Spec update.

[users/heiko/exim.git] / doc / doc-txt / pcretest.txt

diff --git a/doc/doc-txt/pcretest.txt b/doc/doc-txt/pcretest.txt
index 9e9b70ef4b0af06f42225bcc22dc898fc10aad28..dfa03b80bef6e0eb5e769f3cee0d08eaaacf7cb3 100644 (file)
--- a/doc/doc-txt/pcretest.txt
+++ b/doc/doc-txt/pcretest.txt
@@ -1,19 +1,18 @@
-This file contains the PCRE man page that described the pcretest program. Note 
-that not all of the features of PCRE are available in the limited version that 
+This file contains the PCRE man page that described the pcretest program. Note
+that not all of the features of PCRE are available in the limited version that

 is built with Exim.
 -------------------------------------------------------------------------------
 
 PCRETEST(1)                                                        PCRETEST(1)
 
 
 is built with Exim.
 -------------------------------------------------------------------------------
 
 PCRETEST(1)                                                        PCRETEST(1)
 
 

-

 NAME
        pcretest - a program for testing Perl-compatible regular expressions.
 
 NAME
        pcretest - a program for testing Perl-compatible regular expressions.
 

+

 SYNOPSIS
 
 SYNOPSIS
 

-       pcretest [-C] [-d] [-i] [-m] [-o osize] [-p] [-t] [source]
-            [destination]
+       pcretest [options] [source] [destination]

 
        pcretest  was written as a test program for the PCRE regular expression
        library itself, but it can also be used for experimenting with  regular
 
        pcretest  was written as a test program for the PCRE regular expression
        library itself, but it can also be used for experimenting with  regular


@@ -29,55 +28,67 @@ OPTIONS
                  able   information  about  the  optional  features  that  are
                  included, and then exit.
 
                  able   information  about  the  optional  features  that  are
                  included, and then exit.
 

-       -d        Behave as if each regex had  the  /D  (debug)  modifier;  the
+       -d        Behave as if each regex has  the  /D  (debug)  modifier;  the

                  internal form is output after compilation.
 
                  internal form is output after compilation.
 

-       -i        Behave  as  if  each  regex  had the /I modifier; information
+       -dfa      Behave  as if each data line contains the \D escape sequence;
+                 this    causes    the    alternative    matching    function,
+                 pcre_dfa_exec(),   to   be   used  instead  of  the  standard
+                 pcre_exec() function (more detail is given below).
+
+       -i        Behave as if each regex  has  the  /I  modifier;  information

                  about the compiled pattern is given after compilation.
 
                  about the compiled pattern is given after compilation.
 

-       -m        Output the size of each compiled pattern after  it  has  been
-                 compiled.  This  is  equivalent  to adding /M to each regular
-                 expression.  For  compatibility  with  earlier  versions   of
+       -m        Output  the  size  of each compiled pattern after it has been
+                 compiled. This is equivalent to adding  /M  to  each  regular
+                 expression.   For  compatibility  with  earlier  versions  of

                  pcretest, -s is a synonym for -m.
 
                  pcretest, -s is a synonym for -m.
 

-       -o osize  Set  the number of elements in the output vector that is used
-                 when calling pcre_exec() to be osize. The  default  value  is
+       -o osize  Set the number of elements in the output vector that is  used
+                 when  calling  pcre_exec()  to be osize. The default value is

                  45, which is enough for 14 capturing subexpressions. The vec-
                  45, which is enough for 14 capturing subexpressions. The vec-

-                 tor size can be changed  for  individual  matching  calls  by
+                 tor  size  can  be  changed  for individual matching calls by

                  including \O in the data line (see below).
 
                  including \O in the data line (see below).
 

-       -p        Behave  as  if  each regex has /P modifier; the POSIX wrapper
-                 API is used to call PCRE. None of the other options  has  any
-                 effect when -p is set.
+       -p        Behave as if each regex has the /P modifier; the POSIX  wrap-
+                 per  API  is used to call PCRE. None of the other options has
+                 any effect when -p is set.
+
+       -q        Do not output the version number of pcretest at the start  of
+                 execution.

 
 

-       -t        Run  each  compile, study, and match many times with a timer,
-                 and output resulting time per compile or match (in  millisec-
-                 onds).  Do  not set -m with -t, because you will then get the
-                 size output a zillion times, and  the  timing  will  be  dis-
+       -S size   On  Unix-like  systems,  set the size of the runtime stack to
+                 size megabytes.
+
+       -t        Run each compile, study, and match many times with  a  timer,
+                 and  output resulting time per compile or match (in millisec-
+                 onds). Do not set -m with -t, because you will then  get  the
+                 size  output  a  zillion  times,  and the timing will be dis-

                  torted.
 
 
 DESCRIPTION
 
                  torted.
 
 
 DESCRIPTION
 

-       If  pcretest  is  given two filename arguments, it reads from the first
+       If pcretest is given two filename arguments, it reads  from  the  first

        and writes to the second. If it is given only one filename argument, it
        and writes to the second. If it is given only one filename argument, it

-       reads  from  that  file  and writes to stdout. Otherwise, it reads from
-       stdin and writes to stdout, and prompts for each line of  input,  using
+       reads from that file and writes to stdout.  Otherwise,  it  reads  from
+       stdin  and  writes to stdout, and prompts for each line of input, using

        "re>" to prompt for regular expressions, and "data>" to prompt for data
        lines.
 
        The program handles any number of sets of input on a single input file.
        "re>" to prompt for regular expressions, and "data>" to prompt for data
        lines.
 
        The program handles any number of sets of input on a single input file.

-       Each  set starts with a regular expression, and continues with any num-
+       Each set starts with a regular expression, and continues with any  num-

        ber of data lines to be matched against the pattern.
 
        ber of data lines to be matched against the pattern.
 

-       Each data line is matched separately and independently. If you want  to
-       do  multiple-line  matches, you have to use the \n escape sequence in a
-       single line of input to encode  the  newline  characters.  The  maximum
-       length of data line is 30,000 characters.
+       Each  data line is matched separately and independently. If you want to
+       do multi-line matches, you have to use the \n escape sequence (or \r or
+       \r\n,  depending  on  the newline setting) in a single line of input to
+       encode the newline characters. There is no limit on the length of  data
+       lines; the input buffer is automatically extended if it is too small.

 
        An  empty  line signals the end of the data lines, at which point a new
        regular expression is read. The regular expressions are given  enclosed
 
        An  empty  line signals the end of the data lines, at which point a new
        regular expression is read. The regular expressions are given  enclosed

-       in any non-alphanumeric delimiters other than backslash, for example
+       in any non-alphanumeric delimiters other than backslash, for example:

 
          /(a|bc)x+yz/
 
 
          /(a|bc)x+yz/
 


@@ -125,12 +136,23 @@ PATTERN MODIFIERS
        The following table shows additional modifiers for setting PCRE options
        that do not correspond to anything in Perl:
 
        The following table shows additional modifiers for setting PCRE options
        that do not correspond to anything in Perl:
 

-         /A    PCRE_ANCHORED
-         /C    PCRE_AUTO_CALLOUT
-         /E    PCRE_DOLLAR_ENDONLY
-         /N    PCRE_NO_AUTO_CAPTURE
-         /U    PCRE_UNGREEDY
-         /X    PCRE_EXTRA
+         /A       PCRE_ANCHORED
+         /C       PCRE_AUTO_CALLOUT
+         /E       PCRE_DOLLAR_ENDONLY
+         /f       PCRE_FIRSTLINE
+         /J       PCRE_DUPNAMES
+         /N       PCRE_NO_AUTO_CAPTURE
+         /U       PCRE_UNGREEDY
+         /X       PCRE_EXTRA
+         /<cr>    PCRE_NEWLINE_CR
+         /<lf>    PCRE_NEWLINE_LF
+         /<crlf>  PCRE_NEWLINE_CRLF
+
+       Those specifying line endings are literal strings as shown. Details  of
+       the  meanings of these PCRE options are given in the pcreapi documenta-
+       tion.
+
+   Finding all matches in a string

 
        Searching for all possible matches within each subject  string  can  be
        requested  by  the  /g  or  /G modifier. After finding a match, PCRE is
 
        Searching for all possible matches within each subject  string  can  be
        requested  by  the  /g  or  /G modifier. After finding a match, PCRE is


@@ -149,6 +171,8 @@ PATTERN MODIFIERS
        one, and the normal match is retried. This imitates the way  Perl  han-
        dles such cases when using the /g modifier or the split() function.
 
        one, and the normal match is retried. This imitates the way  Perl  han-
        dles such cases when using the /g modifier or the split() function.
 

+   Other modifiers
+

        There are yet more modifiers for controlling the way pcretest operates.
 
        The /+ modifier requests that as well as outputting the substring  that
        There are yet more modifiers for controlling the way pcretest operates.
 
        The /+ modifier requests that as well as outputting the substring  that


@@ -224,6 +248,8 @@ DATA LINES
          \e         escape
          \f         formfeed
          \n         newline
          \e         escape
          \f         formfeed
          \n         newline

+         \qdd       set the PCRE_MATCH_LIMIT limit to dd
+                      (any number of digits)

          \r         carriage return
          \t         tab
          \v         vertical tab
          \r         carriage return
          \t         tab
          \v         vertical tab


@@ -232,7 +258,9 @@ DATA LINES
          \x{hh...}  hexadecimal character, any number of digits
                       in UTF-8 mode
          \A         pass the PCRE_ANCHORED option to pcre_exec()
          \x{hh...}  hexadecimal character, any number of digits
                       in UTF-8 mode
          \A         pass the PCRE_ANCHORED option to pcre_exec()

+                      or pcre_dfa_exec()

          \B         pass the PCRE_NOTBOL option to pcre_exec()
          \B         pass the PCRE_NOTBOL option to pcre_exec()

+                      or pcre_dfa_exec()

          \Cdd       call pcre_copy_substring() for substring dd
                       after a successful match (number less than 32)
          \Cname     call pcre_copy_named_substring() for substring
          \Cdd       call pcre_copy_substring() for substring dd
                       after a successful match (number less than 32)
          \Cname     call pcre_copy_named_substring() for substring


@@ -247,6 +275,8 @@ DATA LINES
                       reached for the nth time
          \C*n       pass the number n (may be negative) as callout
                       data; this is used as the callout return value
                       reached for the nth time
          \C*n       pass the number n (may be negative) as callout
                       data; this is used as the callout return value

+         \D         use the pcre_dfa_exec() match function
+         \F         only shortest match for pcre_dfa_exec()

          \Gdd       call pcre_get_substring() for substring dd
                       after a successful match (number less than 32)
          \Gname     call pcre_get_named_substring() for substring
          \Gdd       call pcre_get_substring() for substring dd
                       after a successful match (number less than 32)
          \Gname     call pcre_get_named_substring() for substring


@@ -254,47 +284,84 @@ DATA LINES
                       ated by next non-alphanumeric character)
          \L         call pcre_get_substringlist() after a
                       successful match
                       ated by next non-alphanumeric character)
          \L         call pcre_get_substringlist() after a
                       successful match

-         \M         discover the minimum MATCH_LIMIT setting
+         \M         discover the minimum MATCH_LIMIT and
+                      MATCH_LIMIT_RECURSION settings

          \N         pass the PCRE_NOTEMPTY option to pcre_exec()
          \N         pass the PCRE_NOTEMPTY option to pcre_exec()

+                      or pcre_dfa_exec()

          \Odd       set the size of the output vector passed to
                       pcre_exec() to dd (any number of digits)
          \P         pass the PCRE_PARTIAL option to pcre_exec()
          \Odd       set the size of the output vector passed to
                       pcre_exec() to dd (any number of digits)
          \P         pass the PCRE_PARTIAL option to pcre_exec()

+                      or pcre_dfa_exec()
+         \Qdd       set the PCRE_MATCH_LIMIT_RECURSION limit to dd
+                      (any number of digits)
+         \R         pass the PCRE_DFA_RESTART option to pcre_dfa_exec()

          \S         output details of memory get/free calls during matching
          \Z         pass the PCRE_NOTEOL option to pcre_exec()
          \S         output details of memory get/free calls during matching
          \Z         pass the PCRE_NOTEOL option to pcre_exec()

+                      or pcre_dfa_exec()

          \?         pass the PCRE_NO_UTF8_CHECK option to
          \?         pass the PCRE_NO_UTF8_CHECK option to

-                      pcre_exec()
+                      pcre_exec() or pcre_dfa_exec()

          \>dd       start the match at offset dd (any number of digits);
                       this sets the startoffset argument for pcre_exec()
          \>dd       start the match at offset dd (any number of digits);
                       this sets the startoffset argument for pcre_exec()

-
-       A  backslash  followed by anything else just escapes the anything else.
-       If the very last character is a backslash, it is ignored. This gives  a
-       way  of  passing  an empty line as data, since a real empty line termi-
-       nates the data input.
-
-       If \M is present, pcretest calls pcre_exec() several times,  with  dif-
-       ferent  values  in  the match_limit field of the pcre_extra data struc-
-       ture, until it finds the minimum number that is needed for  pcre_exec()
-       to  complete.  This  number is a measure of the amount of recursion and
-       backtracking that takes place, and checking it out can be  instructive.
-       For  most  simple  matches, the number is quite small, but for patterns
-       with very large numbers of matching possibilities, it can become  large
-       very quickly with increasing length of subject string.
+                      or pcre_dfa_exec()
+         \<cr>      pass the PCRE_NEWLINE_CR option to pcre_exec()
+                      or pcre_dfa_exec()
+         \<lf>      pass the PCRE_NEWLINE_LF option to pcre_exec()
+                      or pcre_dfa_exec()
+         \<crlf>    pass the PCRE_NEWLINE_CRLF option to pcre_exec()
+                      or pcre_dfa_exec()
+
+       The  escapes  that specify line endings are literal strings, exactly as
+       shown.  A backslash followed by anything else just escapes the anything
+       else.  If  the  very last character is a backslash, it is ignored. This
+       gives a way of passing an empty line as data, since a real  empty  line
+       terminates the data input.
+
+       If  \M  is present, pcretest calls pcre_exec() several times, with dif-
+       ferent values in the match_limit and  match_limit_recursion  fields  of
+       the  pcre_extra  data structure, until it finds the minimum numbers for
+       each parameter that allow pcre_exec() to complete. The match_limit num-
+       ber  is  a  measure of the amount of backtracking that takes place, and
+       checking it out can be instructive. For most simple matches, the number
+       is  quite  small,  but for patterns with very large numbers of matching
+       possibilities, it can become large very quickly with increasing  length
+       of subject string. The match_limit_recursion number is a measure of how
+       much stack (or, if PCRE is compiled with  NO_RECURSE,  how  much  heap)
+       memory is needed to complete the match attempt.

 
        When  \O  is  used, the value specified may be higher or lower than the
        size set by the -O command line option (or defaulted to 45); \O applies
        only to the call of pcre_exec() for the line in which it appears.
 
        If  the /P modifier was present on the pattern, causing the POSIX wrap-
 
        When  \O  is  used, the value specified may be higher or lower than the
        size set by the -O command line option (or defaulted to 45); \O applies
        only to the call of pcre_exec() for the line in which it appears.
 
        If  the /P modifier was present on the pattern, causing the POSIX wrap-

-       per API to be used, only \B and \Z have any effect, causing  REG_NOTBOL
-       and REG_NOTEOL to be passed to regexec() respectively.
+       per API to be used, the only option-setting  sequences  that  have  any
+       effect  are \B and \Z, causing REG_NOTBOL and REG_NOTEOL, respectively,
+       to be passed to regexec().
+
+       The use of \x{hh...} to represent UTF-8 characters is not dependent  on
+       the  use  of  the  /8 modifier on the pattern. It is recognized always.
+       There may be any number of hexadecimal digits inside  the  braces.  The
+       result  is from one to six bytes, encoded according to the UTF-8 rules.
+
+
+THE ALTERNATIVE MATCHING FUNCTION
+
+       By  default,  pcretest  uses  the  standard  PCRE  matching   function,
+       pcre_exec() to match each data line. From release 6.0, PCRE supports an
+       alternative matching function, pcre_dfa_test(),  which  operates  in  a
+       different  way,  and has some restrictions. The differences between the
+       two functions are described in the pcrematching documentation.

 
 

-       The  use of \x{hh...} to represent UTF-8 characters is not dependent on
-       the use of the /8 modifier on the pattern.  It  is  recognized  always.
-       There  may  be  any number of hexadecimal digits inside the braces. The
-       result is from one to six bytes, encoded according to the UTF-8  rules.
+       If a data line contains the \D escape sequence, or if the command  line
+       contains  the -dfa option, the alternative matching function is called.
+       This function finds all possible matches at a given point. If, however,
+       the  \F escape sequence is present in the data line, it stops after the
+       first match is found. This is always the shortest possible match.

 
 
 
 

-OUTPUT FROM PCRETEST
+DEFAULT OUTPUT FROM PCRETEST
+
+       This section describes the output when the  normal  matching  function,
+       pcre_exec(), is being used.

 
        When a match succeeds, pcretest outputs the list of captured substrings
        that pcre_exec() returns, starting with number 0 for  the  string  that
 
        When a match succeeds, pcretest outputs the list of captured substrings
        that pcre_exec() returns, starting with number 0 for  the  string  that


@@ -347,15 +414,67 @@ OUTPUT FROM PCRETEST
 
        Note that while patterns can be continued over several lines  (a  plain
        ">" prompt is used for continuations), data lines may not. However new-
 
        Note that while patterns can be continued over several lines  (a  plain
        ">" prompt is used for continuations), data lines may not. However new-

-       lines can be included in data by means of the \n escape.
+       lines can be included in data by means of the \n escape (or \r or  \r\n
+       for those newline settings).
+
+
+OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION
+
+       When  the  alternative  matching function, pcre_dfa_exec(), is used (by
+       means of the \D escape sequence or the -dfa command line  option),  the
+       output  consists  of  a list of all the matches that start at the first
+       point in the subject where there is at least one match. For example:
+
+           re> /(tang|tangerine|tan)/
+         data> yellow tangerine\D
+          0: tangerine
+          1: tang
+          2: tan
+
+       (Using the normal matching function on this data  finds  only  "tang".)
+       The  longest matching string is always given first (and numbered zero).
+
+       If /gP is present on  the  pattern,  the  search  for  further  matches
+       resumes at the end of the longest match. For example:
+
+           re> /(tang|tangerine|tan)/g
+         data> yellow tangerine and tangy sultana\D
+          0: tangerine
+          1: tang
+          2: tan
+          0: tang
+          1: tan
+          0: tan
+
+       Since  the  matching  function  does not support substring capture, the
+       escape sequences that are concerned with captured  substrings  are  not
+       relevant.
+
+
+RESTARTING AFTER A PARTIAL MATCH
+
+       When the alternative matching function has given the PCRE_ERROR_PARTIAL
+       return, indicating that the subject partially matched the pattern,  you
+       can  restart  the match with additional subject data by means of the \R
+       escape sequence. For example:
+
+           re> /^?(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)$/
+         data> 23ja\P\D
+         Partial match: 23ja
+         data> n05\R\D
+          0: n05
+
+       For further information about partial  matching,  see  the  pcrepartial
+       documentation.

 
 
 CALLOUTS
 
 
 
 CALLOUTS
 

-       If the pattern contains any callout requests, pcretest's callout  func-
-       tion  is  called  during  matching. By default, it displays the callout
-       number, the start and current positions in  the  text  at  the  callout
-       time, and the next pattern item to be tested. For example, the output
+       If  the pattern contains any callout requests, pcretest's callout func-
+       tion is called during matching. This works  with  both  matching  func-
+       tions. By default, the called function displays the callout number, the
+       start and current positions in the text at the callout  time,  and  the
+       next pattern item to be tested. For example, the output

 
          --->pqrabcdef
            0    ^  ^     \d
 
          --->pqrabcdef
            0    ^  ^     \d


@@ -381,7 +500,7 @@ CALLOUTS
           0: E*
 
        The callout function in pcretest returns zero (carry  on  matching)  by
           0: E*
 
        The callout function in pcretest returns zero (carry  on  matching)  by

-       default, but you can use an \C item in a data line (as described above)
+       default,  but you can use a \C item in a data line (as described above)

        to change this.
 
        Inserting callouts can be helpful when using pcretest to check  compli-
        to change this.
 
        Inserting callouts can be helpful when using pcretest to check  compli-


@@ -447,9 +566,9 @@ SAVING AND RELOADING COMPILED PATTERNS
 
 AUTHOR
 
 
 AUTHOR
 

-       Philip Hazel <ph10@cam.ac.uk>
+       Philip Hazel

        University Computing Service,
        Cambridge CB2 3QG, England.
 
        University Computing Service,
        Cambridge CB2 3QG, England.
 

-Last updated: 10 September 2004
-Copyright (c) 1997-2004 University of Cambridge.
+Last updated: 29 June 2006
+Copyright (c) 1997-2006 University of Cambridge.