/[pcre]/code/trunk/doc/pcrebuild.3
ViewVC logotype

Diff of /code/trunk/doc/pcrebuild.3

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 93 by nigel, Sat Feb 24 21:41:42 2007 UTC revision 392 by ph10, Tue Mar 17 21:30:30 2009 UTC
# Line 5  PCRE - Perl-compatible regular expressio Line 5  PCRE - Perl-compatible regular expressio
5  .rs  .rs
6  .sp  .sp
7  This document describes the optional features of PCRE that can be selected when  This document describes the optional features of PCRE that can be selected when
8  the library is compiled. They are all selected, or deselected, by providing  the library is compiled. It assumes use of the \fBconfigure\fP script, where
9  options to the \fBconfigure\fP script that is run before the \fBmake\fP  the optional features are selected or deselected by providing options to
10  command. The complete list of options for \fBconfigure\fP (which includes the  \fBconfigure\fP before running the \fBmake\fP command. However, the same
11  standard ones such as the selection of the installation directory) can be  options can be selected in both Unix-like and non-Unix-like environments using
12  obtained by running  the GUI facility of \fBCMakeSetup\fP if you are using \fBCMake\fP instead of
13    \fBconfigure\fP to build PCRE.
14    .P
15    The complete list of options for \fBconfigure\fP (which includes the standard
16    ones such as the selection of the installation directory) can be obtained by
17    running
18  .sp  .sp
19    ./configure --help    ./configure --help
20  .sp  .sp
21  The following sections describe certain options whose names begin with --enable  The following sections include descriptions of options whose names begin with
22  or --disable. These settings specify changes to the defaults for the  --enable or --disable. These settings specify changes to the defaults for the
23  \fBconfigure\fP command. Because of the way that \fBconfigure\fP works,  \fBconfigure\fP command. Because of the way that \fBconfigure\fP works,
24  --enable and --disable always come in pairs, so the complementary option always  --enable and --disable always come in pairs, so the complementary option always
25  exists as well, but as it specifies the default, it is not described.  exists as well, but as it specifies the default, it is not described.
# Line 33  to the \fBconfigure\fP command. Line 38  to the \fBconfigure\fP command.
38  .SH "UTF-8 SUPPORT"  .SH "UTF-8 SUPPORT"
39  .rs  .rs
40  .sp  .sp
41  To build PCRE with support for UTF-8 character strings, add  To build PCRE with support for UTF-8 Unicode character strings, add
42  .sp  .sp
43    --enable-utf8    --enable-utf8
44  .sp  .sp
# Line 41  to the \fBconfigure\fP command. Of itsel Line 46  to the \fBconfigure\fP command. Of itsel
46  strings as UTF-8. As well as compiling PCRE with this option, you also have  strings as UTF-8. As well as compiling PCRE with this option, you also have
47  have to set the PCRE_UTF8 option when you call the \fBpcre_compile()\fP  have to set the PCRE_UTF8 option when you call the \fBpcre_compile()\fP
48  function.  function.
49    .P
50    If you set --enable-utf8 when compiling in an EBCDIC environment, PCRE expects
51    its input to be either ASCII or UTF-8 (depending on the runtime option). It is
52    not possible to support both EBCDIC and UTF-8 codes in the same version of the
53    library. Consequently, --enable-utf8 and --enable-ebcdic are mutually
54    exclusive.
55  .  .
56  .SH "UNICODE CHARACTER PROPERTY SUPPORT"  .SH "UNICODE CHARACTER PROPERTY SUPPORT"
57  .rs  .rs
# Line 56  character properties, you must add Line 67  character properties, you must add
67  to the \fBconfigure\fP command. This implies UTF-8 support, even if you have  to the \fBconfigure\fP command. This implies UTF-8 support, even if you have
68  not explicitly requested it.  not explicitly requested it.
69  .P  .P
70  Including Unicode property support adds around 90K of tables to the PCRE  Including Unicode property support adds around 30K of tables to the PCRE
71  library, approximately doubling its size. Only the general category properties  library. Only the general category properties such as \fILu\fP and \fINd\fP are
72  such as \fILu\fP and \fINd\fP are supported. Details are given in the  supported. Details are given in the
73  .\" HREF  .\" HREF
74  \fBpcrepattern\fP  \fBpcrepattern\fP
75  .\"  .\"
# Line 67  documentation. Line 78  documentation.
78  .SH "CODE VALUE OF NEWLINE"  .SH "CODE VALUE OF NEWLINE"
79  .rs  .rs
80  .sp  .sp
81  By default, PCRE interprets character 10 (linefeed, LF) as indicating the end  By default, PCRE interprets the linefeed (LF) character as indicating the end
82  of a line. This is the normal newline character on Unix-like systems. You can  of a line. This is the normal newline character on Unix-like systems. You can
83  compile PCRE to use character 13 (carriage return, CR) instead, by adding  compile PCRE to use carriage return (CR) instead, by adding
84  .sp  .sp
85    --enable-newline-is-cr    --enable-newline-is-cr
86  .sp  .sp
# Line 83  character sequence CRLF. If you want thi Line 94  character sequence CRLF. If you want thi
94  .sp  .sp
95  to the \fBconfigure\fP command. There is a fourth option, specified by  to the \fBconfigure\fP command. There is a fourth option, specified by
96  .sp  .sp
97      --enable-newline-is-anycrlf
98    .sp
99    which causes PCRE to recognize any of the three sequences CR, LF, or CRLF as
100    indicating a line ending. Finally, a fifth option, specified by
101    .sp
102    --enable-newline-is-any    --enable-newline-is-any
103  .sp  .sp
104  which causes PCRE to recognize any Unicode newline sequence.  causes PCRE to recognize any Unicode newline sequence.
105  .P  .P
106  Whatever line ending convention is selected when PCRE is built can be  Whatever line ending convention is selected when PCRE is built can be
107  overridden when the library functions are called. At build time it is  overridden when the library functions are called. At build time it is
108  conventional to use the standard for your operating system.  conventional to use the standard for your operating system.
109  .  .
110    .SH "WHAT \eR MATCHES"
111    .rs
112    .sp
113    By default, the sequence \eR in a pattern matches any Unicode newline sequence,
114    whatever has been selected as the line ending sequence. If you specify
115    .sp
116      --enable-bsr-anycrlf
117    .sp
118    the default is changed so that \eR matches only CR, LF, or CRLF. Whatever is
119    selected when PCRE is built can be overridden when the library functions are
120    called.
121    .
122  .SH "BUILDING SHARED AND STATIC LIBRARIES"  .SH "BUILDING SHARED AND STATIC LIBRARIES"
123  .rs  .rs
124  .sp  .sp
# Line 137  or four-byte offsets by adding a setting Line 165  or four-byte offsets by adding a setting
165  to the \fBconfigure\fP command. The value given must be 2, 3, or 4. Using  to the \fBconfigure\fP command. The value given must be 2, 3, or 4. Using
166  longer offsets slows down the operation of PCRE because it has to load  longer offsets slows down the operation of PCRE because it has to load
167  additional bytes when handling them.  additional bytes when handling them.
 .P  
 If you build PCRE with an increased link size, test 2 (and test 5 if you are  
 using UTF-8) will fail. Part of the output of these tests is a representation  
 of the compiled pattern, and this changes with the link size.  
168  .  .
169  .SH "AVOIDING EXCESSIVE STACK USAGE"  .SH "AVOIDING EXCESSIVE STACK USAGE"
170  .rs  .rs
# Line 163  build a version of PCRE that works this Line 187  build a version of PCRE that works this
187  .sp  .sp
188  to the \fBconfigure\fP command. With this configuration, PCRE will use the  to the \fBconfigure\fP command. With this configuration, PCRE will use the
189  \fBpcre_stack_malloc\fP and \fBpcre_stack_free\fP variables to call memory  \fBpcre_stack_malloc\fP and \fBpcre_stack_free\fP variables to call memory
190  management functions. Separate functions are provided because the usage is very  management functions. By default these point to \fBmalloc()\fP and
191  predictable: the block sizes requested are always the same, and the blocks are  \fBfree()\fP, but you can replace the pointers so that your own functions are
192  always freed in reverse order. A calling program might be able to implement  used.
193  optimized functions that perform better than the standard \fBmalloc()\fP and  .P
194  \fBfree()\fP functions. PCRE runs noticeably more slowly when built in this  Separate functions are provided rather than using \fBpcre_malloc\fP and
195  way. This option affects only the \fBpcre_exec()\fP function; it is not  \fBpcre_free\fP because the usage is very predictable: the block sizes
196  relevant for the the \fBpcre_dfa_exec()\fP function.  requested are always the same, and the blocks are always freed in reverse
197    order. A calling program might be able to implement optimized functions that
198    perform better than \fBmalloc()\fP and \fBfree()\fP. PCRE runs noticeably more
199    slowly when built in this way. This option affects only the \fBpcre_exec()\fP
200    function; it is not relevant for the the \fBpcre_dfa_exec()\fP function.
201  .  .
202  .SH "LIMITING PCRE RESOURCE USAGE"  .SH "LIMITING PCRE RESOURCE USAGE"
203  .rs  .rs
# Line 202  constraints. However, you can set a lowe Line 230  constraints. However, you can set a lowe
230  .sp  .sp
231  to the \fBconfigure\fP command. This value can also be overridden at run time.  to the \fBconfigure\fP command. This value can also be overridden at run time.
232  .  .
233    .SH "CREATING CHARACTER TABLES AT BUILD TIME"
234    .rs
235    .sp
236    PCRE uses fixed tables for processing characters whose code values are less
237    than 256. By default, PCRE is built with a set of tables that are distributed
238    in the file \fIpcre_chartables.c.dist\fP. These tables are for ASCII codes
239    only. If you add
240    .sp
241      --enable-rebuild-chartables
242    .sp
243    to the \fBconfigure\fP command, the distributed tables are no longer used.
244    Instead, a program called \fBdftables\fP is compiled and run. This outputs the
245    source for new set of tables, created in the default locale of your C runtime
246    system. (This method of replacing the tables does not work if you are cross
247    compiling, because \fBdftables\fP is run on the local host. If you need to
248    create alternative tables when cross compiling, you will have to do so "by
249    hand".)
250    .
251  .SH "USING EBCDIC CODE"  .SH "USING EBCDIC CODE"
252  .rs  .rs
253  .sp  .sp
254  PCRE assumes by default that it will run in an environment where the character  PCRE assumes by default that it will run in an environment where the character
255  code is ASCII (or Unicode, which is a superset of ASCII). PCRE can, however, be  code is ASCII (or Unicode, which is a superset of ASCII). This is the case for
256  compiled to run in an EBCDIC environment by adding  most computer operating systems. PCRE can, however, be compiled to run in an
257    EBCDIC environment by adding
258  .sp  .sp
259    --enable-ebcdic    --enable-ebcdic
260  .sp  .sp
261  to the \fBconfigure\fP command.  to the \fBconfigure\fP command. This setting implies
262    --enable-rebuild-chartables. You should only use it if you know that you are in
263    an EBCDIC environment (for example, an IBM mainframe operating system). The
264    --enable-ebcdic option is incompatible with --enable-utf8.
265    .
266    .SH "PCREGREP OPTIONS FOR COMPRESSED FILE SUPPORT"
267    .rs
268    .sp
269    By default, \fBpcregrep\fP reads all files as plain text. You can build it so
270    that it recognizes files whose names end in \fB.gz\fP or \fB.bz2\fP, and reads
271    them with \fBlibz\fP or \fBlibbz2\fP, respectively, by adding one or both of
272    .sp
273      --enable-pcregrep-libz
274      --enable-pcregrep-libbz2
275    .sp
276    to the \fBconfigure\fP command. These options naturally require that the
277    relevant libraries are installed on your system. Configuration will fail if
278    they are not.
279    .
280    .SH "PCRETEST OPTION FOR LIBREADLINE SUPPORT"
281    .rs
282    .sp
283    If you add
284    .sp
285      --enable-pcretest-libreadline
286    .sp
287    to the \fBconfigure\fP command, \fBpcretest\fP is linked with the
288    \fBlibreadline\fP library, and when its input is from a terminal, it reads it
289    using the \fBreadline()\fP function. This provides line-editing and history
290    facilities. Note that \fBlibreadline\fP is GPL-licenced, so if you distribute a
291    binary of \fBpcretest\fP linked in this way, there may be licensing issues.
292    .P
293    Setting this option causes the \fB-lreadline\fP option to be added to the
294    \fBpcretest\fP build. In many operating environments with a sytem-installed
295    \fBlibreadline\fP this is sufficient. However, in some environments (e.g.
296    if an unmodified distribution version of readline is in use), some extra
297    configuration may be necessary. The INSTALL file for \fBlibreadline\fP says
298    this:
299    .sp
300      "Readline uses the termcap functions, but does not link with the
301      termcap or curses library itself, allowing applications which link
302      with readline the to choose an appropriate library."
303    .sp
304    If your environment has not been set up so that an appropriate library is
305    automatically included, you may need to add something like
306    .sp
307      LIBS="-ncurses"
308    .sp
309    immediately before the \fBconfigure\fP command.
310  .  .
311  .  .
312  .SH "SEE ALSO"  .SH "SEE ALSO"
313  .rs  .rs
314  .sp  .sp
315  \fBpcreapi\fP(3), \fBpcre_config\fP(3).  \fBpcreapi\fP(3), \fBpcre_config\fP(3).
316  .P  .
317  .in 0  .
318  Last updated: 30 November 2006  .SH AUTHOR
319  .br  .rs
320  Copyright (c) 1997-2006 University of Cambridge.  .sp
321    .nf
322    Philip Hazel
323    University Computing Service
324    Cambridge CB2 3QH, England.
325    .fi
326    .
327    .
328    .SH REVISION
329    .rs
330    .sp
331    .nf
332    Last updated: 17 March 2009
333    Copyright (c) 1997-2009 University of Cambridge.
334    .fi

Legend:
Removed from v.93  
changed lines
  Added in v.392

  ViewVC Help
Powered by ViewVC 1.1.5