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diff --git a/external-libs/pcre/doc/pcre.3 b/external-libs/pcre/doc/pcre.3 deleted file mode 100644 index c0c71419..00000000 --- a/external-libs/pcre/doc/pcre.3 +++ /dev/null @@ -1,174 +0,0 @@ -.TH PCRE 3 -.SH NAME -PCRE - Perl-compatible regular expressions -.SH DESCRIPTION -.rs -.sp -The PCRE library is a set of functions that implement regular expression -pattern matching using the same syntax and semantics as Perl, with just a few -differences. The current implementation of PCRE (release 4.x) corresponds -approximately with Perl 5.8, including support for UTF-8 encoded strings. -However, this support has to be explicitly enabled; it is not the default. - -PCRE is written in C and released as a C library. However, a number of people -have written wrappers and interfaces of various kinds. A C++ class is included -in these contributions, which can be found in the \fIContrib\fR directory at -the primary FTP site, which is: - -.\" HTML <a href="ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre"> -.\" </a> -ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre - -Details of exactly which Perl regular expression features are and are not -supported by PCRE are given in separate documents. See the -.\" HREF -\fBpcrepattern\fR -.\" -and -.\" HREF -\fBpcrecompat\fR -.\" -pages. - -Some features of PCRE can be included, excluded, or changed when the library is -built. The -.\" HREF -\fBpcre_config()\fR -.\" -function makes it possible for a client to discover which features are -available. Documentation about building PCRE for various operating systems can -be found in the \fBREADME\fR file in the source distribution. - -.SH USER DOCUMENTATION -.rs -.sp -The user documentation for PCRE has been split up into a number of different -sections. In the "man" format, each of these is a separate "man page". In the -HTML format, each is a separate page, linked from the index page. In the plain -text format, all the sections are concatenated, for ease of searching. The -sections are as follows: - - pcre this document - pcreapi details of PCRE's native API - pcrebuild options for building PCRE - pcrecallout details of the callout feature - pcrecompat discussion of Perl compatibility - pcregrep description of the \fBpcregrep\fR command - pcrepattern syntax and semantics of supported - regular expressions - pcreperform discussion of performance issues - pcreposix the POSIX-compatible API - pcresample discussion of the sample program - pcretest the \fBpcretest\fR testing command - -In addition, in the "man" and HTML formats, there is a short page for each -library function, listing its arguments and results. - -.SH LIMITATIONS -.rs -.sp -There are some size limitations in PCRE but it is hoped that they will never in -practice be relevant. - -The maximum length of a compiled pattern is 65539 (sic) bytes if PCRE is -compiled with the default internal linkage size of 2. If you want to process -regular expressions that are truly enormous, you can compile PCRE with an -internal linkage size of 3 or 4 (see the \fBREADME\fR file in the source -distribution and the -.\" HREF -\fBpcrebuild\fR -.\" -documentation for details). If these cases the limit is substantially larger. -However, the speed of execution will be slower. - -All values in repeating quantifiers must be less than 65536. -The maximum number of capturing subpatterns is 65535. - -There is no limit to the number of non-capturing subpatterns, but the maximum -depth of nesting of all kinds of parenthesized subpattern, including capturing -subpatterns, assertions, and other types of subpattern, is 200. - -The maximum length of a subject string is the largest positive number that an -integer variable can hold. However, PCRE uses recursion to handle subpatterns -and indefinite repetition. This means that the available stack space may limit -the size of a subject string that can be processed by certain patterns. - -.\" HTML <a name="utf8support"></a> -.SH UTF-8 SUPPORT -.rs -.sp -Starting at release 3.3, PCRE has had some support for character strings -encoded in the UTF-8 format. For release 4.0 this has been greatly extended to -cover most common requirements. - -In order process UTF-8 strings, you must build PCRE to include UTF-8 support in -the code, and, in addition, you must call -.\" HREF -\fBpcre_compile()\fR -.\" -with the PCRE_UTF8 option flag. When you do this, both the pattern and any -subject strings that are matched against it are treated as UTF-8 strings -instead of just strings of bytes. - -If you compile PCRE with UTF-8 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 flag in several places, so should not be very large. - -The following comments apply when PCRE is running in UTF-8 mode: - -1. When you set the PCRE_UTF8 flag, the strings passed as patterns and subjects -are checked for validity on entry to the relevant functions. If an invalid -UTF-8 string is passed, an error return is given. 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_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. If you pass an invalid UTF-8 string to -PCRE when PCRE_NO_UTF8_CHECK is set, the results are undefined. Your program -may crash. - -2. In a pattern, the escape sequence \\x{...}, where the contents of the braces -is a string of hexadecimal digits, is interpreted as a UTF-8 character whose -code number is the given hexadecimal number, for example: \\x{1234}. If a -non-hexadecimal digit appears between the braces, the item is not recognized. -This escape sequence can be used either as a literal, or within a character -class. - -3. The original hexadecimal escape sequence, \\xhh, matches a two-byte UTF-8 -character if the value is greater than 127. - -4. Repeat quantifiers apply to complete UTF-8 characters, not to individual -bytes, for example: \\x{100}{3}. - -5. The dot metacharacter matches one UTF-8 character instead of a single byte. - -6. The escape sequence \\C can be used to match a single byte in UTF-8 mode, -but its use can lead to some strange effects. - -7. The character escapes \\b, \\B, \\d, \\D, \\s, \\S, \\w, and \\W correctly -test characters of any code value, but the characters that PCRE recognizes as -digits, spaces, or word characters remain the same set as before, all with -values less than 256. - -8. Case-insensitive matching applies only to characters whose values are less -than 256. PCRE does not support the notion of "case" for higher-valued -characters. - -9. PCRE does not support the use of Unicode tables and properties or the Perl -escapes \\p, \\P, and \\X. - -.SH AUTHOR -.rs -.sp -Philip Hazel <ph10@cam.ac.uk> -.br -University Computing Service, -.br -Cambridge CB2 3QG, England. -.br -Phone: +44 1223 334714 - -.in 0 -Last updated: 20 August 2003 -.br -Copyright (c) 1997-2003 University of Cambridge. |