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revision 455 by ph10, Tue Sep 22 09:42:11 2009 UTC revision 456 by ph10, Fri Oct 2 08:53:31 2009 UTC
# Line 21  published by O'Reilly, covers regular ex Line 21  published by O'Reilly, covers regular ex
21  description of PCRE's regular expressions is intended as reference material.  description of PCRE's regular expressions is intended as reference material.
22  .P  .P
23  The original operation of PCRE was on strings of one-byte characters. However,  The original operation of PCRE was on strings of one-byte characters. However,
24  there is now also support for UTF-8 character strings. To use this, you must  there is now also support for UTF-8 character strings. To use this,
25  build PCRE to include UTF-8 support, and then call \fBpcre_compile()\fP with  PCRE must be built to include UTF-8 support, and you must call
26  the PCRE_UTF8 option. There is also a special sequence that can be given at the  \fBpcre_compile()\fP or \fBpcre_compile2()\fP with the PCRE_UTF8 option. There
27  start of a pattern:  is also a special sequence that can be given at the start of a pattern:
28  .sp  .sp
29    (*UTF8)    (*UTF8)
30  .sp  .sp
# Line 83  string with one of the following five se Line 83  string with one of the following five se
83    (*ANYCRLF)   any of the three above    (*ANYCRLF)   any of the three above
84    (*ANY)       all Unicode newline sequences    (*ANY)       all Unicode newline sequences
85  .sp  .sp
86  These override the default and the options given to \fBpcre_compile()\fP. For  These override the default and the options given to \fBpcre_compile()\fP or
87  example, on a Unix system where LF is the default newline sequence, the pattern  \fBpcre_compile2()\fP. For example, on a Unix system where LF is the default
88    newline sequence, the pattern
89  .sp  .sp
90    (*CR)a.b    (*CR)a.b
91  .sp  .sp
# Line 206  The \eQ...\eE sequence is recognized bot Line 207  The \eQ...\eE sequence is recognized bot
207  A second use of backslash provides a way of encoding non-printing characters  A second use of backslash provides a way of encoding non-printing characters
208  in patterns in a visible manner. There is no restriction on the appearance of  in patterns in a visible manner. There is no restriction on the appearance of
209  non-printing characters, apart from the binary zero that terminates a pattern,  non-printing characters, apart from the binary zero that terminates a pattern,
210  but when a pattern is being prepared by text editing, it is usually easier to  but when a pattern is being prepared by text editing, it is often easier to use
211  use one of the following escape sequences than the binary character it  one of the following escape sequences than the binary character it represents:
 represents:  
212  .sp  .sp
213    \ea        alarm, that is, the BEL character (hex 07)    \ea        alarm, that is, the BEL character (hex 07)
214    \ecx       "control-x", where x is any character    \ecx       "control-x", where x is any character
# Line 468  one of the following sequences: Line 468  one of the following sequences:
468    (*BSR_ANYCRLF)   CR, LF, or CRLF only    (*BSR_ANYCRLF)   CR, LF, or CRLF only
469    (*BSR_UNICODE)   any Unicode newline sequence    (*BSR_UNICODE)   any Unicode newline sequence
470  .sp  .sp
471  These override the default and the options given to \fBpcre_compile()\fP, but  These override the default and the options given to \fBpcre_compile()\fP or
472  they can be overridden by options given to \fBpcre_exec()\fP. Note that these  \fBpcre_compile2()\fP, but they can be overridden by options given to
473  special settings, which are not Perl-compatible, are recognized only at the  \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP. Note that these special settings,
474  very start of a pattern, and that they must be in upper case. If more than one  which are not Perl-compatible, are recognized only at the very start of a
475  of them is present, the last one is used. They can be combined with a change of  pattern, and that they must be in upper case. If more than one of them is
476  newline convention, for example, a pattern can start with:  present, the last one is used. They can be combined with a change of newline
477    convention, for example, a pattern can start with:
478  .sp  .sp
479    (*ANY)(*BSR_ANYCRLF)    (*ANY)(*BSR_ANYCRLF)
480  .sp  .sp
# Line 740  different meaning, namely the backspace Line 741  different meaning, namely the backspace
741  A word boundary is a position in the subject string where the current character  A word boundary is a position in the subject string where the current character
742  and the previous character do not both match \ew or \eW (i.e. one matches  and the previous character do not both match \ew or \eW (i.e. one matches
743  \ew and the other matches \eW), or the start or end of the string if the  \ew and the other matches \eW), or the start or end of the string if the
744  first or last character matches \ew, respectively.  first or last character matches \ew, respectively. Neither PCRE nor Perl has a
745    separte "start of word" or "end of word" metasequence. However, whatever
746    follows \eb normally determines which it is. For example, the fragment
747    \eba matches "a" at the start of a word.
748  .P  .P
749  The \eA, \eZ, and \ez assertions differ from the traditional circumflex and  The \eA, \eZ, and \ez assertions differ from the traditional circumflex and
750  dollar (described in the next section) in that they only ever match at the very  dollar (described in the next section) in that they only ever match at the very
# Line 872  the lookbehind. Line 876  the lookbehind.
876  .rs  .rs
877  .sp  .sp
878  An opening square bracket introduces a character class, terminated by a closing  An opening square bracket introduces a character class, terminated by a closing
879  square bracket. A closing square bracket on its own is not special. If a  square bracket. A closing square bracket on its own is not special by default.
880  closing square bracket is required as a member of the class, it should be the  However, if the PCRE_JAVASCRIPT_COMPAT option is set, a lone closing square
881  first data character in the class (after an initial circumflex, if present) or  bracket causes a compile-time error. If a closing square bracket is required as
882  escaped with a backslash.  a member of the class, it should be the first data character in the class
883    (after an initial circumflex, if present) or escaped with a backslash.
884  .P  .P
885  A character class matches a single character in the subject. In UTF-8 mode, the  A character class matches a single character in the subject. In UTF-8 mode, the
886  character may occupy more than one byte. A matched character must be in the set  character may be more than one byte long. A matched character must be in the
887  of characters defined by the class, unless the first character in the class  set of characters defined by the class, unless the first character in the class
888  definition is a circumflex, in which case the subject character must not be in  definition is a circumflex, in which case the subject character must not be in
889  the set defined by the class. If a circumflex is actually required as a member  the set defined by the class. If a circumflex is actually required as a member
890  of the class, ensure it is not the first character, or escape it with a  of the class, ensure it is not the first character, or escape it with a
# Line 889  For example, the character class [aeiou] Line 894  For example, the character class [aeiou]
894  [^aeiou] matches any character that is not a lower case vowel. Note that a  [^aeiou] matches any character that is not a lower case vowel. Note that a
895  circumflex is just a convenient notation for specifying the characters that  circumflex is just a convenient notation for specifying the characters that
896  are in the class by enumerating those that are not. A class that starts with a  are in the class by enumerating those that are not. A class that starts with a
897  circumflex is not an assertion: it still consumes a character from the subject  circumflex is not an assertion; it still consumes a character from the subject
898  string, and therefore it fails if the current pointer is at the end of the  string, and therefore it fails if the current pointer is at the end of the
899  string.  string.
900  .P  .P
# Line 903  caseful version would. In UTF-8 mode, PC Line 908  caseful version would. In UTF-8 mode, PC
908  case for characters whose values are less than 128, so caseless matching is  case for characters whose values are less than 128, so caseless matching is
909  always possible. For characters with higher values, the concept of case is  always possible. For characters with higher values, the concept of case is
910  supported if PCRE is compiled with Unicode property support, but not otherwise.  supported if PCRE is compiled with Unicode property support, but not otherwise.
911  If you want to use caseless matching for characters 128 and above, you must  If you want to use caseless matching in UTF8-mode for characters 128 and above,
912  ensure that PCRE is compiled with Unicode property support as well as with  you must ensure that PCRE is compiled with Unicode property support as well as
913  UTF-8 support.  with UTF-8 support.
914  .P  .P
915  Characters that might indicate line breaks are never treated in any special way  Characters that might indicate line breaks are never treated in any special way
916  when matching character classes, whatever line-ending sequence is in use, and  when matching character classes, whatever line-ending sequence is in use, and
# Line 1132  is reached, an option setting in one bra Line 1137  is reached, an option setting in one bra
1137  the above patterns match "SUNDAY" as well as "Saturday".  the above patterns match "SUNDAY" as well as "Saturday".
1138  .  .
1139  .  .
1140    .\" HTML <a name="dupsubpatternnumber"></a>
1141  .SH "DUPLICATE SUBPATTERN NUMBERS"  .SH "DUPLICATE SUBPATTERN NUMBERS"
1142  .rs  .rs
1143  .sp  .sp
# Line 1157  stored. Line 1163  stored.
1163    / ( a )  (?| x ( y ) z | (p (q) r) | (t) u (v) ) ( z ) /x    / ( a )  (?| x ( y ) z | (p (q) r) | (t) u (v) ) ( z ) /x
1164    # 1            2         2  3        2     3     4    # 1            2         2  3        2     3     4
1165  .sp  .sp
1166  A backreference or a recursive call to a numbered subpattern always refers to  A backreference to a numbered subpattern uses the most recent value that is set
1167  the first one in the pattern with the given number.  for that number by any subpattern. The following pattern matches "abcabc" or
1168    "defdef":
1169    .sp
1170      /(?|(abc)|(def))\1/
1171    .sp
1172    In contrast, a recursive or "subroutine" call to a numbered subpattern always
1173    refers to the first one in the pattern with the given number. The following
1174    pattern matches "abcabc" or "defabc":
1175    .sp
1176      /(?|(abc)|(def))(?1)/
1177    .sp
1178  .P  .P
1179  An alternative approach to using this "branch reset" feature is to use  An alternative approach to using the "branch reset" feature is to use
1180  duplicate named subpatterns, as described in the next section.  duplicate named subpatterns, as described in the next section.
1181  .  .
1182  .  .
# Line 1247  items: Line 1263  items:
1263    a character class    a character class
1264    a back reference (see next section)    a back reference (see next section)
1265    a parenthesized subpattern (unless it is an assertion)    a parenthesized subpattern (unless it is an assertion)
1266      a recursive or "subroutine" call to a subpattern
1267  .sp  .sp
1268  The general repetition quantifier specifies a minimum and maximum number of  The general repetition quantifier specifies a minimum and maximum number of
1269  permitted matches, by giving the two numbers in curly brackets (braces),  permitted matches, by giving the two numbers in curly brackets (braces),
# Line 1568  after the reference. Line 1585  after the reference.
1585  .P  .P
1586  There may be more than one back reference to the same subpattern. If a  There may be more than one back reference to the same subpattern. If a
1587  subpattern has not actually been used in a particular match, any back  subpattern has not actually been used in a particular match, any back
1588  references to it always fail. For example, the pattern  references to it always fail by default. For example, the pattern
1589  .sp  .sp
1590    (a|(bc))\e2    (a|(bc))\e2
1591  .sp  .sp
1592  always fails if it starts to match "a" rather than "bc". Because there may be  always fails if it starts to match "a" rather than "bc". However, if the
1593  many capturing parentheses in a pattern, all digits following the backslash are  PCRE_JAVASCRIPT_COMPAT option is set at compile time, a back reference to an
1594  taken as part of a potential back reference number. If the pattern continues  unset value matches an empty string.
1595  with a digit character, some delimiter must be used to terminate the back  .P
1596  reference. If the PCRE_EXTENDED option is set, this can be whitespace.  Because there may be many capturing parentheses in a pattern, all digits
1597  Otherwise an empty comment (see  following a backslash are taken as part of a potential back reference number.
1598    If the pattern continues with a digit character, some delimiter must be used to
1599    terminate the back reference. If the PCRE_EXTENDED option is set, this can be
1600    whitespace. Otherwise, the \eg{ syntax or an empty comment (see
1601  .\" HTML <a href="#comments">  .\" HTML <a href="#comments">
1602  .\" </a>  .\" </a>
1603  "Comments"  "Comments"
# Line 1650  lookbehind assertion is needed to achiev Line 1670  lookbehind assertion is needed to achiev
1670  If you want to force a matching failure at some point in a pattern, the most  If you want to force a matching failure at some point in a pattern, the most
1671  convenient way to do it is with (?!) because an empty string always matches, so  convenient way to do it is with (?!) because an empty string always matches, so
1672  an assertion that requires there not to be an empty string must always fail.  an assertion that requires there not to be an empty string must always fail.
1673    The Perl 5.10 backtracking control verb (*FAIL) or (*F) is essentially a
1674    synonym for (?!).
1675  .  .
1676  .  .
1677  .\" HTML <a name="lookbehind"></a>  .\" HTML <a name="lookbehind"></a>
# Line 1716  Recursion, Line 1738  Recursion,
1738  however, is not supported.  however, is not supported.
1739  .P  .P
1740  Possessive quantifiers can be used in conjunction with lookbehind assertions to  Possessive quantifiers can be used in conjunction with lookbehind assertions to
1741  specify efficient matching at the end of the subject string. Consider a simple  specify efficient matching of fixed-length strings at the end of subject
1742  pattern such as  strings. Consider a simple pattern such as
1743  .sp  .sp
1744    abcd$    abcd$
1745  .sp  .sp
# Line 1781  characters that are not "999". Line 1803  characters that are not "999".
1803  .sp  .sp
1804  It is possible to cause the matching process to obey a subpattern  It is possible to cause the matching process to obey a subpattern
1805  conditionally or to choose between two alternative subpatterns, depending on  conditionally or to choose between two alternative subpatterns, depending on
1806  the result of an assertion, or whether a previous capturing subpattern matched  the result of an assertion, or whether a specific capturing subpattern has
1807  or not. The two possible forms of conditional subpattern are  already been matched. The two possible forms of conditional subpattern are:
1808  .sp  .sp
1809    (?(condition)yes-pattern)    (?(condition)yes-pattern)
1810    (?(condition)yes-pattern|no-pattern)    (?(condition)yes-pattern|no-pattern)
# Line 1798  recursion, a pseudo-condition called DEF Line 1820  recursion, a pseudo-condition called DEF
1820  .rs  .rs
1821  .sp  .sp
1822  If the text between the parentheses consists of a sequence of digits, the  If the text between the parentheses consists of a sequence of digits, the
1823  condition is true if the capturing subpattern of that number has previously  condition is true if a capturing subpattern of that number has previously
1824  matched. An alternative notation is to precede the digits with a plus or minus  matched. If there is more than one capturing subpattern with the same number
1825  sign. In this case, the subpattern number is relative rather than absolute.  (see the earlier
1826  The most recently opened parentheses can be referenced by (?(-1), the next most  .\"
1827  recent by (?(-2), and so on. In looping constructs it can also make sense to  .\" HTML <a href="#recursion">
1828  refer to subsequent groups with constructs such as (?(+2).  .\" </a>
1829    section about duplicate subpattern numbers),
1830    .\"
1831    the condition is true if any of them have been set. An alternative notation is
1832    to precede the digits with a plus or minus sign. In this case, the subpattern
1833    number is relative rather than absolute. The most recently opened parentheses
1834    can be referenced by (?(-1), the next most recent by (?(-2), and so on. In
1835    looping constructs it can also make sense to refer to subsequent groups with
1836    constructs such as (?(+2).
1837  .P  .P
1838  Consider the following pattern, which contains non-significant white space to  Consider the following pattern, which contains non-significant white space to
1839  make it more readable (assume the PCRE_EXTENDED option) and to divide it into  make it more readable (assume the PCRE_EXTENDED option) and to divide it into
# Line 1855  letter R, for example: Line 1885  letter R, for example:
1885  .sp  .sp
1886    (?(R3)...) or (?(R&name)...)    (?(R3)...) or (?(R&name)...)
1887  .sp  .sp
1888  the condition is true if the most recent recursion is into the subpattern whose  the condition is true if the most recent recursion is into a subpattern whose
1889  number or name is given. This condition does not check the entire recursion  number or name is given. This condition does not check the entire recursion
1890  stack.  stack.
1891  .P  .P
# Line 1887  written like this (ignore whitespace and Line 1917  written like this (ignore whitespace and
1917  The first part of the pattern is a DEFINE group inside which a another group  The first part of the pattern is a DEFINE group inside which a another group
1918  named "byte" is defined. This matches an individual component of an IPv4  named "byte" is defined. This matches an individual component of an IPv4
1919  address (a number less than 256). When matching takes place, this part of the  address (a number less than 256). When matching takes place, this part of the
1920  pattern is skipped because DEFINE acts like a false condition.  pattern is skipped because DEFINE acts like a false condition. The rest of the
1921  .P  pattern uses references to the named group to match the four dot-separated
1922  The rest of the pattern uses references to the named group to match the four  components of an IPv4 address, insisting on a word boundary at each end.
 dot-separated components of an IPv4 address, insisting on a word boundary at  
 each end.  
1923  .  .
1924  .SS "Assertion conditions"  .SS "Assertion conditions"
1925  .rs  .rs
# Line 1963  a recursive call of the entire regular e Line 1991  a recursive call of the entire regular e
1991  This PCRE pattern solves the nested parentheses problem (assume the  This PCRE pattern solves the nested parentheses problem (assume the
1992  PCRE_EXTENDED option is set so that white space is ignored):  PCRE_EXTENDED option is set so that white space is ignored):
1993  .sp  .sp
1994    \e( ( (?>[^()]+) | (?R) )* \e)    \e( ( [^()]++ | (?R) )* \e)
1995  .sp  .sp
1996  First it matches an opening parenthesis. Then it matches any number of  First it matches an opening parenthesis. Then it matches any number of
1997  substrings which can either be a sequence of non-parentheses, or a recursive  substrings which can either be a sequence of non-parentheses, or a recursive
1998  match of the pattern itself (that is, a correctly parenthesized substring).  match of the pattern itself (that is, a correctly parenthesized substring).
1999  Finally there is a closing parenthesis.  Finally there is a closing parenthesis. Note the use of a possessive quantifier
2000    to avoid backtracking into sequences of non-parentheses.
2001  .P  .P
2002  If this were part of a larger pattern, you would not want to recurse the entire  If this were part of a larger pattern, you would not want to recurse the entire
2003  pattern, so instead you could use this:  pattern, so instead you could use this:
2004  .sp  .sp
2005    ( \e( ( (?>[^()]+) | (?1) )* \e) )    ( \e( ( [^()]++ | (?1) )* \e) )
2006  .sp  .sp
2007  We have put the pattern into parentheses, and caused the recursion to refer to  We have put the pattern into parentheses, and caused the recursion to refer to
2008  them instead of the whole pattern.  them instead of the whole pattern.
2009  .P  .P
2010  In a larger pattern, keeping track of parenthesis numbers can be tricky. This  In a larger pattern, keeping track of parenthesis numbers can be tricky. This
2011  is made easier by the use of relative references. (A Perl 5.10 feature.)  is made easier by the use of relative references (a Perl 5.10 feature).
2012  Instead of (?1) in the pattern above you can write (?-2) to refer to the second  Instead of (?1) in the pattern above you can write (?-2) to refer to the second
2013  most recently opened parentheses preceding the recursion. In other words, a  most recently opened parentheses preceding the recursion. In other words, a
2014  negative number counts capturing parentheses leftwards from the point at which  negative number counts capturing parentheses leftwards from the point at which
# Line 1998  An alternative approach is to use named Line 2027  An alternative approach is to use named
2027  for this is (?&name); PCRE's earlier syntax (?P>name) is also supported. We  for this is (?&name); PCRE's earlier syntax (?P>name) is also supported. We
2028  could rewrite the above example as follows:  could rewrite the above example as follows:
2029  .sp  .sp
2030    (?<pn> \e( ( (?>[^()]+) | (?&pn) )* \e) )    (?<pn> \e( ( [^()]++ | (?&pn) )* \e) )
2031  .sp  .sp
2032  If there is more than one subpattern with the same name, the earliest one is  If there is more than one subpattern with the same name, the earliest one is
2033  used.  used.
2034  .P  .P
2035  This particular example pattern that we have been looking at contains nested  This particular example pattern that we have been looking at contains nested
2036  unlimited repeats, and so the use of atomic grouping for matching strings of  unlimited repeats, and so the use of a possessive quantifier for matching
2037  non-parentheses is important when applying the pattern to strings that do not  strings of non-parentheses is important when applying the pattern to strings
2038  match. For example, when this pattern is applied to  that do not match. For example, when this pattern is applied to
2039  .sp  .sp
2040    (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa()    (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa()
2041  .sp  .sp
2042  it yields "no match" quickly. However, if atomic grouping is not used,  it yields "no match" quickly. However, if a possessive quantifier is not used,
2043  the match runs for a very long time indeed because there are so many different  the match runs for a very long time indeed because there are so many different
2044  ways the + and * repeats can carve up the subject, and all have to be tested  ways the + and * repeats can carve up the subject, and all have to be tested
2045  before failure can be reported.  before failure can be reported.
# Line 2029  documentation). If the pattern above is Line 2058  documentation). If the pattern above is
2058  the value for the capturing parentheses is "ef", which is the last value taken  the value for the capturing parentheses is "ef", which is the last value taken
2059  on at the top level. If additional parentheses are added, giving  on at the top level. If additional parentheses are added, giving
2060  .sp  .sp
2061    \e( ( ( (?>[^()]+) | (?R) )* ) \e)    \e( ( ( [^()]++ | (?R) )* ) \e)
2062       ^                        ^       ^                        ^
2063       ^                        ^       ^                        ^
2064  .sp  .sp
# Line 2113  the use of the possessive quantifier *+ Line 2142  the use of the possessive quantifier *+
2142  non-word characters. Without this, PCRE takes a great deal longer (ten times or  non-word characters. Without this, PCRE takes a great deal longer (ten times or
2143  more) to match typical phrases, and Perl takes so long that you think it has  more) to match typical phrases, and Perl takes so long that you think it has
2144  gone into a loop.  gone into a loop.
2145    .P
2146    \fBWARNING\fP: The palindrome-matching patterns above work only if the subject
2147    string does not start with a palindrome that is shorter than the entire string.
2148    For example, although "abcba" is correctly matched, if the subject is "ababa",
2149    PCRE finds the palindrome "aba" at the start, then fails at top level because
2150    the end of the string does not follow. Once again, it cannot jump back into the
2151    recursion to try other alternatives, so the entire match fails.
2152  .  .
2153  .  .
2154  .\" HTML <a name="subpatternsassubroutines"></a>  .\" HTML <a name="subpatternsassubroutines"></a>
# Line 2248  The following verbs act as soon as they Line 2284  The following verbs act as soon as they
2284  .sp  .sp
2285  This verb causes the match to end successfully, skipping the remainder of the  This verb causes the match to end successfully, skipping the remainder of the
2286  pattern. When inside a recursion, only the innermost pattern is ended  pattern. When inside a recursion, only the innermost pattern is ended
2287  immediately. If the (*ACCEPT) is inside capturing parentheses, the data so far  immediately. If (*ACCEPT) is inside capturing parentheses, the data so far is
2288  is captured. (This feature was added to PCRE at release 8.00.) For example:  captured. (This feature was added to PCRE at release 8.00.) For example:
2289  .sp  .sp
2290    A((?:A|B(*ACCEPT)|C)D)    A((?:A|B(*ACCEPT)|C)D)
2291  .sp  .sp
# Line 2280  The verbs differ in exactly what kind of Line 2316  The verbs differ in exactly what kind of
2316  .sp  .sp
2317  This verb causes the whole match to fail outright if the rest of the pattern  This verb causes the whole match to fail outright if the rest of the pattern
2318  does not match. Even if the pattern is unanchored, no further attempts to find  does not match. Even if the pattern is unanchored, no further attempts to find
2319  a match by advancing the start point take place. Once (*COMMIT) has been  a match by advancing the starting point take place. Once (*COMMIT) has been
2320  passed, \fBpcre_exec()\fP is committed to finding a match at the current  passed, \fBpcre_exec()\fP is committed to finding a match at the current
2321  starting point, or not at all. For example:  starting point, or not at all. For example:
2322  .sp  .sp
# Line 2312  was matched leading up to it cannot be p Line 2348  was matched leading up to it cannot be p
2348  If the subject is "aaaac...", after the first match attempt fails (starting at  If the subject is "aaaac...", after the first match attempt fails (starting at
2349  the first character in the string), the starting point skips on to start the  the first character in the string), the starting point skips on to start the
2350  next attempt at "c". Note that a possessive quantifer does not have the same  next attempt at "c". Note that a possessive quantifer does not have the same
2351  effect in this example; although it would suppress backtracking during the  effect as this example; although it would suppress backtracking during the
2352  first match attempt, the second attempt would start at the second character  first match attempt, the second attempt would start at the second character
2353  instead of skipping on to "c".  instead of skipping on to "c".
2354  .sp  .sp
# Line 2334  is used outside of any alternation, it a Line 2370  is used outside of any alternation, it a
2370  .SH "SEE ALSO"  .SH "SEE ALSO"
2371  .rs  .rs
2372  .sp  .sp
2373  \fBpcreapi\fP(3), \fBpcrecallout\fP(3), \fBpcrematching\fP(3), \fBpcre\fP(3).  \fBpcreapi\fP(3), \fBpcrecallout\fP(3), \fBpcrematching\fP(3),
2374    \fBpcresyntax\fP(3), \fBpcre\fP(3).
2375  .  .
2376  .  .
2377  .SH AUTHOR  .SH AUTHOR
# Line 2351  Cambridge CB2 3QH, England. Line 2388  Cambridge CB2 3QH, England.
2388  .rs  .rs
2389  .sp  .sp
2390  .nf  .nf
2391  Last updated: 22 September 2009  Last updated: 30 September 2009
2392  Copyright (c) 1997-2009 University of Cambridge.  Copyright (c) 1997-2009 University of Cambridge.
2393  .fi  .fi

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