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revision 292 by ph10, Thu Dec 27 09:27:23 2007 UTC revision 440 by ph10, Wed Sep 9 10:14:40 2009 UTC
# Line 135  Applications can use these to include su Line 135  Applications can use these to include su
135  The functions \fBpcre_compile()\fP, \fBpcre_compile2()\fP, \fBpcre_study()\fP,  The functions \fBpcre_compile()\fP, \fBpcre_compile2()\fP, \fBpcre_study()\fP,
136  and \fBpcre_exec()\fP are used for compiling and matching regular expressions  and \fBpcre_exec()\fP are used for compiling and matching regular expressions
137  in a Perl-compatible manner. A sample program that demonstrates the simplest  in a Perl-compatible manner. A sample program that demonstrates the simplest
138  way of using them is provided in the file called \fIpcredemo.c\fP in the source  way of using them is provided in the file called \fIpcredemo.c\fP in the PCRE
139  distribution. The  source distribution. A listing of this program is given in the
140    .\" HREF
141    \fBpcredemo\fP
142    .\"
143    documentation, and the
144  .\" HREF  .\" HREF
145  \fBpcresample\fP  \fBpcresample\fP
146  .\"  .\"
147  documentation describes how to run it.  documentation describes how to compile and run it.
148  .P  .P
149  A second matching function, \fBpcre_dfa_exec()\fP, which is not  A second matching function, \fBpcre_dfa_exec()\fP, which is not
150  Perl-compatible, is also provided. This uses a different algorithm for the  Perl-compatible, is also provided. This uses a different algorithm for the
151  matching. The alternative algorithm finds all possible matches (at a given  matching. The alternative algorithm finds all possible matches (at a given
152  point in the subject), and scans the subject just once. However, this algorithm  point in the subject), and scans the subject just once (unless there are
153  does not return captured substrings. A description of the two matching  lookbehind assertions). However, this algorithm does not return captured
154  algorithms and their advantages and disadvantages is given in the  substrings. A description of the two matching algorithms and their advantages
155    and disadvantages is given in the
156  .\" HREF  .\" HREF
157  \fBpcrematching\fP  \fBpcrematching\fP
158  .\"  .\"
# Line 317  properties is available; otherwise it is Line 322  properties is available; otherwise it is
322  .sp  .sp
323  The output is an integer whose value specifies the default character sequence  The output is an integer whose value specifies the default character sequence
324  that is recognized as meaning "newline". The four values that are supported  that is recognized as meaning "newline". The four values that are supported
325  are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for ANYCRLF, and -1 for ANY. The  are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for ANYCRLF, and -1 for ANY.
326  default should normally be the standard sequence for your operating system.  Though they are derived from ASCII, the same values are returned in EBCDIC
327    environments. The default should normally correspond to the standard sequence
328    for your operating system.
329  .sp  .sp
330    PCRE_CONFIG_BSR    PCRE_CONFIG_BSR
331  .sp  .sp
# Line 347  documentation. Line 354  documentation.
354  .sp  .sp
355    PCRE_CONFIG_MATCH_LIMIT    PCRE_CONFIG_MATCH_LIMIT
356  .sp  .sp
357  The output is an integer that gives the default limit for the number of  The output is a long integer that gives the default limit for the number of
358  internal matching function calls in a \fBpcre_exec()\fP execution. Further  internal matching function calls in a \fBpcre_exec()\fP execution. Further
359  details are given with \fBpcre_exec()\fP below.  details are given with \fBpcre_exec()\fP below.
360  .sp  .sp
361    PCRE_CONFIG_MATCH_LIMIT_RECURSION    PCRE_CONFIG_MATCH_LIMIT_RECURSION
362  .sp  .sp
363  The output is an integer that gives the default limit for the depth of  The output is a long integer that gives the default limit for the depth of
364  recursion when calling the internal matching function in a \fBpcre_exec()\fP  recursion when calling the internal matching function in a \fBpcre_exec()\fP
365  execution. Further details are given with \fBpcre_exec()\fP below.  execution. Further details are given with \fBpcre_exec()\fP below.
366  .sp  .sp
# Line 404  argument, which is an address (see below Line 411  argument, which is an address (see below
411  .P  .P
412  The \fIoptions\fP argument contains various bit settings that affect the  The \fIoptions\fP argument contains various bit settings that affect the
413  compilation. It should be zero if no options are required. The available  compilation. It should be zero if no options are required. The available
414  options are described below. Some of them, in particular, those that are  options are described below. Some of them (in particular, those that are
415  compatible with Perl, can also be set and unset from within the pattern (see  compatible with Perl, but also some others) can also be set and unset from
416  the detailed description in the  within the pattern (see the detailed description in the
417  .\" HREF  .\" HREF
418  \fBpcrepattern\fP  \fBpcrepattern\fP
419  .\"  .\"
420  documentation). For these options, the contents of the \fIoptions\fP argument  documentation). For those options that can be different in different parts of
421  specifies their initial settings at the start of compilation and execution. The  the pattern, the contents of the \fIoptions\fP argument specifies their initial
422  PCRE_ANCHORED and PCRE_NEWLINE_\fIxxx\fP options can be set at the time of  settings at the start of compilation and execution. The PCRE_ANCHORED and
423  matching as well as at compile time.  PCRE_NEWLINE_\fIxxx\fP options can be set at the time of matching as well as at
424    compile time.
425  .P  .P
426  If \fIerrptr\fP is NULL, \fBpcre_compile()\fP returns NULL immediately.  If \fIerrptr\fP is NULL, \fBpcre_compile()\fP returns NULL immediately.
427  Otherwise, if compilation of a pattern fails, \fBpcre_compile()\fP returns  Otherwise, if compilation of a pattern fails, \fBpcre_compile()\fP returns
# Line 549  If this option is set, an unanchored pat Line 557  If this option is set, an unanchored pat
557  the first newline in the subject string, though the matched text may continue  the first newline in the subject string, though the matched text may continue
558  over the newline.  over the newline.
559  .sp  .sp
560      PCRE_JAVASCRIPT_COMPAT
561    .sp
562    If this option is set, PCRE's behaviour is changed in some ways so that it is
563    compatible with JavaScript rather than Perl. The changes are as follows:
564    .P
565    (1) A lone closing square bracket in a pattern causes a compile-time error,
566    because this is illegal in JavaScript (by default it is treated as a data
567    character). Thus, the pattern AB]CD becomes illegal when this option is set.
568    .P
569    (2) At run time, a back reference to an unset subpattern group matches an empty
570    string (by default this causes the current matching alternative to fail). A
571    pattern such as (\e1)(a) succeeds when this option is set (assuming it can find
572    an "a" in the subject), whereas it fails by default, for Perl compatibility.
573    .sp
574    PCRE_MULTILINE    PCRE_MULTILINE
575  .sp  .sp
576  By default, PCRE treats the subject string as consisting of a single line of  By default, PCRE treats the subject string as consisting of a single line of
# Line 717  out of use. To avoid confusion, they hav Line 739  out of use. To avoid confusion, they hav
739    54  DEFINE group contains more than one branch    54  DEFINE group contains more than one branch
740    55  repeating a DEFINE group is not allowed    55  repeating a DEFINE group is not allowed
741    56  inconsistent NEWLINE options    56  inconsistent NEWLINE options
742    57  \eg is not followed by a braced name or an optionally braced    57  \eg is not followed by a braced, angle-bracketed, or quoted
743          non-zero number          name/number or by a plain number
744    58  (?+ or (?- or (?(+ or (?(- must be followed by a non-zero number    58  a numbered reference must not be zero
745    59  (*VERB) with an argument is not supported    59  (*VERB) with an argument is not supported
746    60  (*VERB) not recognized    60  (*VERB) not recognized
747    61  number is too big    61  number is too big
748    62  subpattern name expected    62  subpattern name expected
749    63  digit expected after (?+    63  digit expected after (?+
750      64  ] is an invalid data character in JavaScript compatibility mode
751  .sp  .sp
752  The numbers 32 and 10000 in errors 48 and 49 are defaults; different values may  The numbers 32 and 10000 in errors 48 and 49 are defaults; different values may
753  be used if the limits were changed when PCRE was built.  be used if the limits were changed when PCRE was built.
# Line 989  different for each compiled pattern. Line 1012  different for each compiled pattern.
1012  .sp  .sp
1013    PCRE_INFO_OKPARTIAL    PCRE_INFO_OKPARTIAL
1014  .sp  .sp
1015  Return 1 if the pattern can be used for partial matching, otherwise 0. The  Return 1 if the pattern can be used for partial matching with
1016  fourth argument should point to an \fBint\fP variable. The  \fBpcre_exec()\fP, otherwise 0. The fourth argument should point to an
1017    \fBint\fP variable. From release 8.00, this always returns 1, because the
1018    restrictions that previously applied to partial matching have been lifted. The
1019  .\" HREF  .\" HREF
1020  \fBpcrepartial\fP  \fBpcrepartial\fP
1021  .\"  .\"
1022  documentation lists the restrictions that apply to patterns when partial  documentation gives details of partial matching.
 matching is used.  
1023  .sp  .sp
1024    PCRE_INFO_OPTIONS    PCRE_INFO_OPTIONS
1025  .sp  .sp
# Line 1195  with a \fBpcre_extra\fP block in which \ Line 1219  with a \fBpcre_extra\fP block in which \
1219  PCRE_EXTRA_MATCH_LIMIT_RECURSION is set in the \fIflags\fP field. If the limit  PCRE_EXTRA_MATCH_LIMIT_RECURSION is set in the \fIflags\fP field. If the limit
1220  is exceeded, \fBpcre_exec()\fP returns PCRE_ERROR_RECURSIONLIMIT.  is exceeded, \fBpcre_exec()\fP returns PCRE_ERROR_RECURSIONLIMIT.
1221  .P  .P
1222  The \fIpcre_callout\fP field is used in conjunction with the "callout" feature,  The \fIcallout_data\fP field is used in conjunction with the "callout" feature,
1223  which is described in the  and is described in the
1224  .\" HREF  .\" HREF
1225  \fBpcrecallout\fP  \fBpcrecallout\fP
1226  .\"  .\"
# Line 1222  documentation for a discussion of saving Line 1246  documentation for a discussion of saving
1246  .sp  .sp
1247  The unused bits of the \fIoptions\fP argument for \fBpcre_exec()\fP must be  The unused bits of the \fIoptions\fP argument for \fBpcre_exec()\fP must be
1248  zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP,  zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP,
1249  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_UTF8_CHECK and PCRE_PARTIAL.  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_START_OPTIMIZE,
1250    PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_SOFT, and PCRE_PARTIAL_HARD.
1251  .sp  .sp
1252    PCRE_ANCHORED    PCRE_ANCHORED
1253  .sp  .sp
# Line 1307  when using the /g modifier. It is possib Line 1332  when using the /g modifier. It is possib
1332  matching a null string by first trying the match again at the same offset with  matching a null string by first trying the match again at the same offset with
1333  PCRE_NOTEMPTY and PCRE_ANCHORED, and then if that fails by advancing the  PCRE_NOTEMPTY and PCRE_ANCHORED, and then if that fails by advancing the
1334  starting offset (see below) and trying an ordinary match again. There is some  starting offset (see below) and trying an ordinary match again. There is some
1335  code that demonstrates how to do this in the \fIpcredemo.c\fP sample program.  code that demonstrates how to do this in the
1336    .\" HREF
1337    \fBpcredemo\fP
1338    .\"
1339    sample program.
1340    .sp
1341      PCRE_NO_START_OPTIMIZE
1342    .sp
1343    There are a number of optimizations that \fBpcre_exec()\fP uses at the start of
1344    a match, in order to speed up the process. For example, if it is known that a
1345    match must start with a specific character, it searches the subject for that
1346    character, and fails immediately if it cannot find it, without actually running
1347    the main matching function. When callouts are in use, these optimizations can
1348    cause them to be skipped. This option disables the "start-up" optimizations,
1349    causing performance to suffer, but ensuring that the callouts do occur.
1350  .sp  .sp
1351    PCRE_NO_UTF8_CHECK    PCRE_NO_UTF8_CHECK
1352  .sp  .sp
# Line 1338  PCRE_NO_UTF8_CHECK is set, the effect of Line 1377  PCRE_NO_UTF8_CHECK is set, the effect of
1377  subject, or a value of \fIstartoffset\fP that does not point to the start of a  subject, or a value of \fIstartoffset\fP that does not point to the start of a
1378  UTF-8 character, is undefined. Your program may crash.  UTF-8 character, is undefined. Your program may crash.
1379  .sp  .sp
1380    PCRE_PARTIAL    PCRE_PARTIAL_HARD
1381      PCRE_PARTIAL_SOFT
1382  .sp  .sp
1383  This option turns on the partial matching feature. If the subject string fails  These options turn on the partial matching feature. For backwards
1384  to match the pattern, but at some point during the matching process the end of  compatibility, PCRE_PARTIAL is a synonym for PCRE_PARTIAL_SOFT. A partial match
1385  the subject was reached (that is, the subject partially matches the pattern and  occurs if the end of the subject string is reached successfully, but there are
1386  the failure to match occurred only because there were not enough subject  not enough subject characters to complete the match. If this happens when
1387  characters), \fBpcre_exec()\fP returns PCRE_ERROR_PARTIAL instead of  PCRE_PARTIAL_HARD is set, \fBpcre_exec()\fP immediately returns
1388  PCRE_ERROR_NOMATCH. When PCRE_PARTIAL is used, there are restrictions on what  PCRE_ERROR_PARTIAL. Otherwise, if PCRE_PARTIAL_SOFT is set, matching continues
1389  may appear in the pattern. These are discussed in the  by testing any other alternatives. Only if they all fail is PCRE_ERROR_PARTIAL
1390    returned (instead of PCRE_ERROR_NOMATCH). The portion of the string that
1391    was inspected when the partial match was found is set as the first matching
1392    string. There is a more detailed discussion in the
1393  .\" HREF  .\" HREF
1394  \fBpcrepartial\fP  \fBpcrepartial\fP
1395  .\"  .\"
# Line 1356  documentation. Line 1399  documentation.
1399  .rs  .rs
1400  .sp  .sp
1401  The subject string is passed to \fBpcre_exec()\fP as a pointer in  The subject string is passed to \fBpcre_exec()\fP as a pointer in
1402  \fIsubject\fP, a length in \fIlength\fP, and a starting byte offset in  \fIsubject\fP, a length (in bytes) in \fIlength\fP, and a starting byte offset
1403  \fIstartoffset\fP. In UTF-8 mode, the byte offset must point to the start of a  in \fIstartoffset\fP. In UTF-8 mode, the byte offset must point to the start of
1404  UTF-8 character. Unlike the pattern string, the subject may contain binary zero  a UTF-8 character. Unlike the pattern string, the subject may contain binary
1405  bytes. When the starting offset is zero, the search for a match starts at the  zero bytes. When the starting offset is zero, the search for a match starts at
1406  beginning of the subject, and this is by far the most common case.  the beginning of the subject, and this is by far the most common case.
1407  .P  .P
1408  A non-zero starting offset is useful when searching for another match in the  A non-zero starting offset is useful when searching for another match in the
1409  same subject by calling \fBpcre_exec()\fP again after a previous success.  same subject by calling \fBpcre_exec()\fP again after a previous success.
# Line 1394  pattern. Following the usage in Jeffrey Line 1437  pattern. Following the usage in Jeffrey
1437  a fragment of a pattern that picks out a substring. PCRE supports several other  a fragment of a pattern that picks out a substring. PCRE supports several other
1438  kinds of parenthesized subpattern that do not cause substrings to be captured.  kinds of parenthesized subpattern that do not cause substrings to be captured.
1439  .P  .P
1440  Captured substrings are returned to the caller via a vector of integer offsets  Captured substrings are returned to the caller via a vector of integers whose
1441  whose address is passed in \fIovector\fP. The number of elements in the vector  address is passed in \fIovector\fP. The number of elements in the vector is
1442  is passed in \fIovecsize\fP, which must be a non-negative number. \fBNote\fP:  passed in \fIovecsize\fP, which must be a non-negative number. \fBNote\fP: this
1443  this argument is NOT the size of \fIovector\fP in bytes.  argument is NOT the size of \fIovector\fP in bytes.
1444  .P  .P
1445  The first two-thirds of the vector is used to pass back captured substrings,  The first two-thirds of the vector is used to pass back captured substrings,
1446  each substring using a pair of integers. The remaining third of the vector is  each substring using a pair of integers. The remaining third of the vector is
1447  used as workspace by \fBpcre_exec()\fP while matching capturing subpatterns,  used as workspace by \fBpcre_exec()\fP while matching capturing subpatterns,
1448  and is not available for passing back information. The length passed in  and is not available for passing back information. The number passed in
1449  \fIovecsize\fP should always be a multiple of three. If it is not, it is  \fIovecsize\fP should always be a multiple of three. If it is not, it is
1450  rounded down.  rounded down.
1451  .P  .P
1452  When a match is successful, information about captured substrings is returned  When a match is successful, information about captured substrings is returned
1453  in pairs of integers, starting at the beginning of \fIovector\fP, and  in pairs of integers, starting at the beginning of \fIovector\fP, and
1454  continuing up to two-thirds of its length at the most. The first element of a  continuing up to two-thirds of its length at the most. The first element of
1455  pair is set to the offset of the first character in a substring, and the second  each pair is set to the byte offset of the first character in a substring, and
1456  is set to the offset of the first character after the end of a substring. The  the second is set to the byte offset of the first character after the end of a
1457  first pair, \fIovector[0]\fP and \fIovector[1]\fP, identify the portion of the  substring. \fBNote\fP: these values are always byte offsets, even in UTF-8
1458  subject string matched by the entire pattern. The next pair is used for the  mode. They are not character counts.
1459  first capturing subpattern, and so on. The value returned by \fBpcre_exec()\fP  .P
1460  is one more than the highest numbered pair that has been set. For example, if  The first pair of integers, \fIovector[0]\fP and \fIovector[1]\fP, identify the
1461  two substrings have been captured, the returned value is 3. If there are no  portion of the subject string matched by the entire pattern. The next pair is
1462  capturing subpatterns, the return value from a successful match is 1,  used for the first capturing subpattern, and so on. The value returned by
1463  indicating that just the first pair of offsets has been set.  \fBpcre_exec()\fP is one more than the highest numbered pair that has been set.
1464    For example, if two substrings have been captured, the returned value is 3. If
1465    there are no capturing subpatterns, the return value from a successful match is
1466    1, indicating that just the first pair of offsets has been set.
1467  .P  .P
1468  If a capturing subpattern is matched repeatedly, it is the last portion of the  If a capturing subpattern is matched repeatedly, it is the last portion of the
1469  string that it matched that is returned.  string that it matched that is returned.
1470  .P  .P
1471  If the vector is too small to hold all the captured substring offsets, it is  If the vector is too small to hold all the captured substring offsets, it is
1472  used as far as possible (up to two-thirds of its length), and the function  used as far as possible (up to two-thirds of its length), and the function
1473  returns a value of zero. In particular, if the substring offsets are not of  returns a value of zero. If the substring offsets are not of interest,
1474  interest, \fBpcre_exec()\fP may be called with \fIovector\fP passed as NULL and  \fBpcre_exec()\fP may be called with \fIovector\fP passed as NULL and
1475  \fIovecsize\fP as zero. However, if the pattern contains back references and  \fIovecsize\fP as zero. However, if the pattern contains back references and
1476  the \fIovector\fP is not big enough to remember the related substrings, PCRE  the \fIovector\fP is not big enough to remember the related substrings, PCRE
1477  has to get additional memory for use during matching. Thus it is usually  has to get additional memory for use during matching. Thus it is usually
# Line 1536  documentation for details of partial mat Line 1582  documentation for details of partial mat
1582  .sp  .sp
1583    PCRE_ERROR_BADPARTIAL     (-13)    PCRE_ERROR_BADPARTIAL     (-13)
1584  .sp  .sp
1585  The PCRE_PARTIAL option was used with a compiled pattern containing items that  This code is no longer in use. It was formerly returned when the PCRE_PARTIAL
1586  are not supported for partial matching. See the  option was used with a compiled pattern containing items that were not
1587  .\" HREF  supported for partial matching. From release 8.00 onwards, there are no
1588  \fBpcrepartial\fP  restrictions on partial matching.
 .\"  
 documentation for details of partial matching.  
1589  .sp  .sp
1590    PCRE_ERROR_INTERNAL       (-14)    PCRE_ERROR_INTERNAL       (-14)
1591  .sp  .sp
# Line 1711  These functions call \fBpcre_get_stringn Line 1755  These functions call \fBpcre_get_stringn
1755  then call \fBpcre_copy_substring()\fP or \fBpcre_get_substring()\fP, as  then call \fBpcre_copy_substring()\fP or \fBpcre_get_substring()\fP, as
1756  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,
1757  the behaviour may not be what you want (see the next section).  the behaviour may not be what you want (see the next section).
1758  .  .P
1759    \fBWarning:\fP If the pattern uses the "(?|" feature to set up multiple
1760    subpatterns with the same number, you cannot use names to distinguish them,
1761    because names are not included in the compiled code. The matching process uses
1762    only numbers.
1763  .  .
1764  .SH "DUPLICATE SUBPATTERN NAMES"  .SH "DUPLICATE SUBPATTERN NAMES"
1765  .rs  .rs
# Line 1787  a compiled pattern, using a matching alg Line 1835  a compiled pattern, using a matching alg
1835  just once, and does not backtrack. This has different characteristics to the  just once, and does not backtrack. This has different characteristics to the
1836  normal algorithm, and is not compatible with Perl. Some of the features of PCRE  normal algorithm, and is not compatible with Perl. Some of the features of PCRE
1837  patterns are not supported. Nevertheless, there are times when this kind of  patterns are not supported. Nevertheless, there are times when this kind of
1838  matching can be useful. For a discussion of the two matching algorithms, see  matching can be useful. For a discussion of the two matching algorithms, and a
1839  the  list of features that \fBpcre_dfa_exec()\fP does not support, see the
1840  .\" HREF  .\" HREF
1841  \fBpcrematching\fP  \fBpcrematching\fP
1842  .\"  .\"
# Line 1827  Here is an example of a simple call to \ Line 1875  Here is an example of a simple call to \
1875  .sp  .sp
1876  The unused bits of the \fIoptions\fP argument for \fBpcre_dfa_exec()\fP must be  The unused bits of the \fIoptions\fP argument for \fBpcre_dfa_exec()\fP must be
1877  zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP,  zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP,
1878  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL,  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_HARD,
1879  PCRE_DFA_SHORTEST, and PCRE_DFA_RESTART. All but the last three of these are  PCRE_PARTIAL_SOFT, PCRE_DFA_SHORTEST, and PCRE_DFA_RESTART. All but the last
1880  the same as for \fBpcre_exec()\fP, so their description is not repeated here.  four of these are exactly the same as for \fBpcre_exec()\fP, so their
1881  .sp  description is not repeated here.
1882    PCRE_PARTIAL  .sp
1883  .sp    PCRE_PARTIAL_HARD
1884  This has the same general effect as it does for \fBpcre_exec()\fP, but the    PCRE_PARTIAL_SOFT
1885  details are slightly different. When PCRE_PARTIAL is set for  .sp
1886  \fBpcre_dfa_exec()\fP, the return code PCRE_ERROR_NOMATCH is converted into  These have the same general effect as they do for \fBpcre_exec()\fP, but the
1887  PCRE_ERROR_PARTIAL if the end of the subject is reached, there have been no  details are slightly different. When PCRE_PARTIAL_HARD is set for
1888  complete matches, but there is still at least one matching possibility. The  \fBpcre_dfa_exec()\fP, it returns PCRE_ERROR_PARTIAL if the end of the subject
1889  portion of the string that provided the partial match is set as the first  is reached and there is still at least one matching possibility that requires
1890  matching string.  additional characters. This happens even if some complete matches have also
1891    been found. When PCRE_PARTIAL_SOFT is set, the return code PCRE_ERROR_NOMATCH
1892    is converted into PCRE_ERROR_PARTIAL if the end of the subject is reached,
1893    there have been no complete matches, but there is still at least one matching
1894    possibility. The portion of the string that was inspected when the longest
1895    partial match was found is set as the first matching string in both cases.
1896  .sp  .sp
1897    PCRE_DFA_SHORTEST    PCRE_DFA_SHORTEST
1898  .sp  .sp
# Line 1850  matching point in the subject string. Line 1903  matching point in the subject string.
1903  .sp  .sp
1904    PCRE_DFA_RESTART    PCRE_DFA_RESTART
1905  .sp  .sp
1906  When \fBpcre_dfa_exec()\fP is called with the PCRE_PARTIAL option, and returns  When \fBpcre_dfa_exec()\fP returns a partial match, it is possible to call it
1907  a partial match, it is possible to call it again, with additional subject  again, with additional subject characters, and have it continue with the same
1908  characters, and have it continue with the same match. The PCRE_DFA_RESTART  match. The PCRE_DFA_RESTART option requests this action; when it is set, the
1909  option requests this action; when it is set, the \fIworkspace\fP and  \fIworkspace\fP and \fIwscount\fP options must reference the same vector as
1910  \fIwscount\fP options must reference the same vector as before because data  before because data about the match so far is left in them after a partial
1911  about the match so far is left in them after a partial match. There is more  match. There is more discussion of this facility in the
 discussion of this facility in the  
1912  .\" HREF  .\" HREF
1913  \fBpcrepartial\fP  \fBpcrepartial\fP
1914  .\"  .\"
# Line 1960  Cambridge CB2 3QH, England. Line 2012  Cambridge CB2 3QH, England.
2012  .rs  .rs
2013  .sp  .sp
2014  .nf  .nf
2015  Last updated: 26 December 2007  Last updated: 09 September 2009
2016  Copyright (c) 1997-2007 University of Cambridge.  Copyright (c) 1997-2009 University of Cambridge.
2017  .fi  .fi

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