/[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 96 by nigel, Fri Mar 2 13:10:43 2007 UTC revision 461 by ph10, Mon Oct 5 10:59:35 2009 UTC
# Line 1  Line 1 
1  .TH PCREBUILD 3  .TH PCREBUILD 3
2  .SH NAME  .SH NAME
3  PCRE - Perl-compatible regular expressions  PCRE - Perl-compatible regular expressions
4    .
5    .
6  .SH "PCRE BUILD-TIME OPTIONS"  .SH "PCRE BUILD-TIME OPTIONS"
7  .rs  .rs
8  .sp  .sp
9  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
10  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
11  options to the \fBconfigure\fP script that is run before the \fBmake\fP  the optional features are selected or deselected by providing options to
12  command. The complete list of options for \fBconfigure\fP (which includes the  \fBconfigure\fP before running the \fBmake\fP command. However, the same
13  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
14  obtained by running  the GUI facility of \fBcmake-gui\fP if you are using \fBCMake\fP instead of
15    \fBconfigure\fP to build PCRE.
16    .P
17    There is a lot more information about building PCRE in non-Unix-like
18    environments in the file called \fINON_UNIX_USE\fP, which is part of the PCRE
19    distribution. You should consult this file as well as the \fIREADME\fP file if
20    you are building in a non-Unix-like environment.
21    .P
22    The complete list of options for \fBconfigure\fP (which includes the standard
23    ones such as the selection of the installation directory) can be obtained by
24    running
25  .sp  .sp
26    ./configure --help    ./configure --help
27  .sp  .sp
28  The following sections describe certain options whose names begin with --enable  The following sections include descriptions of options whose names begin with
29  or --disable. These settings specify changes to the defaults for the  --enable or --disable. These settings specify changes to the defaults for the
30  \fBconfigure\fP command. Because of the way that \fBconfigure\fP works,  \fBconfigure\fP command. Because of the way that \fBconfigure\fP works,
31  --enable and --disable always come in pairs, so the complementary option always  --enable and --disable always come in pairs, so the complementary option always
32  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.
33  .  .
34    .
35  .SH "C++ SUPPORT"  .SH "C++ SUPPORT"
36  .rs  .rs
37  .sp  .sp
# Line 30  for PCRE. You can disable this by adding Line 43  for PCRE. You can disable this by adding
43  .sp  .sp
44  to the \fBconfigure\fP command.  to the \fBconfigure\fP command.
45  .  .
46    .
47  .SH "UTF-8 SUPPORT"  .SH "UTF-8 SUPPORT"
48  .rs  .rs
49  .sp  .sp
50  To build PCRE with support for UTF-8 character strings, add  To build PCRE with support for UTF-8 Unicode character strings, add
51  .sp  .sp
52    --enable-utf8    --enable-utf8
53  .sp  .sp
54  to the \fBconfigure\fP command. Of itself, this does not make PCRE treat  to the \fBconfigure\fP command. Of itself, this does not make PCRE treat
55  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
56  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
57  function.  or \fBpcre_compile2()\fP functions.
58    .P
59    If you set --enable-utf8 when compiling in an EBCDIC environment, PCRE expects
60    its input to be either ASCII or UTF-8 (depending on the runtime option). It is
61    not possible to support both EBCDIC and UTF-8 codes in the same version of the
62    library. Consequently, --enable-utf8 and --enable-ebcdic are mutually
63    exclusive.
64    .
65  .  .
66  .SH "UNICODE CHARACTER PROPERTY SUPPORT"  .SH "UNICODE CHARACTER PROPERTY SUPPORT"
67  .rs  .rs
# Line 56  character properties, you must add Line 77  character properties, you must add
77  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
78  not explicitly requested it.  not explicitly requested it.
79  .P  .P
80  Including Unicode property support adds around 90K of tables to the PCRE  Including Unicode property support adds around 30K of tables to the PCRE
81  library, approximately doubling its size. Only the general category properties  library. Only the general category properties such as \fILu\fP and \fINd\fP are
82  such as \fILu\fP and \fINd\fP are supported. Details are given in the  supported. Details are given in the
83  .\" HREF  .\" HREF
84  \fBpcrepattern\fP  \fBpcrepattern\fP
85  .\"  .\"
86  documentation.  documentation.
87  .  .
88    .
89  .SH "CODE VALUE OF NEWLINE"  .SH "CODE VALUE OF NEWLINE"
90  .rs  .rs
91  .sp  .sp
92  By default, PCRE interprets character 10 (linefeed, LF) as indicating the end  By default, PCRE interprets the linefeed (LF) character as indicating the end
93  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
94  compile PCRE to use character 13 (carriage return, CR) instead, by adding  compile PCRE to use carriage return (CR) instead, by adding
95  .sp  .sp
96    --enable-newline-is-cr    --enable-newline-is-cr
97  .sp  .sp
# Line 83  character sequence CRLF. If you want thi Line 105  character sequence CRLF. If you want thi
105  .sp  .sp
106  to the \fBconfigure\fP command. There is a fourth option, specified by  to the \fBconfigure\fP command. There is a fourth option, specified by
107  .sp  .sp
108      --enable-newline-is-anycrlf
109    .sp
110    which causes PCRE to recognize any of the three sequences CR, LF, or CRLF as
111    indicating a line ending. Finally, a fifth option, specified by
112    .sp
113    --enable-newline-is-any    --enable-newline-is-any
114  .sp  .sp
115  which causes PCRE to recognize any Unicode newline sequence.  causes PCRE to recognize any Unicode newline sequence.
116  .P  .P
117  Whatever line ending convention is selected when PCRE is built can be  Whatever line ending convention is selected when PCRE is built can be
118  overridden when the library functions are called. At build time it is  overridden when the library functions are called. At build time it is
119  conventional to use the standard for your operating system.  conventional to use the standard for your operating system.
120  .  .
121    .
122    .SH "WHAT \eR MATCHES"
123    .rs
124    .sp
125    By default, the sequence \eR in a pattern matches any Unicode newline sequence,
126    whatever has been selected as the line ending sequence. If you specify
127    .sp
128      --enable-bsr-anycrlf
129    .sp
130    the default is changed so that \eR matches only CR, LF, or CRLF. Whatever is
131    selected when PCRE is built can be overridden when the library functions are
132    called.
133    .
134    .
135  .SH "BUILDING SHARED AND STATIC LIBRARIES"  .SH "BUILDING SHARED AND STATIC LIBRARIES"
136  .rs  .rs
137  .sp  .sp
# Line 102  Unix libraries by default. You can suppr Line 143  Unix libraries by default. You can suppr
143  .sp  .sp
144  to the \fBconfigure\fP command, as required.  to the \fBconfigure\fP command, as required.
145  .  .
146    .
147  .SH "POSIX MALLOC USAGE"  .SH "POSIX MALLOC USAGE"
148  .rs  .rs
149  .sp  .sp
# Line 121  such as Line 163  such as
163  .sp  .sp
164  to the \fBconfigure\fP command.  to the \fBconfigure\fP command.
165  .  .
166    .
167  .SH "HANDLING VERY LARGE PATTERNS"  .SH "HANDLING VERY LARGE PATTERNS"
168  .rs  .rs
169  .sp  .sp
# Line 129  another (for example, from an opening pa Line 172  another (for example, from an opening pa
172  metacharacter). By default, two-byte values are used for these offsets, leading  metacharacter). By default, two-byte values are used for these offsets, leading
173  to a maximum size for a compiled pattern of around 64K. This is sufficient to  to a maximum size for a compiled pattern of around 64K. This is sufficient to
174  handle all but the most gigantic patterns. Nevertheless, some people do want to  handle all but the most gigantic patterns. Nevertheless, some people do want to
175  process enormous patterns, so it is possible to compile PCRE to use three-byte  process truyl enormous patterns, so it is possible to compile PCRE to use
176  or four-byte offsets by adding a setting such as  three-byte or four-byte offsets by adding a setting such as
177  .sp  .sp
178    --with-link-size=3    --with-link-size=3
179  .sp  .sp
180  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
181  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
182  additional bytes when handling them.  additional bytes when handling them.
183  .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.  
184  .  .
185  .SH "AVOIDING EXCESSIVE STACK USAGE"  .SH "AVOIDING EXCESSIVE STACK USAGE"
186  .rs  .rs
# Line 163  build a version of PCRE that works this Line 203  build a version of PCRE that works this
203  .sp  .sp
204  to the \fBconfigure\fP command. With this configuration, PCRE will use the  to the \fBconfigure\fP command. With this configuration, PCRE will use the
205  \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
206  management functions. Separate functions are provided because the usage is very  management functions. By default these point to \fBmalloc()\fP and
207  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
208  always freed in reverse order. A calling program might be able to implement  used instead.
209  optimized functions that perform better than the standard \fBmalloc()\fP and  .P
210  \fBfree()\fP functions. PCRE runs noticeably more slowly when built in this  Separate functions are provided rather than using \fBpcre_malloc\fP and
211  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
212  relevant for the the \fBpcre_dfa_exec()\fP function.  requested are always the same, and the blocks are always freed in reverse
213    order. A calling program might be able to implement optimized functions that
214    perform better than \fBmalloc()\fP and \fBfree()\fP. PCRE runs noticeably more
215    slowly when built in this way. This option affects only the \fBpcre_exec()\fP
216    function; it is not relevant for \fBpcre_dfa_exec()\fP.
217    .
218  .  .
219  .SH "LIMITING PCRE RESOURCE USAGE"  .SH "LIMITING PCRE RESOURCE USAGE"
220  .rs  .rs
# Line 202  constraints. However, you can set a lowe Line 247  constraints. However, you can set a lowe
247  .sp  .sp
248  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.
249  .  .
250    .
251    .SH "CREATING CHARACTER TABLES AT BUILD TIME"
252    .rs
253    .sp
254    PCRE uses fixed tables for processing characters whose code values are less
255    than 256. By default, PCRE is built with a set of tables that are distributed
256    in the file \fIpcre_chartables.c.dist\fP. These tables are for ASCII codes
257    only. If you add
258    .sp
259      --enable-rebuild-chartables
260    .sp
261    to the \fBconfigure\fP command, the distributed tables are no longer used.
262    Instead, a program called \fBdftables\fP is compiled and run. This outputs the
263    source for new set of tables, created in the default locale of your C runtime
264    system. (This method of replacing the tables does not work if you are cross
265    compiling, because \fBdftables\fP is run on the local host. If you need to
266    create alternative tables when cross compiling, you will have to do so "by
267    hand".)
268    .
269    .
270  .SH "USING EBCDIC CODE"  .SH "USING EBCDIC CODE"
271  .rs  .rs
272  .sp  .sp
273  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
274  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
275  compiled to run in an EBCDIC environment by adding  most computer operating systems. PCRE can, however, be compiled to run in an
276    EBCDIC environment by adding
277  .sp  .sp
278    --enable-ebcdic    --enable-ebcdic
279  .sp  .sp
280  to the \fBconfigure\fP command.  to the \fBconfigure\fP command. This setting implies
281    --enable-rebuild-chartables. You should only use it if you know that you are in
282    an EBCDIC environment (for example, an IBM mainframe operating system). The
283    --enable-ebcdic option is incompatible with --enable-utf8.
284    .
285    .
286    .SH "PCREGREP OPTIONS FOR COMPRESSED FILE SUPPORT"
287    .rs
288    .sp
289    By default, \fBpcregrep\fP reads all files as plain text. You can build it so
290    that it recognizes files whose names end in \fB.gz\fP or \fB.bz2\fP, and reads
291    them with \fBlibz\fP or \fBlibbz2\fP, respectively, by adding one or both of
292    .sp
293      --enable-pcregrep-libz
294      --enable-pcregrep-libbz2
295    .sp
296    to the \fBconfigure\fP command. These options naturally require that the
297    relevant libraries are installed on your system. Configuration will fail if
298    they are not.
299    .
300    .
301    .SH "PCRETEST OPTION FOR LIBREADLINE SUPPORT"
302    .rs
303    .sp
304    If you add
305    .sp
306      --enable-pcretest-libreadline
307    .sp
308    to the \fBconfigure\fP command, \fBpcretest\fP is linked with the
309    \fBlibreadline\fP library, and when its input is from a terminal, it reads it
310    using the \fBreadline()\fP function. This provides line-editing and history
311    facilities. Note that \fBlibreadline\fP is GPL-licensed, so if you distribute a
312    binary of \fBpcretest\fP linked in this way, there may be licensing issues.
313    .P
314    Setting this option causes the \fB-lreadline\fP option to be added to the
315    \fBpcretest\fP build. In many operating environments with a sytem-installed
316    \fBlibreadline\fP this is sufficient. However, in some environments (e.g.
317    if an unmodified distribution version of readline is in use), some extra
318    configuration may be necessary. The INSTALL file for \fBlibreadline\fP says
319    this:
320    .sp
321      "Readline uses the termcap functions, but does not link with the
322      termcap or curses library itself, allowing applications which link
323      with readline the to choose an appropriate library."
324    .sp
325    If your environment has not been set up so that an appropriate library is
326    automatically included, you may need to add something like
327    .sp
328      LIBS="-ncurses"
329    .sp
330    immediately before the \fBconfigure\fP command.
331  .  .
332  .  .
333  .SH "SEE ALSO"  .SH "SEE ALSO"
334  .rs  .rs
335  .sp  .sp
336  \fBpcreapi\fP(3), \fBpcre_config\fP(3).  \fBpcreapi\fP(3), \fBpcre_config\fP(3).
337  .P  .
338  .in 0  .
339  Last updated: 30 November 2006  .SH AUTHOR
340  .br  .rs
341  Copyright (c) 1997-2006 University of Cambridge.  .sp
342    .nf
343    Philip Hazel
344    University Computing Service
345    Cambridge CB2 3QH, England.
346    .fi
347    .
348    .
349    .SH REVISION
350    .rs
351    .sp
352    .nf
353    Last updated: 29 September 2009
354    Copyright (c) 1997-2009 University of Cambridge.
355    .fi

Legend:
Removed from v.96  
changed lines
  Added in v.461

  ViewVC Help
Powered by ViewVC 1.1.5