/[pcre]/code/trunk/doc/pcretest.txt
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revision 79 by nigel, Sat Feb 24 21:40:52 2007 UTC revision 429 by ph10, Tue Sep 1 16:10:16 2009 UTC
# Line 7  NAME Line 7  NAME
7    
8  SYNOPSIS  SYNOPSIS
9    
10         pcretest [-C] [-d] [-dfa] [-i] [-m] [-o osize] [-p] [-t] [source]         pcretest [options] [source] [destination]
             [destination]  
11    
12         pcretest  was written as a test program for the PCRE regular expression         pcretest  was written as a test program for the PCRE regular expression
13         library itself, but it can also be used for experimenting with  regular         library itself, but it can also be used for experimenting with  regular
# Line 20  SYNOPSIS Line 19  SYNOPSIS
19    
20  OPTIONS  OPTIONS
21    
22           -b        Behave as if each regex has the /B (show bytecode)  modifier;
23                     the internal form is output after compilation.
24    
25         -C        Output the version number of the PCRE library, and all avail-         -C        Output the version number of the PCRE library, and all avail-
26                   able   information  about  the  optional  features  that  are                   able  information  about  the  optional  features  that   are
27                   included, and then exit.                   included, and then exit.
28    
29         -d        Behave as if each regex has  the  /D  (debug)  modifier;  the         -d        Behave  as  if  each  regex  has the /D (debug) modifier; the
30                   internal form is output after compilation.                   internal form and information about the compiled  pattern  is
31                     output after compilation; -d is equivalent to -b -i.
32    
33         -dfa      Behave  as if each data line contains the \D escape sequence;         -dfa      Behave  as if each data line contains the \D escape sequence;
34                   this    causes    the    alternative    matching    function,                   this    causes    the    alternative    matching    function,
35                   pcre_dfa_exec(),   to   be   used  instead  of  the  standard                   pcre_dfa_exec(),   to   be   used  instead  of  the  standard
36                   pcre_exec() function (more detail is given below).                   pcre_exec() function (more detail is given below).
37    
38           -help     Output a brief summary these options and then exit.
39    
40         -i        Behave as if each regex  has  the  /I  modifier;  information         -i        Behave as if each regex  has  the  /I  modifier;  information
41                   about the compiled pattern is given after compilation.                   about the compiled pattern is given after compilation.
42    
43         -m        Output  the  size  of each compiled pattern after it has been         -M        Behave  as if each data line contains the \M escape sequence;
44                   compiled. This is equivalent to adding  /M  to  each  regular                   this causes PCRE to  discover  the  minimum  MATCH_LIMIT  and
45                   expression.   For  compatibility  with  earlier  versions  of                   MATCH_LIMIT_RECURSION settings by calling pcre_exec() repeat-
46                     edly with different limits.
47    
48           -m        Output the size of each compiled pattern after  it  has  been
49                     compiled.  This  is  equivalent  to adding /M to each regular
50                     expression.  For  compatibility  with  earlier  versions   of
51                   pcretest, -s is a synonym for -m.                   pcretest, -s is a synonym for -m.
52    
53         -o osize  Set the number of elements in the output vector that is  used         -o osize  Set  the number of elements in the output vector that is used
54                   when  calling  pcre_exec()  to be osize. The default value is                   when calling pcre_exec() or pcre_dfa_exec() to be osize.  The
55                   45, which is enough for 14 capturing subexpressions. The vec-                   default  value is 45, which is enough for 14 capturing subex-
56                   tor  size  can  be  changed  for individual matching calls by                   pressions  for  pcre_exec()  or  22  different  matches   for
57                   including \O in the data line (see below).                   pcre_dfa_exec().  The vector size can be changed for individ-
58                     ual matching calls by including \O  in  the  data  line  (see
59                     below).
60    
61         -p        Behave as if each regex has the /P modifier; the POSIX  wrap-         -p        Behave  as if each regex has the /P modifier; the POSIX wrap-
62                   per  API  is used to call PCRE. None of the other options has                   per API is used to call PCRE. None of the other  options  has
63                   any effect when -p is set.                   any effect when -p is set.
64    
65         -t        Run each compile, study, and match many times with  a  timer,         -q        Do  not output the version number of pcretest at the start of
66                   and  output resulting time per compile or match (in millisec-                   execution.
67                   onds). Do not set -m with -t, because you will then  get  the  
68                   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
69                   torted.                   size megabytes.
70    
71           -t        Run  each  compile, study, and match many times with a timer,
72                     and output resulting time per compile or match (in  millisec-
73                     onds).  Do  not set -m with -t, because you will then get the
74                     size output a zillion times, and  the  timing  will  be  dis-
75                     torted.  You  can  control  the number of iterations that are
76                     used for timing by following -t with a number (as a  separate
77                     item on the command line). For example, "-t 1000" would iter-
78                     ate 1000 times. The default is to iterate 500000 times.
79    
80           -tm       This is like -t except that it times only the matching phase,
81                     not the compile or study phases.
82    
83    
84  DESCRIPTION  DESCRIPTION
85    
86         If pcretest is given two filename arguments, it reads  from  the  first         If  pcretest  is  given two filename arguments, it reads from the first
87         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
88         reads from that file and writes to stdout.  Otherwise,  it  reads  from         reads  from  that  file  and writes to stdout. Otherwise, it reads from
89         stdin  and  writes to stdout, and prompts for each line of input, using         stdin and writes to stdout, and prompts for each line of  input,  using
90         "re>" to prompt for regular expressions, and "data>" to prompt for data         "re>" to prompt for regular expressions, and "data>" to prompt for data
91         lines.         lines.
92    
93           When pcretest is built, a configuration  option  can  specify  that  it
94           should  be  linked  with the libreadline library. When this is done, if
95           the input is from a terminal, it is read using the readline() function.
96           This  provides line-editing and history facilities. The output from the
97           -help option states whether or not readline() will be used.
98    
99         The program handles any number of sets of input on a single input file.         The program handles any number of sets of input on a single input file.
100         Each set starts with a regular expression, and continues with any  num-         Each  set starts with a regular expression, and continues with any num-
101         ber of data lines to be matched against the pattern.         ber of data lines to be matched against the pattern.
102    
103         Each  data line is matched separately and independently. If you want to         Each data line is matched separately and independently. If you want  to
104         do multiple-line matches, you have to use the \n escape sequence  in  a         do multi-line matches, you have to use the \n escape sequence (or \r or
105         single  line  of  input  to  encode the newline characters. The maximum         \r\n, etc., depending on the newline setting) in a single line of input
106         length of data line is 30,000 characters.         to  encode  the  newline  sequences. There is no limit on the length of
107           data lines; the input buffer is automatically extended  if  it  is  too
108         An empty line signals the end of the data lines, at which point  a  new         small.
109         regular  expression is read. The regular expressions are given enclosed  
110         in any non-alphanumeric delimiters other than backslash, for example         An  empty  line signals the end of the data lines, at which point a new
111           regular expression is read. The regular expressions are given  enclosed
112           in any non-alphanumeric delimiters other than backslash, for example:
113    
114           /(a|bc)x+yz/           /(a|bc)x+yz/
115    
116         White space before the initial delimiter is ignored. A regular  expres-         White  space before the initial delimiter is ignored. A regular expres-
117         sion  may be continued over several input lines, in which case the new-         sion may be continued over several input lines, in which case the  new-
118         line characters are included within it. It is possible to  include  the         line  characters  are included within it. It is possible to include the
119         delimiter within the pattern by escaping it, for example         delimiter within the pattern by escaping it, for example
120    
121           /abc\/def/           /abc\/def/
122    
123         If  you  do  so, the escape and the delimiter form part of the pattern,         If you do so, the escape and the delimiter form part  of  the  pattern,
124         but since delimiters are always non-alphanumeric, this does not  affect         but  since delimiters are always non-alphanumeric, this does not affect
125         its  interpretation.   If the terminating delimiter is immediately fol-         its interpretation.  If the terminating delimiter is  immediately  fol-
126         lowed by a backslash, for example,         lowed by a backslash, for example,
127    
128           /abc/\           /abc/\
129    
130         then a backslash is added to the end of the pattern. This  is  done  to         then  a  backslash  is added to the end of the pattern. This is done to
131         provide  a  way of testing the error condition that arises if a pattern         provide a way of testing the error condition that arises if  a  pattern
132         finishes with a backslash, because         finishes with a backslash, because
133    
134           /abc\/           /abc\/
135    
136         is interpreted as the first line of a pattern that starts with  "abc/",         is  interpreted as the first line of a pattern that starts with "abc/",
137         causing pcretest to read the next line as a continuation of the regular         causing pcretest to read the next line as a continuation of the regular
138         expression.         expression.
139    
140    
141  PATTERN MODIFIERS  PATTERN MODIFIERS
142    
143         A pattern may be followed by any number of modifiers, which are  mostly         A  pattern may be followed by any number of modifiers, which are mostly
144         single  characters.  Following  Perl usage, these are referred to below         single characters. Following Perl usage, these are  referred  to  below
145         as, for example, "the /i modifier", even though the  delimiter  of  the         as,  for  example,  "the /i modifier", even though the delimiter of the
146         pattern  need  not always be a slash, and no slash is used when writing         pattern need not always be a slash, and no slash is used  when  writing
147         modifiers. Whitespace may appear between the  final  pattern  delimiter         modifiers.  Whitespace  may  appear between the final pattern delimiter
148         and the first modifier, and between the modifiers themselves.         and the first modifier, and between the modifiers themselves.
149    
150         The /i, /m, /s, and /x modifiers set the PCRE_CASELESS, PCRE_MULTILINE,         The /i, /m, /s, and /x modifiers set the PCRE_CASELESS, PCRE_MULTILINE,
151         PCRE_DOTALL, or PCRE_EXTENDED  options,  respectively,  when  pcre_com-         PCRE_DOTALL,  or  PCRE_EXTENDED  options,  respectively, when pcre_com-
152         pile()  is  called. These four modifier letters have the same effect as         pile() is called. These four modifier letters have the same  effect  as
153         they do in Perl. For example:         they do in Perl. For example:
154    
155           /caseless/i           /caseless/i
# Line 125  PATTERN MODIFIERS Line 157  PATTERN MODIFIERS
157         The following table shows additional modifiers for setting PCRE options         The following table shows additional modifiers for setting PCRE options
158         that do not correspond to anything in Perl:         that do not correspond to anything in Perl:
159    
160           /A    PCRE_ANCHORED           /A              PCRE_ANCHORED
161           /C    PCRE_AUTO_CALLOUT           /C              PCRE_AUTO_CALLOUT
162           /E    PCRE_DOLLAR_ENDONLY           /E              PCRE_DOLLAR_ENDONLY
163           /f    PCRE_FIRSTLINE           /f              PCRE_FIRSTLINE
164           /N    PCRE_NO_AUTO_CAPTURE           /J              PCRE_DUPNAMES
165           /U    PCRE_UNGREEDY           /N              PCRE_NO_AUTO_CAPTURE
166           /X    PCRE_EXTRA           /U              PCRE_UNGREEDY
167             /X              PCRE_EXTRA
168             /<JS>           PCRE_JAVASCRIPT_COMPAT
169             /<cr>           PCRE_NEWLINE_CR
170             /<lf>           PCRE_NEWLINE_LF
171             /<crlf>         PCRE_NEWLINE_CRLF
172             /<anycrlf>      PCRE_NEWLINE_ANYCRLF
173             /<any>          PCRE_NEWLINE_ANY
174             /<bsr_anycrlf>  PCRE_BSR_ANYCRLF
175             /<bsr_unicode>  PCRE_BSR_UNICODE
176    
177           Those specifying line ending sequences are literal  strings  as  shown,
178           but  the  letters  can  be  in either case. This example sets multiline
179           matching with CRLF as the line ending sequence:
180    
181             /^abc/m<crlf>
182    
183           Details of the meanings of these PCRE options are given in the  pcreapi
184           documentation.
185    
186       Finding all matches in a string
187    
188         Searching  for  all  possible matches within each subject string can be         Searching  for  all  possible matches within each subject string can be
189         requested by the /g or /G modifier. After  finding  a  match,  PCRE  is         requested by the /g or /G modifier. After  finding  a  match,  PCRE  is
# Line 150  PATTERN MODIFIERS Line 202  PATTERN MODIFIERS
202         one,  and  the normal match is retried. This imitates the way Perl han-         one,  and  the normal match is retried. This imitates the way Perl han-
203         dles such cases when using the /g modifier or the split() function.         dles such cases when using the /g modifier or the split() function.
204    
205       Other modifiers
206    
207         There are yet more modifiers for controlling the way pcretest operates.         There are yet more modifiers for controlling the way pcretest operates.
208    
209         The  /+ modifier requests that as well as outputting the substring that         The /+ modifier requests that as well as outputting the substring  that
210         matched the entire pattern, pcretest  should  in  addition  output  the         matched  the  entire  pattern,  pcretest  should in addition output the
211         remainder  of  the  subject  string. This is useful for tests where the         remainder of the subject string. This is useful  for  tests  where  the
212         subject contains multiple copies of the same substring.         subject contains multiple copies of the same substring.
213    
214           The  /B modifier is a debugging feature. It requests that pcretest out-
215           put a representation of the compiled byte code after compilation.  Nor-
216           mally  this  information contains length and offset values; however, if
217           /Z is also present, this data is replaced by spaces. This is a  special
218           feature for use in the automatic test scripts; it ensures that the same
219           output is generated for different internal link sizes.
220    
221         The /L modifier must be followed directly by the name of a locale,  for         The /L modifier must be followed directly by the name of a locale,  for
222         example,         example,
223    
# Line 175  PATTERN MODIFIERS Line 236  PATTERN MODIFIERS
236         pattern.  If  the pattern is studied, the results of that are also out-         pattern.  If  the pattern is studied, the results of that are also out-
237         put.         put.
238    
239         The /D modifier is a PCRE debugging feature, which also assumes /I.  It         The /D modifier is a PCRE debugging feature, and is equivalent to  /BI,
240         causes  the  internal form of compiled regular expressions to be output         that is, both the /B and the /I modifiers.
        after compilation. If the pattern was studied, the information returned  
        is also output.  
241    
242         The /F modifier causes pcretest to flip the byte order of the fields in         The /F modifier causes pcretest to flip the byte order of the fields in
243         the compiled pattern that  contain  2-byte  and  4-byte  numbers.  This         the compiled pattern that  contain  2-byte  and  4-byte  numbers.  This
# Line 191  PATTERN MODIFIERS Line 250  PATTERN MODIFIERS
250         The  /S  modifier causes pcre_study() to be called after the expression         The  /S  modifier causes pcre_study() to be called after the expression
251         has been compiled, and the results used when the expression is matched.         has been compiled, and the results used when the expression is matched.
252    
253         The  /M  modifier causes the size of memory block used to hold the com-         The /M modifier causes the size of memory block used to hold  the  com-
254         piled pattern to be output.         piled pattern to be output.
255    
256         The /P modifier causes pcretest to call PCRE via the POSIX wrapper  API         The  /P modifier causes pcretest to call PCRE via the POSIX wrapper API
257         rather  than  its  native  API.  When this is done, all other modifiers         rather than its native API. When this  is  done,  all  other  modifiers
258         except /i, /m, and /+ are ignored. REG_ICASE is set if /i  is  present,         except  /i,  /m, and /+ are ignored. REG_ICASE is set if /i is present,
259         and  REG_NEWLINE  is  set if /m is present. The wrapper functions force         and REG_NEWLINE is set if /m is present. The  wrapper  functions  force
260         PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless REG_NEWLINE is  set.         PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless REG_NEWLINE is set.
261    
262         The  /8 modifier causes pcretest to call PCRE with the PCRE_UTF8 option         The  /8 modifier causes pcretest to call PCRE with the PCRE_UTF8 option
263         set. This turns on support for UTF-8 character handling in  PCRE,  pro-         set. This turns on support for UTF-8 character handling in  PCRE,  pro-
# Line 220  DATA LINES Line 279  DATA LINES
279         nary"  regular  expressions,  you probably don't need any of these. The         nary"  regular  expressions,  you probably don't need any of these. The
280         following escapes are recognized:         following escapes are recognized:
281    
282           \a         alarm (= BEL)           \a         alarm (BEL, \x07)
283           \b         backspace           \b         backspace (\x08)
284           \e         escape           \e         escape (\x27)
285           \f         formfeed           \f         formfeed (\x0c)
286           \n         newline           \n         newline (\x0a)
287           \r         carriage return           \qdd       set the PCRE_MATCH_LIMIT limit to dd
288           \t         tab                        (any number of digits)
289           \v         vertical tab           \r         carriage return (\x0d)
290             \t         tab (\x09)
291             \v         vertical tab (\x0b)
292           \nnn       octal character (up to 3 octal digits)           \nnn       octal character (up to 3 octal digits)
293           \xhh       hexadecimal character (up to 2 hex digits)           \xhh       hexadecimal character (up to 2 hex digits)
294           \x{hh...}  hexadecimal character, any number of digits           \x{hh...}  hexadecimal character, any number of digits
295                        in UTF-8 mode                        in UTF-8 mode
296           \A         pass the PCRE_ANCHORED option to pcre_exec()           \A         pass the PCRE_ANCHORED option to pcre_exec()
297                          or pcre_dfa_exec()
298           \B         pass the PCRE_NOTBOL option to pcre_exec()           \B         pass the PCRE_NOTBOL option to pcre_exec()
299                          or pcre_dfa_exec()
300           \Cdd       call pcre_copy_substring() for substring dd           \Cdd       call pcre_copy_substring() for substring dd
301                        after a successful match (number less than 32)                        after a successful match (number less than 32)
302           \Cname     call pcre_copy_named_substring() for substring           \Cname     call pcre_copy_named_substring() for substring
# Line 257  DATA LINES Line 320  DATA LINES
320                        ated by next non-alphanumeric character)                        ated by next non-alphanumeric character)
321           \L         call pcre_get_substringlist() after a           \L         call pcre_get_substringlist() after a
322                        successful match                        successful match
323           \M         discover the minimum MATCH_LIMIT setting           \M         discover the minimum MATCH_LIMIT and
324                          MATCH_LIMIT_RECURSION settings
325           \N         pass the PCRE_NOTEMPTY option to pcre_exec()           \N         pass the PCRE_NOTEMPTY option to pcre_exec()
326                          or pcre_dfa_exec()
327           \Odd       set the size of the output vector passed to           \Odd       set the size of the output vector passed to
328                        pcre_exec() to dd (any number of digits)                        pcre_exec() to dd (any number of digits)
329           \P         pass the PCRE_PARTIAL option to pcre_exec()           \P         pass the PCRE_PARTIAL_SOFT option to pcre_exec()
330                        or pcre_dfa_exec()                        or pcre_dfa_exec(); if used twice, pass the
331                          PCRE_PARTIAL_HARD option
332             \Qdd       set the PCRE_MATCH_LIMIT_RECURSION limit to dd
333                          (any number of digits)
334           \R         pass the PCRE_DFA_RESTART option to pcre_dfa_exec()           \R         pass the PCRE_DFA_RESTART option to pcre_dfa_exec()
335           \S         output details of memory get/free calls during matching           \S         output details of memory get/free calls during matching
336           \Z         pass the PCRE_NOTEOL option to pcre_exec()           \Z         pass the PCRE_NOTEOL option to pcre_exec()
337                          or pcre_dfa_exec()
338           \?         pass the PCRE_NO_UTF8_CHECK option to           \?         pass the PCRE_NO_UTF8_CHECK option to
339                        pcre_exec()                        pcre_exec() or pcre_dfa_exec()
340           \>dd       start the match at offset dd (any number of digits);           \>dd       start the match at offset dd (any number of digits);
341                        this sets the startoffset argument for pcre_exec()                        this sets the startoffset argument for pcre_exec()
342                          or pcre_dfa_exec()
343             \<cr>      pass the PCRE_NEWLINE_CR option to pcre_exec()
344                          or pcre_dfa_exec()
345             \<lf>      pass the PCRE_NEWLINE_LF option to pcre_exec()
346                          or pcre_dfa_exec()
347             \<crlf>    pass the PCRE_NEWLINE_CRLF option to pcre_exec()
348                          or pcre_dfa_exec()
349             \<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to pcre_exec()
350                          or pcre_dfa_exec()
351             \<any>     pass the PCRE_NEWLINE_ANY option to pcre_exec()
352                          or pcre_dfa_exec()
353    
354           The escapes that specify line ending  sequences  are  literal  strings,
355           exactly as shown. No more than one newline setting should be present in
356           any data line.
357    
358         A backslash followed by anything else just escapes the  anything  else.         A backslash followed by anything else just escapes the  anything  else.
359         If  the very last character is a backslash, it is ignored. This gives a         If  the very last character is a backslash, it is ignored. This gives a
# Line 277  DATA LINES Line 361  DATA LINES
361         nates the data input.         nates the data input.
362    
363         If  \M  is present, pcretest calls pcre_exec() several times, with dif-         If  \M  is present, pcretest calls pcre_exec() several times, with dif-
364         ferent values in the match_limit field of the  pcre_extra  data  struc-         ferent values in the match_limit and  match_limit_recursion  fields  of
365         ture,  until it finds the minimum number that is needed for pcre_exec()         the  pcre_extra  data structure, until it finds the minimum numbers for
366         to complete. This number is a measure of the amount  of  recursion  and         each parameter that allow pcre_exec() to complete. The match_limit num-
367         backtracking  that takes place, and checking it out can be instructive.         ber  is  a  measure of the amount of backtracking that takes place, and
368         For most simple matches, the number is quite small,  but  for  patterns         checking it out can be instructive. For most simple matches, the number
369         with  very large numbers of matching possibilities, it can become large         is  quite  small,  but for patterns with very large numbers of matching
370         very quickly with increasing length of subject string.         possibilities, it can become large very quickly with increasing  length
371           of subject string. The match_limit_recursion number is a measure of how
372           much stack (or, if PCRE is compiled with  NO_RECURSE,  how  much  heap)
373           memory is needed to complete the match attempt.
374    
375         When \O is used, the value specified may be higher or  lower  than  the         When  \O  is  used, the value specified may be higher or lower than the
376         size set by the -O command line option (or defaulted to 45); \O applies         size set by the -O command line option (or defaulted to 45); \O applies
377         only to the call of pcre_exec() for the line in which it appears.         only to the call of pcre_exec() for the line in which it appears.
378    
379         If the /P modifier was present on the pattern, causing the POSIX  wrap-         If  the /P modifier was present on the pattern, causing the POSIX wrap-
380         per  API to be used, only \B and \Z have any effect, causing REG_NOTBOL         per API to be used, the only option-setting  sequences  that  have  any
381         and REG_NOTEOL to be passed to regexec() respectively.         effect  are \B and \Z, causing REG_NOTBOL and REG_NOTEOL, respectively,
382           to be passed to regexec().
383    
384         The use of \x{hh...} to represent UTF-8 characters is not dependent  on         The use of \x{hh...} to represent UTF-8 characters is not dependent  on
385         the  use  of  the  /8 modifier on the pattern. It is recognized always.         the  use  of  the  /8 modifier on the pattern. It is recognized always.
386         There may be any number of hexadecimal digits inside  the  braces.  The         There may be any number of hexadecimal digits inside  the  braces.  The
387         result  is from one to six bytes, encoded according to the UTF-8 rules.         result  is  from  one  to  six bytes, encoded according to the original
388           UTF-8 rules of RFC 2279. This allows for  values  in  the  range  0  to
389           0x7FFFFFFF.  Note  that not all of those are valid Unicode code points,
390           or indeed valid UTF-8 characters according to the later  rules  in  RFC
391           3629.
392    
393    
394  THE ALTERNATIVE MATCHING FUNCTION  THE ALTERNATIVE MATCHING FUNCTION
395    
396         By  default,  pcretest  uses  the  standard  PCRE  matching   function,         By   default,  pcretest  uses  the  standard  PCRE  matching  function,
397         pcre_exec() to match each data line. From release 6.0, PCRE supports an         pcre_exec() to match each data line. From release 6.0, PCRE supports an
398         alternative matching function, pcre_dfa_test(),  which  operates  in  a         alternative  matching  function,  pcre_dfa_test(),  which operates in a
399         different  way,  and has some restrictions. The differences between the         different way, and has some restrictions. The differences  between  the
400         two functions are described in the pcrematching documentation.         two functions are described in the pcrematching documentation.
401    
402         If a data line contains the \D escape sequence, or if the command  line         If  a data line contains the \D escape sequence, or if the command line
403         contains  the -dfa option, the alternative matching function is called.         contains the -dfa option, the alternative matching function is  called.
404         This function finds all possible matches at a given point. If, however,         This function finds all possible matches at a given point. If, however,
405         the  \F escape sequence is present in the data line, it stops after the         the \F escape sequence is present in the data line, it stops after  the
406         first match is found. This is always the shortest possible match.         first match is found. This is always the shortest possible match.
407    
408    
409  DEFAULT OUTPUT FROM PCRETEST  DEFAULT OUTPUT FROM PCRETEST
410    
411         This section describes the output when the  normal  matching  function,         This  section  describes  the output when the normal matching function,
412         pcre_exec(), is being used.         pcre_exec(), is being used.
413    
414         When a match succeeds, pcretest outputs the list of captured substrings         When a match succeeds, pcretest outputs the list of captured substrings
415         that pcre_exec() returns, starting with number 0 for  the  string  that         that  pcre_exec()  returns,  starting with number 0 for the string that
416         matched the whole pattern. Otherwise, it outputs "No match" or "Partial         matched the whole pattern. Otherwise, it outputs "No match" or "Partial
417         match" when pcre_exec() returns PCRE_ERROR_NOMATCH  or  PCRE_ERROR_PAR-         match:"  followed  by the partially matching substring when pcre_exec()
418         TIAL,  respectively, and otherwise the PCRE negative error number. Here         returns PCRE_ERROR_NOMATCH  or  PCRE_ERROR_PARTIAL,  respectively,  and
419         is an example of an interactive pcretest run.         otherwise  the  PCRE  negative  error  number. Here is an example of an
420           interactive pcretest run.
421    
422           $ pcretest           $ pcretest
423           PCRE version 5.00 07-Sep-2004           PCRE version 7.0 30-Nov-2006
424    
425             re> /^abc(\d+)/             re> /^abc(\d+)/
426           data> abc123           data> abc123
# Line 336  DEFAULT OUTPUT FROM PCRETEST Line 429  DEFAULT OUTPUT FROM PCRETEST
429           data> xyz           data> xyz
430           No match           No match
431    
432         If the strings contain any non-printing characters, they are output  as         Note that unset capturing substrings that are not followed by one  that
433         \0x  escapes,  or  as \x{...} escapes if the /8 modifier was present on         is  set are not returned by pcre_exec(), and are not shown by pcretest.
434         the pattern. If the pattern has the /+ modifier, the  output  for  sub-         In the following example, there are two capturing substrings, but  when
435         string  0 is followed by the the rest of the subject string, identified         the  first  data  line  is  matched, the second, unset substring is not
436         by "0+" like this:         shown. An "internal" unset substring is shown as "<unset>", as for  the
437           second data line.
438    
439               re> /(a)|(b)/
440             data> a
441              0: a
442              1: a
443             data> b
444              0: b
445              1: <unset>
446              2: b
447    
448           If  the strings contain any non-printing characters, they are output as
449           \0x escapes, or as \x{...} escapes if the /8 modifier  was  present  on
450           the  pattern.  See below for the definition of non-printing characters.
451           If the pattern has the /+ modifier, the output for substring 0 is  fol-
452           lowed  by  the  the rest of the subject string, identified by "0+" like
453           this:
454    
455             re> /cat/+             re> /cat/+
456           data> cataract           data> cataract
# Line 368  DEFAULT OUTPUT FROM PCRETEST Line 478  DEFAULT OUTPUT FROM PCRETEST
478         (that  is,  the return from the extraction function) is given in paren-         (that  is,  the return from the extraction function) is given in paren-
479         theses after each string for \C and \G.         theses after each string for \C and \G.
480    
481         Note that while patterns can be continued over several lines  (a  plain         Note that whereas patterns can be continued over several lines (a plain
482         ">" prompt is used for continuations), data lines may not. However new-         ">" prompt is used for continuations), data lines may not. However new-
483         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,  \r\n,
484           etc., depending on the newline sequence setting).
485    
486    
487  OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION  OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION
488    
489         When the alternative matching function, pcre_dfa_exec(),  is  used  (by         When  the  alternative  matching function, pcre_dfa_exec(), is used (by
490         means  of  the \D escape sequence or the -dfa command line option), the         means of the \D escape sequence or the -dfa command line  option),  the
491         output consists of a list of all the matches that start  at  the  first         output  consists  of  a list of all the matches that start at the first
492         point in the subject where there is at least one match. For example:         point in the subject where there is at least one match. For example:
493    
494             re> /(tang|tangerine|tan)/             re> /(tang|tangerine|tan)/
# Line 386  OUTPUT FROM THE ALTERNATIVE MATCHING FUN Line 497  OUTPUT FROM THE ALTERNATIVE MATCHING FUN
497            1: tang            1: tang
498            2: tan            2: tan
499    
500         (Using  the  normal  matching function on this data finds only "tang".)         (Using the normal matching function on this data  finds  only  "tang".)
501         The longest matching string is always given first (and numbered  zero).         The  longest matching string is always given first (and numbered zero).
502           After a PCRE_ERROR_PARTIAL return, the output is "Partial match:", fol-
503           lowed by the partially matching substring.
504    
505         If  /gP  is  present  on  the  pattern,  the search for further matches         If /g is present on the pattern, the search for further matches resumes
506         resumes at the end of the longest match. For example:         at the end of the longest match. For example:
507    
508             re> /(tang|tangerine|tan)/g             re> /(tang|tangerine|tan)/g
509           data> yellow tangerine and tangy sultana\D           data> yellow tangerine and tangy sultana\D
# Line 413  RESTARTING AFTER A PARTIAL MATCH Line 526  RESTARTING AFTER A PARTIAL MATCH
526         can restart the match with additional subject data by means of  the  \R         can restart the match with additional subject data by means of  the  \R
527         escape sequence. For example:         escape sequence. For example:
528    
529             re> /^?(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)$/             re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
530           data> 23ja\P\D           data> 23ja\P\D
531           Partial match: 23ja           Partial match: 23ja
532           data> n05\R\D           data> n05\R\D
# Line 463  CALLOUTS Line 576  CALLOUTS
576         the pcrecallout documentation.         the pcrecallout documentation.
577    
578    
579    NON-PRINTING CHARACTERS
580    
581           When  pcretest is outputting text in the compiled version of a pattern,
582           bytes other than 32-126 are always treated as  non-printing  characters
583           are are therefore shown as hex escapes.
584    
585           When  pcretest  is  outputting text that is a matched part of a subject
586           string, it behaves in the same way, unless a different locale has  been
587           set  for  the  pattern  (using  the  /L  modifier).  In  this case, the
588           isprint() function to distinguish printing and non-printing characters.
589    
590    
591  SAVING AND RELOADING COMPILED PATTERNS  SAVING AND RELOADING COMPILED PATTERNS
592    
593         The  facilities  described  in  this section are not available when the         The facilities described in this section are  not  available  when  the
594         POSIX inteface to PCRE is being used, that is, when the /P pattern mod-         POSIX inteface to PCRE is being used, that is, when the /P pattern mod-
595         ifier is specified.         ifier is specified.
596    
597         When the POSIX interface is not in use, you can cause pcretest to write         When the POSIX interface is not in use, you can cause pcretest to write
598         a compiled pattern to a file, by following the modifiers with >  and  a         a  compiled  pattern to a file, by following the modifiers with > and a
599         file name.  For example:         file name.  For example:
600    
601           /pattern/im >/some/file           /pattern/im >/some/file
602    
603         See  the pcreprecompile documentation for a discussion about saving and         See the pcreprecompile documentation for a discussion about saving  and
604         re-using compiled patterns.         re-using compiled patterns.
605    
606         The data that is written is binary.  The  first  eight  bytes  are  the         The  data  that  is  written  is  binary. The first eight bytes are the
607         length  of  the  compiled  pattern  data  followed by the length of the         length of the compiled pattern data  followed  by  the  length  of  the
608         optional study data, each written as four  bytes  in  big-endian  order         optional  study  data,  each  written as four bytes in big-endian order
609         (most  significant  byte  first). If there is no study data (either the         (most significant byte first). If there is no study  data  (either  the
610         pattern was not studied, or studying did not return any data), the sec-         pattern was not studied, or studying did not return any data), the sec-
611         ond  length  is  zero. The lengths are followed by an exact copy of the         ond length is zero. The lengths are followed by an exact  copy  of  the
612         compiled pattern. If there is additional study data, this follows imme-         compiled pattern. If there is additional study data, this follows imme-
613         diately  after  the  compiled pattern. After writing the file, pcretest         diately after the compiled pattern. After writing  the  file,  pcretest
614         expects to read a new pattern.         expects to read a new pattern.
615    
616         A saved pattern can be reloaded into pcretest by specifing < and a file         A saved pattern can be reloaded into pcretest by specifing < and a file
617         name  instead  of  a pattern. The name of the file must not contain a <         name instead of a pattern. The name of the file must not  contain  a  <
618         character, as otherwise pcretest will interpret the line as  a  pattern         character,  as  otherwise pcretest will interpret the line as a pattern
619         delimited by < characters.  For example:         delimited by < characters.  For example:
620    
621            re> </some/file            re> </some/file
622           Compiled regex loaded from /some/file           Compiled regex loaded from /some/file
623           No study data           No study data
624    
625         When  the pattern has been loaded, pcretest proceeds to read data lines         When the pattern has been loaded, pcretest proceeds to read data  lines
626         in the usual way.         in the usual way.
627    
628         You can copy a file written by pcretest to a different host and  reload         You  can copy a file written by pcretest to a different host and reload
629         it  there,  even  if the new host has opposite endianness to the one on         it there, even if the new host has opposite endianness to  the  one  on
630         which the pattern was compiled. For example, you can compile on an  i86         which  the pattern was compiled. For example, you can compile on an i86
631         machine and run on a SPARC machine.         machine and run on a SPARC machine.
632    
633         File  names  for  saving and reloading can be absolute or relative, but         File names for saving and reloading can be absolute  or  relative,  but
634         note that the shell facility of expanding a file name that starts  with         note  that the shell facility of expanding a file name that starts with
635         a tilde (~) is not available.         a tilde (~) is not available.
636    
637         The  ability to save and reload files in pcretest is intended for test-         The ability to save and reload files in pcretest is intended for  test-
638         ing and experimentation. It is not intended for production use  because         ing  and experimentation. It is not intended for production use because
639         only  a  single pattern can be written to a file. Furthermore, there is         only a single pattern can be written to a file. Furthermore,  there  is
640         no facility for supplying  custom  character  tables  for  use  with  a         no  facility  for  supplying  custom  character  tables  for use with a
641         reloaded  pattern.  If  the  original  pattern was compiled with custom         reloaded pattern. If the original  pattern  was  compiled  with  custom
642         tables, an attempt to match a subject string using a  reloaded  pattern         tables,  an  attempt to match a subject string using a reloaded pattern
643         is  likely to cause pcretest to crash.  Finally, if you attempt to load         is likely to cause pcretest to crash.  Finally, if you attempt to  load
644         a file that is not in the correct format, the result is undefined.         a file that is not in the correct format, the result is undefined.
645    
646    
647    SEE ALSO
648    
649           pcre(3),  pcreapi(3),  pcrecallout(3), pcrematching(3), pcrepartial(d),
650           pcrepattern(3), pcreprecompile(3).
651    
652    
653  AUTHOR  AUTHOR
654    
655         Philip Hazel         Philip Hazel
656         University Computing Service,         University Computing Service
657         Cambridge CB2 3QG, England.         Cambridge CB2 3QH, England.
658    
659    
660    REVISION
661    
662  Last updated: 28 February 2005         Last updated: 29 August 2009
663  Copyright (c) 1997-2005 University of Cambridge.         Copyright (c) 1997-2009 University of Cambridge.

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