/[pcre]/code/trunk/doc/pcreapi.3

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-revision 642 by ph10,
Thu Jul 28 18:59:40 2011 UTC
+revision 745 by ph10,
Mon Nov 14 11:41:03 2011 UTC
 Line 1
  .TH PCREAPI 3
  .SH NAME
  PCRE - Perl-compatible regular expressions
- .SH "PCRE NATIVE API"
+ .SH "PCRE NATIVE API BASIC FUNCTIONS"
  .rs
  .sp
  .B #include <pcre.h>
 Line 25 
 PCRE - Perl-compatible regular expressio
  .ti +5n
  .B const char **\fIerrptr\fP);
  .PP
+ .B void pcre_free_study(pcre_extra *\fIextra\fP);
+ .PP
  .B int pcre_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
  .ti +5n
  .B "const char *\fIsubject\fP," int \fIlength\fP, int \fIstartoffset\fP,
  .ti +5n
  .B int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);
+ .
+ .
+ .SH "PCRE NATIVE API AUXILIARY FUNCTIONS"
+ .rs
+ .sp
+ .B pcre_jit_stack *pcre_jit_stack_alloc(int \fIstartsize\fP, int \fImaxsize\fP);
+ .PP
+ .B void pcre_jit_stack_free(pcre_jit_stack *\fIstack\fP);
+ .PP
+ .B void pcre_assign_jit_stack(pcre_extra *\fIextra\fP,
+ .ti +5n
+ .B pcre_jit_callback \fIcallback\fP, void *\fIdata\fP);
  .PP
  .B int pcre_dfa_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
  .ti +5n
-Line 97 
 PCRE - Perl-compatible regular expressio
+Line 111 
 PCRE - Perl-compatible regular expressio
  .B int pcre_config(int \fIwhat\fP, void *\fIwhere\fP);
  .PP
  .B char *pcre_version(void);
- .PP
+ .
+ .
+ .SH "PCRE NATIVE API INDIRECTED FUNCTIONS"
+ .rs
+ .sp
  .B void *(*pcre_malloc)(size_t);
  .PP
  .B void (*pcre_free)(void *);
-Line 114 
 PCRE - Perl-compatible regular expressio
+Line 132 
 PCRE - Perl-compatible regular expressio
  .sp
  PCRE has its own native API, which is described in this document. There are
  also some wrapper functions that correspond to the POSIX regular expression
- API. These are described in the
+ API, but they do not give access to all the functionality. They are described
+ in the
  .\" HREF
  \fBpcreposix\fP
  .\"
  documentation. Both of these APIs define a set of C function calls. A C++
- wrapper is distributed with PCRE. It is documented in the
+ wrapper is also distributed with PCRE. It is documented in the
  .\" HREF
  \fBpcrecpp\fP
  .\"
-Line 152 
 documentation, and the
+Line 171 
 documentation, and the
  .\"
  documentation describes how to compile and run it.
  .P
+ Just-in-time compiler support is an optional feature of PCRE that can be built
+ in appropriate hardware environments. It greatly speeds up the matching
+ performance of many patterns. Simple programs can easily request that it be
+ used if available, by setting an option that is ignored when it is not
+ relevant. More complicated programs might need to make use of the functions
+ \fBpcre_jit_stack_alloc()\fP, \fBpcre_jit_stack_free()\fP, and
+ \fBpcre_assign_jit_stack()\fP in order to control the JIT code's memory usage.
+ These functions are discussed in the
+ .\" HREF
+ \fBpcrejit\fP
+ .\"
+ documentation.
+ .P
  A second matching function, \fBpcre_dfa_exec()\fP, which is not
  Perl-compatible, is also provided. This uses a different algorithm for the
  matching. The alternative algorithm finds all possible matches (at a given
-Line 282 
 callout function pointed to by \fBpcre_c
+Line 314 
 callout function pointed to by \fBpcre_c
  .P
  The compiled form of a regular expression is not altered during matching, so
  the same compiled pattern can safely be used by several threads at once.
+ .P
+ If the just-in-time optimization feature is being used, it needs separate
+ memory stack areas for each thread. See the
+ .\" HREF
+ \fBpcrejit\fP
+ .\"
+ documentation for more details.
  .
  .
  .SH "SAVING PRECOMPILED PATTERNS FOR LATER USE"
-Line 324 
 otherwise it is set to zero.
+Line 363 
 otherwise it is set to zero.
  The output is an integer that is set to one if support for Unicode character
  properties is available; otherwise it is set to zero.
  .sp
+   PCRE_CONFIG_JIT
+ .sp
+ The output is an integer that is set to one if support for just-in-time
+ compiling is available; otherwise it is set to zero.
+ .sp
    PCRE_CONFIG_NEWLINE
  .sp
  The output is an integer whose value specifies the default character sequence
-Line 599 
 character). Thus, the pattern AB]CD beco
+Line 643 
 character). Thus, the pattern AB]CD beco
  string (by default this causes the current matching alternative to fail). A
  pattern such as (\e1)(a) succeeds when this option is set (assuming it can find
  an "a" in the subject), whereas it fails by default, for Perl compatibility.
+ .P
+ (3) \eU matches an upper case "U" character; by default \eU causes a compile
+ time error (Perl uses \eU to upper case subsequent characters).
+ .P
+ (4) \eu matches a lower case "u" character unless it is followed by four
+ hexadecimal digits, in which case the hexadecimal number defines the code point
+ to match. By default, \eu causes a compile time error (Perl uses it to upper
+ case the following character).
+ .P
+ (5) \ex matches a lower case "x" character unless it is followed by two
+ hexadecimal digits, in which case the hexadecimal number defines the code point
+ to match. By default, as in Perl, a hexadecimal number is always expected after
+ \ex, but it may have zero, one, or two digits (so, for example, \exz matches a
+ binary zero character followed by z).
  .sp
    PCRE_MULTILINE
  .sp
-Line 701 
 of UTF-8 characters instead of single-by
+Line 759 
 of UTF-8 characters instead of single-by
  available only when PCRE is built to include UTF-8 support. If not, the use
  of this option provokes an error. Details of how this option changes the
  behaviour of PCRE are given in the
- .\" HTML <a href="pcre.html#utf8support">
- .\" </a>
- section on UTF-8 support
- .\"
- in the main
  .\" HREF
- \fBpcre\fP
+ \fBpcreunicode\fP
  .\"
  page.
  .sp
-Line 777 
 out of use. To avoid confusion, they hav
+Line 830 
 out of use. To avoid confusion, they hav
  character value in \ex{...} sequence is too large
  invalid condition (?(0)
  \eC not allowed in lookbehind assertion
- PCRE does not support \eL, \el, \eN, \eU, or \eu
+ PCRE does not support \eL, \el, \eN{name}, \eU, or \eu
  number after (?C is > 255
  closing ) for (?C expected
  recursive call could loop indefinitely
-Line 811 
 out of use. To avoid confusion, they hav
+Line 864 
 out of use. To avoid confusion, they hav
          not allowed
  (*MARK) must have an argument
  this version of PCRE is not compiled with PCRE_UCP support
+ \ec must be followed by an ASCII character
+ \ek is not followed by a braced, angle-bracketed, or quoted name
  .sp
  The numbers 32 and 10000 in errors 48 and 49 are defaults; different values may
  be used if the limits were changed when PCRE was built.
  .
  .
+ .\" HTML <a name="studyingapattern"></a>
  .SH "STUDYING A PATTERN"
  .rs
  .sp
-Line 846 
 If studying the pattern does not produce
+Line 902 
 If studying the pattern does not produce
  wants to pass any of the other fields to \fBpcre_exec()\fP or
  \fBpcre_dfa_exec()\fP, it must set up its own \fBpcre_extra\fP block.
  .P
- The second argument of \fBpcre_study()\fP contains option bits. At present, no
+ The second argument of \fBpcre_study()\fP contains option bits. There is only
- options are defined, and this argument should always be zero.
+ one option: PCRE_STUDY_JIT_COMPILE. If this is set, and the just-in-time
+ compiler is available, the pattern is further compiled into machine code that
+ executes much faster than the \fBpcre_exec()\fP matching function. If
+ the just-in-time compiler is not available, this option is ignored. All other
+ bits in the \fIoptions\fP argument must be zero.
+ .P
+ JIT compilation is a heavyweight optimization. It can take some time for
+ patterns to be analyzed, and for one-off matches and simple patterns the
+ benefit of faster execution might be offset by a much slower study time.
+ Not all patterns can be optimized by the JIT compiler. For those that cannot be
+ handled, matching automatically falls back to the \fBpcre_exec()\fP
+ interpreter. For more details, see the
+ .\" HREF
+ \fBpcrejit\fP
+ .\"
+ documentation.
  .P
  The third argument for \fBpcre_study()\fP is a pointer for an error message. If
  studying succeeds (even if no data is returned), the variable it points to is
-Line 856 
 static string that is part of the librar
+Line 927 
 static string that is part of the librar
  should test the error pointer for NULL after calling \fBpcre_study()\fP, to be
  sure that it has run successfully.
  .P
- This is a typical call to \fBpcre_study\fP():
+ When you are finished with a pattern, you can free the memory used for the
+ study data by calling \fBpcre_free_study()\fP. This function was added to the
+ API for release 8.20. For earlier versions, the memory could be freed with
+ \fBpcre_free()\fP, just like the pattern itself. This will still work in cases
+ where PCRE_STUDY_JIT_COMPILE is not used, but it is advisable to change to the
+ new function when convenient.
+ .P
+ This is a typical way in which \fBpcre_study\fP() is used (except that in a
+ real application there should be tests for errors):
  .sp
-   pcre_extra *pe;
+   int rc;
-   pe = pcre_study(
+   pcre *re;
+   pcre_extra *sd;
+   re = pcre_compile("pattern", 0, &error, &erroroffset, NULL);
+   sd = pcre_study(
      re,             /* result of pcre_compile() */
-,              /* no options exist */
+,              /* no options */
      &error);        /* set to NULL or points to a message */
+   rc = pcre_exec(   /* see below for details of pcre_exec() options */
+     re, sd, "subject", 7, 0, 0, ovector, 30);
+   ...
+   pcre_free_study(sd);
+   pcre_free(re);
  .sp
  Studying a pattern does two things: first, a lower bound for the length of
  subject string that is needed to match the pattern is computed. This does not
-Line 877 
 single fixed starting character. A bitma
+Line 964 
 single fixed starting character. A bitma
  created. This speeds up finding a position in the subject at which to start
  matching.
  .P
- The two optimizations just described can be disabled by setting the
+ These two optimizations apply to both \fBpcre_exec()\fP and
- PCRE_NO_START_OPTIMIZE option when calling \fBpcre_exec()\fP or
+ \fBpcre_dfa_exec()\fP. However, they are not used by \fBpcre_exec()\fP if
+ \fBpcre_study()\fP is called with the PCRE_STUDY_JIT_COMPILE option, and
+ just-in-time compiling is successful. The optimizations can be disabled by
+ setting the PCRE_NO_START_OPTIMIZE option when calling \fBpcre_exec()\fP or
  \fBpcre_dfa_exec()\fP. You might want to do this if your pattern contains
- callouts or (*MARK), and you want to make use of these facilities in cases
+ callouts or (*MARK) (which cannot be handled by the JIT compiler), and you want
- where matching fails. See the discussion of PCRE_NO_START_OPTIMIZE
+ to make use of these facilities in cases where matching fails. See the
+ discussion of PCRE_NO_START_OPTIMIZE
  .\" HTML <a href="#execoptions">
  .\" </a>
  below.
-Line 978 
 check against passing an arbitrary memor
+Line 1069 
 check against passing an arbitrary memor
    size_t length;
    rc = pcre_fullinfo(
      re,               /* result of pcre_compile() */
-     pe,               /* result of pcre_study(), or NULL */
+     sd,               /* result of pcre_study(), or NULL */
      PCRE_INFO_SIZE,   /* what is required */
      &length);         /* where to put the data */
  .sp
-Line 1043 
 Return 1 if the (?J) or (?-J) option set
+Line 1134 
 Return 1 if the (?J) or (?-J) option set
 . The fourth argument should point to an \fBint\fP variable. (?J) and
  (?-J) set and unset the local PCRE_DUPNAMES option, respectively.
  .sp
+   PCRE_INFO_JIT
+ .sp
+ Return 1 if the pattern was studied with the PCRE_STUDY_JIT_COMPILE option, and
+ just-in-time compiling was successful. The fourth argument should point to an
+ \fBint\fP variable. A return value of 0 means that JIT support is not available
+ in this version of PCRE, or that the pattern was not studied with the
+ PCRE_STUDY_JIT_COMPILE option, or that the JIT compiler could not handle this
+ particular pattern. See the
+ .\" HREF
+ \fBpcrejit\fP
+ .\"
+ documentation for details of what can and cannot be handled.
+ .sp
    PCRE_INFO_LASTLITERAL
  .sp
  Return the value of the rightmost literal byte that must exist in any matched
-Line 1165 
 variable.
+Line 1269 
 variable.
  .sp
    PCRE_INFO_STUDYSIZE
  .sp
- Return the size of the data block pointed to by the \fIstudy_data\fP field in
+ Return the size of the data block pointed to by the \fIstudy_data\fP field in a
- a \fBpcre_extra\fP block. That is, it is the value that was passed to
+ \fBpcre_extra\fP block. If \fBpcre_extra\fP is NULL, or there is no study data,
- \fBpcre_malloc()\fP when PCRE was getting memory into which to place the data
+ zero is returned. The fourth argument should point to a \fBsize_t\fP variable.
- created by \fBpcre_study()\fP. If \fBpcre_extra\fP is NULL, or there is no
+ The \fIstudy_data\fP field is set by \fBpcre_study()\fP to record information
- study data, zero is returned. The fourth argument should point to a
+ that will speed up matching (see the section entitled
- \fBsize_t\fP variable.
+ .\" HTML <a href="#studyingapattern">
+ .\" </a>
+ "Studying a pattern"
+ .\"
+ above). The format of the \fIstudy_data\fP block is private, but its length
+ is made available via this option so that it can be saved and restored (see the
+ .\" HREF
+ \fBpcreprecompile\fP
+ .\"
+ documentation for details).
  .
  .
  .SH "OBSOLETE INFO FUNCTION"
-Line 1232 
 is different. (This seems a highly unlik
+Line 1345 
 is different. (This seems a highly unlik
  The function \fBpcre_exec()\fP is called to match a subject string against a
  compiled pattern, which is passed in the \fIcode\fP argument. If the
  pattern was studied, the result of the study should be passed in the
- \fIextra\fP argument. This function is the main matching facility of the
+ \fIextra\fP argument. You can call \fBpcre_exec()\fP with the same \fIcode\fP
- library, and it operates in a Perl-like manner. For specialist use there is
+ and \fIextra\fP arguments as many times as you like, in order to match
- also an alternative matching function, which is described
+ different subject strings with the same pattern.
+ .P
+ This function is the main matching facility of the library, and it operates in
+ a Perl-like manner. For specialist use there is also an alternative matching
+ function, which is described
  .\" HTML <a href="#dfamatch">
  .\" </a>
  below
-Line 1265 
 Here is an example of a simple call to \
+Line 1382 
 Here is an example of a simple call to \
      ovector,        /* vector of integers for substring information */
 );            /* number of elements (NOT size in bytes) */
  .
+ .
  .\" HTML <a name="extradata"></a>
  .SS "Extra data for \fBpcre_exec()\fR"
  .rs
-Line 1277 
 fields (not necessarily in this order):
+Line 1395 
 fields (not necessarily in this order):
  .sp
    unsigned long int \fIflags\fP;
    void *\fIstudy_data\fP;
+   void *\fIexecutable_jit\fP;
    unsigned long int \fImatch_limit\fP;
    unsigned long int \fImatch_limit_recursion\fP;
    void *\fIcallout_data\fP;
-Line 1287 
 The \fIflags\fP field is a bitmap that s
+Line 1406 
 The \fIflags\fP field is a bitmap that s
  are set. The flag bits are:
  .sp
    PCRE_EXTRA_STUDY_DATA
+   PCRE_EXTRA_EXECUTABLE_JIT
    PCRE_EXTRA_MATCH_LIMIT
    PCRE_EXTRA_MATCH_LIMIT_RECURSION
    PCRE_EXTRA_CALLOUT_DATA
    PCRE_EXTRA_TABLES
    PCRE_EXTRA_MARK
  .sp
- Other flag bits should be set to zero. The \fIstudy_data\fP field is set in the
+ Other flag bits should be set to zero. The \fIstudy_data\fP field and sometimes
- \fBpcre_extra\fP block that is returned by \fBpcre_study()\fP, together with
+ the \fIexecutable_jit\fP field are set in the \fBpcre_extra\fP block that is
- the appropriate flag bit. You should not set this yourself, but you may add to
+ returned by \fBpcre_study()\fP, together with the appropriate flag bits. You
- the block by setting the other fields and their corresponding flag bits.
+ should not set these yourself, but you may add to the block by setting the
+ other fields and their corresponding flag bits.
  .P
  The \fImatch_limit\fP field provides a means of preventing PCRE from using up a
  vast amount of resources when running patterns that are not going to match,
  but which have a very large number of possibilities in their search trees. The
  classic example is a pattern that uses nested unlimited repeats.
  .P
- Internally, PCRE uses a function called \fBmatch()\fP which it calls repeatedly
+ Internally, \fBpcre_exec()\fP uses a function called \fBmatch()\fP, which it
- (sometimes recursively). The limit set by \fImatch_limit\fP is imposed on the
+ calls repeatedly (sometimes recursively). The limit set by \fImatch_limit\fP is
- number of times this function is called during a match, which has the effect of
+ imposed on the number of times this function is called during a match, which
- limiting the amount of backtracking that can take place. For patterns that are
+ has the effect of limiting the amount of backtracking that can take place. For
- not anchored, the count restarts from zero for each position in the subject
+ patterns that are not anchored, the count restarts from zero for each position
- string.
+ in the subject string.
+ .P
+ When \fBpcre_exec()\fP is called with a pattern that was successfully studied
+ with the PCRE_STUDY_JIT_COMPILE option, the way that the matching is executed
+ is entirely different. However, there is still the possibility of runaway
+ matching that goes on for a very long time, and so the \fImatch_limit\fP value
+ is also used in this case (but in a different way) to limit how long the
+ matching can continue.
  .P
  The default value for the limit can be set when PCRE is built; the default
  default is 10 million, which handles all but the most extreme cases. You can
-Line 1323 
 limits the depth of recursion. The recur
+Line 1451 
 limits the depth of recursion. The recur
  total number of calls, because not all calls to \fBmatch()\fP are recursive.
  This limit is of use only if it is set smaller than \fImatch_limit\fP.
  .P
- Limiting the recursion depth limits the amount of stack that can be used, or,
+ Limiting the recursion depth limits the amount of machine stack that can be
- when PCRE has been compiled to use memory on the heap instead of the stack, the
+ used, or, when PCRE has been compiled to use memory on the heap instead of the
- amount of heap memory that can be used.
+ stack, the amount of heap memory that can be used. This limit is not relevant,
+ and is ignored, if the pattern was successfully studied with
+ PCRE_STUDY_JIT_COMPILE.
  .P
  The default value for \fImatch_limit_recursion\fP can be set when PCRE is
  built; the default default is the same value as the default for
-Line 1384 
 zero. The only bits that may be set are
+Line 1514 
 zero. The only bits that may be set are
  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,
  PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_SOFT, and
  PCRE_PARTIAL_HARD.
+ .P
+ If the pattern was successfully studied with the PCRE_STUDY_JIT_COMPILE option,
+ the only supported options for JIT execution are PCRE_NO_UTF8_CHECK,
+ PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, and PCRE_NOTEMPTY_ATSTART. Note in
+ particular that partial matching is not supported. If an unsupported option is
+ used, JIT execution is disabled and the normal interpretive code in
+ \fBpcre_exec()\fP is run.
  .sp
    PCRE_ANCHORED
  .sp
-Line 1548 
 in the main
+Line 1685 
 in the main
  .\"
  page. If an invalid UTF-8 sequence of bytes is found, \fBpcre_exec()\fP returns
  the error PCRE_ERROR_BADUTF8 or, if PCRE_PARTIAL_HARD is set and the problem is
  a truncated UTF-8 character at the end of the subject, PCRE_ERROR_SHORTUTF8. In
  both cases, information about the precise nature of the error may also be
  returned (see the descriptions of these errors in the section entitled \fIError
  return values from\fP \fBpcre_exec()\fP
-Line 1690 
 string that it matched that is returned.
+Line 1827 
 string that it matched that is returned.
  .P
  If the vector is too small to hold all the captured substring offsets, it is
  used as far as possible (up to two-thirds of its length), and the function
- returns a value of zero. If the substring offsets are not of interest,
+ returns a value of zero. If neither the actual string matched not any captured
- \fBpcre_exec()\fP may be called with \fIovector\fP passed as NULL and
+ substrings are of interest, \fBpcre_exec()\fP may be called with \fIovector\fP
- \fIovecsize\fP as zero. However, if the pattern contains back references and
+ passed as NULL and \fIovecsize\fP as zero. However, if the pattern contains
- the \fIovector\fP is not big enough to remember the related substrings, PCRE
+ back references and the \fIovector\fP is not big enough to remember the related
- has to get additional memory for use during matching. Thus it is usually
+ substrings, PCRE has to get additional memory for use during matching. Thus it
- advisable to supply an \fIovector\fP.
+ is usually advisable to supply an \fIovector\fP of reasonable size.
+ .P
+ There are some cases where zero is returned (indicating vector overflow) when
+ in fact the vector is exactly the right size for the final match. For example,
+ consider the pattern
+ .sp
+   (a)(?:(b)c|bd)
+ .sp
+ If a vector of 6 elements (allowing for only 1 captured substring) is given
+ with subject string "abd", \fBpcre_exec()\fP will try to set the second
+ captured string, thereby recording a vector overflow, before failing to match
+ "c" and backing up to try the second alternative. The zero return, however,
+ does correctly indicate that the maximum number of slots (namely 2) have been
+ filled. In similar cases where there is temporary overflow, but the final
+ number of used slots is actually less than the maximum, a non-zero value is
+ returned.
  .P
  The \fBpcre_fullinfo()\fP function can be used to find out how many capturing
  subpatterns there are in a compiled pattern. The smallest size for
-Line 1716 
 return from the function is 2, because t
+Line 1868 
 return from the function is 2, because t
  number is 1, and the offsets for for the second and third capturing subpatterns
  (assuming the vector is large enough, of course) are set to -1.
  .P
- \fBNote\fP: Elements of \fIovector\fP that do not correspond to capturing
+ \fBNote\fP: Elements in the first two-thirds of \fIovector\fP that do not
- parentheses in the pattern are never changed. That is, if a pattern contains
+ correspond to capturing parentheses in the pattern are never changed. That is,
- \fIn\fP capturing parentheses, no more than \fIovector[0]\fP to
+ if a pattern contains \fIn\fP capturing parentheses, no more than
- \fIovector[2n+1]\fP are set by \fBpcre_exec()\fP. The other elements retain
+ \fIovector[0]\fP to \fIovector[2n+1]\fP are set by \fBpcre_exec()\fP. The other
- whatever values they previously had.
+ elements (in the first two-thirds) retain whatever values they previously had.
  .P
  Some convenience functions are provided for extracting the captured substrings
  as separate strings. These are described below.
-Line 1810 
 PCRE_ERROR_SHORTUTF8 is returned instead
+Line 1962 
 PCRE_ERROR_SHORTUTF8 is returned instead
  .sp
    PCRE_ERROR_BADUTF8_OFFSET (-11)
  .sp
  The UTF-8 byte sequence that was passed as a subject was checked and found to
  be valid (the PCRE_NO_UTF8_CHECK option was not set), but the value of
  \fIstartoffset\fP did not point to the beginning of a UTF-8 character or the
  end of the subject.
-Line 1865 
 retained for backwards compatibility.
+Line 2017 
 retained for backwards compatibility.
  .sp
    PCRE_ERROR_RECURSELOOP    (-26)
  .sp
  This error is returned when \fBpcre_exec()\fP detects a recursion loop within
  the pattern. Specifically, it means that either the whole pattern or a
  subpattern has been called recursively for the second time at the same position
  in the subject string. Some simple patterns that might do this are detected and
  faulted at compile time, but more complicated cases, in particular mutual
  recursions between two different subpatterns, cannot be detected until run
  time.
+ .sp
+   PCRE_ERROR_JIT_STACKLIMIT (-27)
+ .sp
+ This error is returned when a pattern that was successfully studied using the
+ PCRE_STUDY_JIT_COMPILE option is being matched, but the memory available for
+ the just-in-time processing stack is not large enough. See the
+ .\" HREF
+ \fBpcrejit\fP
+ .\"
+ documentation for more details.
  .P
  Error numbers -16 to -20 and -22 are not used by \fBpcre_exec()\fP.
  .
-Line 1880 
 Error numbers -16 to -20 and -22 are not
+Line 2042 
 Error numbers -16 to -20 and -22 are not
  .SS "Reason codes for invalid UTF-8 strings"
  .rs
  .sp
  When \fBpcre_exec()\fP returns either PCRE_ERROR_BADUTF8 or
  PCRE_ERROR_SHORTUTF8, and the size of the output vector (\fIovecsize\fP) is at
  least 2, the offset of the start of the invalid UTF-8 character is placed in
  the first output vector element (\fIovector[0]\fP) and a reason code is placed
  in the second element (\fIovector[1]\fP). The reason codes are given names in
  the \fBpcre.h\fP header file:
  .sp
-Line 1893 
 the \fBpcre.h\fP header file:
+Line 2055 
 the \fBpcre.h\fP header file:
    PCRE_UTF8_ERR4
    PCRE_UTF8_ERR5
  .sp
  The string ends with a truncated UTF-8 character; the code specifies how many
  bytes are missing (1 to 5). Although RFC 3629 restricts UTF-8 characters to be
  no longer than 4 bytes, the encoding scheme (originally defined by RFC 2279)
  allows for up to 6 bytes, and this is checked first; hence the possibility of
 or 5 missing bytes.
  .sp
    PCRE_UTF8_ERR6
-Line 1905 
 allows for up to 6 bytes, and this is ch
+Line 2067 
 allows for up to 6 bytes, and this is ch
    PCRE_UTF8_ERR9
    PCRE_UTF8_ERR10
  .sp
  The two most significant bits of the 2nd, 3rd, 4th, 5th, or 6th byte of the
  character do not have the binary value 0b10 (that is, either the most
  significant bit is 0, or the next bit is 1).
  .sp
    PCRE_UTF8_ERR11
    PCRE_UTF8_ERR12
  .sp
  A character that is valid by the RFC 2279 rules is either 5 or 6 bytes long;
  these code points are excluded by RFC 3629.
  .sp
    PCRE_UTF8_ERR13
  .sp
  A 4-byte character has a value greater than 0x10fff; these code points are
  excluded by RFC 3629.
  .sp
    PCRE_UTF8_ERR14
  .sp
  A 3-byte character has a value in the range 0xd800 to 0xdfff; this range of
  code points are reserved by RFC 3629 for use with UTF-16, and so are excluded
  from UTF-8.
  .sp
    PCRE_UTF8_ERR15
    PCRE_UTF8_ERR16
    PCRE_UTF8_ERR17
    PCRE_UTF8_ERR18
    PCRE_UTF8_ERR19
  .sp
  A 2-, 3-, 4-, 5-, or 6-byte character is "overlong", that is, it codes for a
  value that can be represented by fewer bytes, which is invalid. For example,
  the two bytes 0xc0, 0xae give the value 0x2e, whose correct coding uses just
  one byte.
  .sp
    PCRE_UTF8_ERR20
  .sp
  The two most significant bits of the first byte of a character have the binary
  value 0b10 (that is, the most significant bit is 1 and the second is 0). Such a
  byte can only validly occur as the second or subsequent byte of a multi-byte
  character.
  .sp
-Line 2112 
 names are not included in the compiled c
+Line 2274 
 names are not included in the compiled c
  numbers. For this reason, the use of different names for subpatterns of the
  same number causes an error at compile time.
  .
+ .
  .SH "DUPLICATE SUBPATTERN NAMES"
  .rs
  .sp
-Line 2311 
 returns data, even though the meaning of
+Line 2474 
 returns data, even though the meaning of
  The strings are returned in reverse order of length; that is, the longest
  matching string is given first. If there were too many matches to fit into
  \fIovector\fP, the yield of the function is zero, and the vector is filled with
- the longest matches.
+ the longest matches. Unlike \fBpcre_exec()\fP, \fBpcre_dfa_exec()\fP can use
+ the entire \fIovector\fP for returning matched strings.
  .
  .
  .SS "Error returns from \fBpcre_dfa_exec()\fP"
-Line 2341 
 group. These are not supported.
+Line 2505 
 group. These are not supported.
    PCRE_ERROR_DFA_UMLIMIT    (-18)
  .sp
  This return is given if \fBpcre_dfa_exec()\fP is called with an \fIextra\fP
- block that contains a setting of the \fImatch_limit\fP field. This is not
+ block that contains a setting of the \fImatch_limit\fP or
- supported (it is meaningless).
+ \fImatch_limit_recursion\fP fields. This is not supported (these fields are
+ meaningless for DFA matching).
  .sp
    PCRE_ERROR_DFA_WSSIZE     (-19)
  .sp
-Line 2379 
 Cambridge CB2 3QH, England.
+Line 2544 
 Cambridge CB2 3QH, England.
  .rs
  .sp
  .nf
- Last updated: 28 July 2011
+ Last updated: 14 November 2011
  Copyright (c) 1997-2011 University of Cambridge.
  .fi

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