). When either of these is the case, both the pattern and any subject -strings that are matched against it are treated as UTF-8 strings instead of -strings of 1-byte characters. -. -. -.SH "UTF-16 SUPPORT" -.rs -.sp -In order process UTF-16 strings, you must build PCRE's 16-bit library with UTF -support, and, in addition, you must call -.\" HTML <a href="pcre_compile.html"> -.\" </a> -\fBpcre16_compile()\fP -.\" -with the PCRE_UTF16 option flag, or the pattern must start with the sequence -(*UTF16). When either of these is the case, both the pattern and any subject -strings that are matched against it are treated as UTF-16 strings instead of -strings of 16-bit characters. -. -. -.SH "UTF SUPPORT OVERHEAD" -.rs -.sp -If you compile PCRE with UTF support, but do not use it at run time, the -library will be a bit bigger, but the additional run time overhead is limited -to testing the PCRE_UTF8/16 flag occasionally, so should not be very big. -. -. -.SH "UNICODE PROPERTY SUPPORT" -.rs -.sp -If PCRE is built with Unicode character property support (which implies UTF -support), the escape sequences \ep{..}, \eP{..}, and \eX can be used. -The available properties that can be tested are limited to the general -category properties such as Lu for an upper case letter or Nd for a decimal -number, the Unicode script names such as Arabic or Han, and the derived -properties Any and L&. A full list is given in the -.\" HREF -\fBpcrepattern\fP -.\" -documentation. Only the short names for properties are supported. For example, -\ep{L} matches a letter. Its Perl synonym, \ep{Letter}, is not supported. -Furthermore, in Perl, many properties may optionally be prefixed by "Is", for -compatibility with Perl 5.6. PCRE does not support this. -. -. -.\" HTML <a name="utf8strings"></a> -.SS "Validity of UTF-8 strings" -.rs -.sp -When you set the PCRE_UTF8 flag, the byte strings passed as patterns and -subjects are (by default) checked for validity on entry to the relevant -functions. The entire string is checked before any other processing takes -place. From release 7.3 of PCRE, the check is according the rules of RFC 3629, -which are themselves derived from the Unicode specification. Earlier releases -of PCRE followed the rules of RFC 2279, which allows the full range of 31-bit -values (0 to 0x7FFFFFFF). The current check allows only values in the range U+0 -to U+10FFFF, excluding U+D800 to U+DFFF. -.P -The excluded code points are the "Surrogate Area" of Unicode. They are reserved -for use by UTF-16, where they are used in pairs to encode codepoints with -values greater than 0xFFFF. The code points that are encoded by UTF-16 pairs -are available independently in the UTF-8 encoding. (In other words, the whole -surrogate thing is a fudge for UTF-16 which unfortunately messes up UTF-8.) -.P -If an invalid UTF-8 string is passed to PCRE, an error return is given. At -compile time, the only additional information is the offset to the first byte -of the failing character. The run-time functions \fBpcre_exec()\fP and -\fBpcre_dfa_exec()\fP also pass back this information, as well as a more -detailed reason code if the caller has provided memory in which to do this. -.P -In some situations, you may already know that your strings are valid, and -therefore want to skip these checks in order to improve performance, for -example in the case of a long subject string that is being scanned repeatedly -with different patterns. If you set the PCRE_NO_UTF8_CHECK flag at compile time -or at run time, PCRE assumes that the pattern or subject it is given -(respectively) contains only valid UTF-8 codes. In this case, it does not -diagnose an invalid UTF-8 string. -.P -If you pass an invalid UTF-8 string when PCRE_NO_UTF8_CHECK is set, what -happens depends on why the string is invalid. If the string conforms to the -"old" definition of UTF-8 (RFC 2279), it is processed as a string of characters -in the range 0 to 0x7FFFFFFF by \fBpcre_dfa_exec()\fP and the interpreted -version of \fBpcre_exec()\fP. In other words, apart from the initial validity -test, these functions (when in UTF-8 mode) handle strings according to the more -liberal rules of RFC 2279. However, the just-in-time (JIT) optimization for -\fBpcre_exec()\fP supports only RFC 3629. If you are using JIT optimization, or -if the string does not even conform to RFC 2279, the result is undefined. Your -program may crash. -.P -If you want to process strings of values in the full range 0 to 0x7FFFFFFF, -encoded in a UTF-8-like manner as per the old RFC, you can set -PCRE_NO_UTF8_CHECK to bypass the more restrictive test. However, in this -situation, you will have to apply your own validity check, and avoid the use of -JIT optimization. -. -. -.\" HTML <a name="utf16strings"></a> -.SS "Validity of UTF-16 strings" -.rs -.sp -When you set the PCRE_UTF16 flag, the strings of 16-bit data units that are -passed as patterns and subjects are (by default) checked for validity on entry -to the relevant functions. Values other than those in the surrogate range -U+D800 to U+DFFF are independent code points. Values in the surrogate range -must be used in pairs in the correct manner. -.P -If an invalid UTF-16 string is passed to PCRE, an error return is given. At -compile time, the only additional information is the offset to the first data -unit of the failing character. The run-time functions \fBpcre16_exec()\fP and -\fBpcre16_dfa_exec()\fP also pass back this information, as well as a more -detailed reason code if the caller has provided memory in which to do this. -.P -In some situations, you may already know that your strings are valid, and -therefore want to skip these checks in order to improve performance. If you set -the PCRE_NO_UTF16_CHECK flag at compile time or at run time, PCRE assumes that -the pattern or subject it is given (respectively) contains only valid UTF-16 -sequences. In this case, it does not diagnose an invalid UTF-16 string. -. -. -.SS "General comments about UTF modes" -.rs -.sp -1. Codepoints less than 256 can be specified by either braced or unbraced -hexadecimal escape sequences (for example, \ex{b3} or \exb3). Larger values -have to use braced sequences. -.P -2. Octal numbers up to \e777 are recognized, and in UTF-8 mode, they match -two-byte characters for values greater than \e177. -.P -3. Repeat quantifiers apply to complete UTF characters, not to individual -data units, for example: \ex{100}{3}. -.P -4. The dot metacharacter matches one UTF character instead of a single data -unit. -.P -5. The escape sequence \eC can be used to match a single byte in UTF-8 mode, or -a single 16-bit data unit in UTF-16 mode, but its use can lead to some strange -effects because it breaks up multi-unit characters (see the description of \eC -in the -.\" HREF -\fBpcrepattern\fP -.\" -documentation). The use of \eC is not supported in the alternative matching -function \fBpcre[16]_dfa_exec()\fP, nor is it supported in UTF mode by the JIT -optimization of \fBpcre[16]_exec()\fP. If JIT optimization is requested for a -UTF pattern that contains \eC, it will not succeed, and so the matching will -be carried out by the normal interpretive function. -.P -6. The character escapes \eb, \eB, \ed, \eD, \es, \eS, \ew, and \eW correctly -test characters of any code value, but, by default, the characters that PCRE -recognizes as digits, spaces, or word characters remain the same set as in -non-UTF mode, all with values less than 256. This remains true even when PCRE -is built to include Unicode property support, because to do otherwise would -slow down PCRE in many common cases. Note in particular that this applies to -\eb and \eB, because they are defined in terms of \ew and \eW. If you really -want to test for a wider sense of, say, "digit", you can use explicit Unicode -property tests such as \ep{Nd}. Alternatively, if you set the PCRE_UCP option, -the way that the character escapes work is changed so that Unicode properties -are used to determine which characters match. There are more details in the -section on -.\" HTML <a href="pcrepattern.html#genericchartypes"> -.\" </a> -generic character types -.\" -in the -.\" HREF -\fBpcrepattern\fP -.\" -documentation. -.P -7. Similarly, characters that match the POSIX named character classes are all -low-valued characters, unless the PCRE_UCP option is set. -.P -8. However, the horizontal and vertical white space matching escapes (\eh, \eH, -\ev, and \eV) do match all the appropriate Unicode characters, whether or not -PCRE_UCP is set. -.P -9. Case-insensitive matching applies only to characters whose values are less -than 128, unless PCRE is built with Unicode property support. Even when Unicode -property support is available, PCRE still uses its own character tables when -checking the case of low-valued characters, so as not to degrade performance. -The Unicode property information is used only for characters with higher -values. Furthermore, PCRE supports case-insensitive matching only when there is -a one-to-one mapping between a letter's cases. There are a small number of -many-to-one mappings in Unicode; these are not supported by PCRE. -. -. -.SH AUTHOR -.rs -.sp -.nf -Philip Hazel -University Computing Service -Cambridge CB2 3QH, England. -.fi -. -. -.SH REVISION -.rs -.sp -.nf -Last updated: 14 April 2012 -Copyright (c) 1997-2012 University of Cambridge. -.fi |