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revision 127 by ph10, Mon Mar 19 11:44:45 2007 UTC revision 155 by ph10, Tue Apr 24 13:36:11 2007 UTC
# Line 221  documentation. Line 221  documentation.
221  .SH NEWLINES  .SH NEWLINES
222  .rs  .rs
223  .sp  .sp
224  PCRE supports four different conventions for indicating line breaks in  PCRE supports five different conventions for indicating line breaks in
225  strings: a single CR (carriage return) character, a single LF (linefeed)  strings: a single CR (carriage return) character, a single LF (linefeed)
226  character, the two-character sequence CRLF, or any Unicode newline sequence.  character, the two-character sequence CRLF, any of the three preceding, or any
227  The Unicode newline sequences are the three just mentioned, plus the single  Unicode newline sequence. The Unicode newline sequences are the three just
228  characters VT (vertical tab, U+000B), FF (formfeed, U+000C), NEL (next line,  mentioned, plus the single characters VT (vertical tab, U+000B), FF (formfeed,
229  U+0085), LS (line separator, U+2028), and PS (paragraph separator, U+2029).  U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS
230    (paragraph separator, U+2029).
231  .P  .P
232  Each of the first three conventions is used by at least one operating system as  Each of the first three conventions is used by at least one operating system as
233  its standard newline sequence. When PCRE is built, a default can be specified.  its standard newline sequence. When PCRE is built, a default can be specified.
# Line 264  which it was compiled. Details are given Line 265  which it was compiled. Details are given
265  .\" HREF  .\" HREF
266  \fBpcreprecompile\fP  \fBpcreprecompile\fP
267  .\"  .\"
268  documentation.  documentation. However, compiling a regular expression with one version of PCRE
269    for use with a different version is not guaranteed to work and may cause
270    crashes.
271  .  .
272  .  .
273  .SH "CHECKING BUILD-TIME OPTIONS"  .SH "CHECKING BUILD-TIME OPTIONS"
# Line 297  properties is available; otherwise it is Line 300  properties is available; otherwise it is
300  .sp  .sp
301  The output is an integer whose value specifies the default character sequence  The output is an integer whose value specifies the default character sequence
302  that is recognized as meaning "newline". The four values that are supported  that is recognized as meaning "newline". The four values that are supported
303  are: 10 for LF, 13 for CR, 3338 for CRLF, and -1 for ANY. The default should  are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for ANYCRLF, and -1 for ANY. The
304  normally be the standard sequence for your operating system.  default should normally be the standard sequence for your operating system.
305  .sp  .sp
306    PCRE_CONFIG_LINK_SIZE    PCRE_CONFIG_LINK_SIZE
307  .sp  .sp
# Line 532  occurrences of ^ or $ in a pattern, sett Line 535  occurrences of ^ or $ in a pattern, sett
535    PCRE_NEWLINE_CR    PCRE_NEWLINE_CR
536    PCRE_NEWLINE_LF    PCRE_NEWLINE_LF
537    PCRE_NEWLINE_CRLF    PCRE_NEWLINE_CRLF
538      PCRE_NEWLINE_ANYCRLF
539    PCRE_NEWLINE_ANY    PCRE_NEWLINE_ANY
540  .sp  .sp
541  These options override the default newline definition that was chosen when PCRE  These options override the default newline definition that was chosen when PCRE
542  was built. Setting the first or the second specifies that a newline is  was built. Setting the first or the second specifies that a newline is
543  indicated by a single character (CR or LF, respectively). Setting  indicated by a single character (CR or LF, respectively). Setting
544  PCRE_NEWLINE_CRLF specifies that a newline is indicated by the two-character  PCRE_NEWLINE_CRLF specifies that a newline is indicated by the two-character
545  CRLF sequence. Setting PCRE_NEWLINE_ANY specifies that any Unicode newline  CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies that any of the three
546  sequence should be recognized. The Unicode newline sequences are the three just  preceding sequences should be recognized. Setting PCRE_NEWLINE_ANY specifies
547  mentioned, plus the single characters VT (vertical tab, U+000B), FF (formfeed,  that any Unicode newline sequence should be recognized. The Unicode newline
548  U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS  sequences are the three just mentioned, plus the single characters VT (vertical
549  (paragraph separator, U+2029). The last two are recognized only in UTF-8 mode.  tab, U+000B), FF (formfeed, U+000C), NEL (next line, U+0085), LS (line
550    separator, U+2028), and PS (paragraph separator, U+2029). The last two are
551    recognized only in UTF-8 mode.
552  .P  .P
553  The newline setting in the options word uses three bits that are treated  The newline setting in the options word uses three bits that are treated
554  as a number, giving eight possibilities. Currently only five are used (default  as a number, giving eight possibilities. Currently only six are used (default
555  plus the four values above). This means that if you set more than one newline  plus the five values above). This means that if you set more than one newline
556  option, the combination may or may not be sensible. For example,  option, the combination may or may not be sensible. For example,
557  PCRE_NEWLINE_CR with PCRE_NEWLINE_LF is equivalent to PCRE_NEWLINE_CRLF, but  PCRE_NEWLINE_CR with PCRE_NEWLINE_LF is equivalent to PCRE_NEWLINE_CRLF, but
558  other combinations yield unused numbers and cause an error.  other combinations may yield unused numbers and cause an error.
559  .P  .P
560  The only time that a line break is specially recognized when compiling a  The only time that a line break is specially recognized when compiling a
561  pattern is if PCRE_EXTENDED is set, and an unescaped # outside a character  pattern is if PCRE_EXTENDED is set, and an unescaped # outside a character
# Line 729  bytes is created. Line 735  bytes is created.
735  .SH "LOCALE SUPPORT"  .SH "LOCALE SUPPORT"
736  .rs  .rs
737  .sp  .sp
738  PCRE handles caseless matching, and determines whether characters are letters  PCRE handles caseless matching, and determines whether characters are letters,
739  digits, or whatever, by reference to a set of tables, indexed by character  digits, or whatever, by reference to a set of tables, indexed by character
740  value. When running in UTF-8 mode, this applies only to characters with codes  value. When running in UTF-8 mode, this applies only to characters with codes
741  less than 128. Higher-valued codes never match escapes such as \ew or \ed, but  less than 128. Higher-valued codes never match escapes such as \ew or \ed, but
742  can be tested with \ep if PCRE is built with Unicode character property  can be tested with \ep if PCRE is built with Unicode character property
743  support. The use of locales with Unicode is discouraged.  support. The use of locales with Unicode is discouraged. If you are handling
744  .P  characters with codes greater than 128, you should either use UTF-8 and
745  An internal set of tables is created in the default C locale when PCRE is  Unicode, or use locales, but not try to mix the two.
746  built. This is used when the final argument of \fBpcre_compile()\fP is NULL,  .P
747  and is sufficient for many applications. An alternative set of tables can,  PCRE contains an internal set of tables that are used when the final argument
748  however, be supplied. These may be created in a different locale from the  of \fBpcre_compile()\fP is NULL. These are sufficient for many applications.
749  default. As more and more applications change to using Unicode, the need for  Normally, the internal tables recognize only ASCII characters. However, when
750  this locale support is expected to die away.  PCRE is built, it is possible to cause the internal tables to be rebuilt in the
751    default "C" locale of the local system, which may cause them to be different.
752    .P
753    The internal tables can always be overridden by tables supplied by the
754    application that calls PCRE. These may be created in a different locale from
755    the default. As more and more applications change to using Unicode, the need
756    for this locale support is expected to die away.
757  .P  .P
758  External tables are built by calling the \fBpcre_maketables()\fP function,  External tables are built by calling the \fBpcre_maketables()\fP function,
759  which has no arguments, in the relevant locale. The result can then be passed  which has no arguments, in the relevant locale. The result can then be passed
# Line 754  the following code could be used: Line 766  the following code could be used:
766    tables = pcre_maketables();    tables = pcre_maketables();
767    re = pcre_compile(..., tables);    re = pcre_compile(..., tables);
768  .sp  .sp
769    The locale name "fr_FR" is used on Linux and other Unix-like systems; if you
770    are using Windows, the name for the French locale is "french".
771    .P
772  When \fBpcre_maketables()\fP runs, the tables are built in memory that is  When \fBpcre_maketables()\fP runs, the tables are built in memory that is
773  obtained via \fBpcre_malloc\fP. It is the caller's responsibility to ensure  obtained via \fBpcre_malloc\fP. It is the caller's responsibility to ensure
774  that the memory containing the tables remains available for as long as it is  that the memory containing the tables remains available for as long as it is
# Line 1141  matching time. Line 1156  matching time.
1156    PCRE_NEWLINE_CR    PCRE_NEWLINE_CR
1157    PCRE_NEWLINE_LF    PCRE_NEWLINE_LF
1158    PCRE_NEWLINE_CRLF    PCRE_NEWLINE_CRLF
1159      PCRE_NEWLINE_ANYCRLF
1160    PCRE_NEWLINE_ANY    PCRE_NEWLINE_ANY
1161  .sp  .sp
1162  These options override the newline definition that was chosen or defaulted when  These options override the newline definition that was chosen or defaulted when
# Line 1148  the pattern was compiled. For details, s Line 1164  the pattern was compiled. For details, s
1164  \fBpcre_compile()\fP above. During matching, the newline choice affects the  \fBpcre_compile()\fP above. During matching, the newline choice affects the
1165  behaviour of the dot, circumflex, and dollar metacharacters. It may also alter  behaviour of the dot, circumflex, and dollar metacharacters. It may also alter
1166  the way the match position is advanced after a match failure for an unanchored  the way the match position is advanced after a match failure for an unanchored
1167  pattern. When PCRE_NEWLINE_CRLF or PCRE_NEWLINE_ANY is set, and a match attempt  pattern. When PCRE_NEWLINE_CRLF, PCRE_NEWLINE_ANYCRLF, or PCRE_NEWLINE_ANY is
1168  fails when the current position is at a CRLF sequence, the match position is  set, and a match attempt fails when the current position is at a CRLF sequence,
1169  advanced by two characters instead of one, in other words, to after the CRLF.  the match position is advanced by two characters instead of one, in other
1170    words, to after the CRLF.
1171  .sp  .sp
1172    PCRE_NOTBOL    PCRE_NOTBOL
1173  .sp  .sp
# Line 1587  translation table. Line 1604  translation table.
1604  These functions call \fBpcre_get_stringnumber()\fP, and if it succeeds, they  These functions call \fBpcre_get_stringnumber()\fP, and if it succeeds, they
1605  then call \fBpcre_copy_substring()\fP or \fBpcre_get_substring()\fP, as  then call \fBpcre_copy_substring()\fP or \fBpcre_get_substring()\fP, as
1606  appropriate. \fBNOTE:\fP If PCRE_DUPNAMES is set and there are duplicate names,  appropriate. \fBNOTE:\fP If PCRE_DUPNAMES is set and there are duplicate names,
1607  the behaviour may not be what you want (see the next section).  the behaviour may not be what you want (see the next section).
1608  .  .
1609  .  .
1610  .SH "DUPLICATE SUBPATTERN NAMES"  .SH "DUPLICATE SUBPATTERN NAMES"
# Line 1834  Cambridge CB2 3QH, England. Line 1851  Cambridge CB2 3QH, England.
1851  .rs  .rs
1852  .sp  .sp
1853  .nf  .nf
1854  Last updated: 06 March 2007  Last updated: 24 April 2007
1855  Copyright (c) 1997-2007 University of Cambridge.  Copyright (c) 1997-2007 University of Cambridge.
1856  .fi  .fi
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