/[pcre]/code/trunk/doc/pcretest.txt
ViewVC logotype

Diff of /code/trunk/doc/pcretest.txt

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 461 by ph10, Mon Oct 5 10:59:35 2009 UTC revision 518 by ph10, Tue May 18 15:47:01 2010 UTC
# Line 157  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             /8              PCRE_UTF8
161             /?              PCRE_NO_UTF8_CHECK
162           /A              PCRE_ANCHORED           /A              PCRE_ANCHORED
163           /C              PCRE_AUTO_CALLOUT           /C              PCRE_AUTO_CALLOUT
164           /E              PCRE_DOLLAR_ENDONLY           /E              PCRE_DOLLAR_ENDONLY
# Line 164  PATTERN MODIFIERS Line 166  PATTERN MODIFIERS
166           /J              PCRE_DUPNAMES           /J              PCRE_DUPNAMES
167           /N              PCRE_NO_AUTO_CAPTURE           /N              PCRE_NO_AUTO_CAPTURE
168           /U              PCRE_UNGREEDY           /U              PCRE_UNGREEDY
169             /W              PCRE_UCP
170           /X              PCRE_EXTRA           /X              PCRE_EXTRA
171           /<JS>           PCRE_JAVASCRIPT_COMPAT           /<JS>           PCRE_JAVASCRIPT_COMPAT
172           /<cr>           PCRE_NEWLINE_CR           /<cr>           PCRE_NEWLINE_CR
# Line 174  PATTERN MODIFIERS Line 177  PATTERN MODIFIERS
177           /<bsr_anycrlf>  PCRE_BSR_ANYCRLF           /<bsr_anycrlf>  PCRE_BSR_ANYCRLF
178           /<bsr_unicode>  PCRE_BSR_UNICODE           /<bsr_unicode>  PCRE_BSR_UNICODE
179    
180         Those specifying line ending sequences are literal  strings  as  shown,         The modifiers that are enclosed in angle brackets are  literal  strings
181         but  the  letters  can  be  in either case. This example sets multiline         as  shown,  including  the  angle  brackets,  but the letters can be in
182         matching with CRLF as the line ending sequence:         either case. This example sets multiline matching with CRLF as the line
183           ending sequence:
184    
185           /^abc/m<crlf>           /^abc/m<crlf>
186    
187         Details of the meanings of these PCRE options are given in the  pcreapi         As well as turning on the PCRE_UTF8 option, the /8 modifier also causes
188         documentation.         any non-printing characters in output strings to be printed  using  the
189           \x{hh...}  notation  if they are valid UTF-8 sequences. Full details of
190           the PCRE options are given in the pcreapi documentation.
191    
192     Finding all matches in a string     Finding all matches in a string
193    
194         Searching  for  all  possible matches within each subject string can be         Searching for all possible matches within each subject  string  can  be
195         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
196         called again to search the remainder of the subject string. The differ-         called again to search the remainder of the subject string. The differ-
197         ence between /g and /G is that the former uses the startoffset argument         ence between /g and /G is that the former uses the startoffset argument
198         to  pcre_exec()  to  start  searching  at a new point within the entire         to pcre_exec() to start searching at a  new  point  within  the  entire
199         string (which is in effect what Perl does), whereas the  latter  passes         string  (which  is in effect what Perl does), whereas the latter passes
200         over  a  shortened  substring.  This makes a difference to the matching         over a shortened substring. This makes a  difference  to  the  matching
201         process if the pattern begins with a lookbehind assertion (including \b         process if the pattern begins with a lookbehind assertion (including \b
202         or \B).         or \B).
203    
204         If  any  call  to  pcre_exec()  in a /g or /G sequence matches an empty         If any call to pcre_exec() in a /g or  /G  sequence  matches  an  empty
205         string, the next  call  is  done  with  the  PCRE_NOTEMPTY_ATSTART  and         string,  the  next  call  is  done  with  the PCRE_NOTEMPTY_ATSTART and
206         PCRE_ANCHORED  flags  set  in  order  to search for another, non-empty,         PCRE_ANCHORED flags set in order  to  search  for  another,  non-empty,
207         match at the same point. If this second match fails, the  start  offset         match  at  the same point. If this second match fails, the start offset
208         is  advanced  by  one  character, and the normal match is retried. This         is advanced by one character, and the normal  match  is  retried.  This
209         imitates the way Perl handles such cases when using the /g modifier  or         imitates  the way Perl handles such cases when using the /g modifier or
210         the split() function.         the split() function.
211    
212     Other modifiers     Other modifiers
213    
214         There are yet more modifiers for controlling the way pcretest operates.         There are yet more modifiers for controlling the way pcretest operates.
215    
216         The  /+ modifier requests that as well as outputting the substring that         The /+ modifier requests that as well as outputting the substring  that
217         matched the entire pattern, pcretest  should  in  addition  output  the         matched  the  entire  pattern,  pcretest  should in addition output the
218         remainder  of  the  subject  string. This is useful for tests where the         remainder of the subject string. This is useful  for  tests  where  the
219         subject contains multiple copies of the same substring.         subject contains multiple copies of the same substring.
220    
221         The /B modifier is a debugging feature. It requests that pcretest  out-         The  /B modifier is a debugging feature. It requests that pcretest out-
222         put  a representation of the compiled byte code after compilation. Nor-         put a representation of the compiled byte code after compilation.  Nor-
223         mally this information contains length and offset values;  however,  if         mally  this  information contains length and offset values; however, if
224         /Z  is also present, this data is replaced by spaces. This is a special         /Z is also present, this data is replaced by spaces. This is a  special
225         feature for use in the automatic test scripts; it ensures that the same         feature for use in the automatic test scripts; it ensures that the same
226         output is generated for different internal link sizes.         output is generated for different internal link sizes.
227    
228           The /D modifier is a PCRE debugging feature, and is equivalent to  /BI,
229           that is, both the /B and the /I modifiers.
230    
231           The /F modifier causes pcretest to flip the byte order of the fields in
232           the compiled pattern that  contain  2-byte  and  4-byte  numbers.  This
233           facility  is  for testing the feature in PCRE that allows it to execute
234           patterns that were compiled on a host with a different endianness. This
235           feature  is  not  available  when  the POSIX interface to PCRE is being
236           used, that is, when the /P pattern modifier is specified. See also  the
237           section about saving and reloading compiled patterns below.
238    
239           The  /I  modifier  requests  that pcretest output information about the
240           compiled pattern (whether it is anchored, has a fixed first  character,
241           and  so  on). It does this by calling pcre_fullinfo() after compiling a
242           pattern. If the pattern is studied, the results of that are  also  out-
243           put.
244    
245           The  /K modifier requests pcretest to show names from backtracking con-
246           trol verbs that are returned  from  calls  to  pcre_exec().  It  causes
247           pcretest  to create a pcre_extra block if one has not already been cre-
248           ated by a call to pcre_study(), and to set the PCRE_EXTRA_MARK flag and
249           the mark field within it, every time that pcre_exec() is called. If the
250           variable that the mark field points to is non-NULL for  a  match,  non-
251           match, or partial match, pcretest prints the string to which it points.
252           For a match, this is shown on a line by itself, tagged with "MK:".  For
253           a non-match it is added to the message.
254    
255         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
256         example,         example,
257    
# Line 231  PATTERN MODIFIERS Line 264  PATTERN MODIFIERS
264         tables pointer; that is, /L applies only to the expression on which  it         tables pointer; that is, /L applies only to the expression on which  it
265         appears.         appears.
266    
        The  /I  modifier  requests  that pcretest output information about the  
        compiled pattern (whether it is anchored, has a fixed first  character,  
        and  so  on). It does this by calling pcre_fullinfo() after compiling a  
        pattern. If the pattern is studied, the results of that are  also  out-  
        put.  
   
        The  /D modifier is a PCRE debugging feature, and is equivalent to /BI,  
        that is, both the /B and the /I modifiers.  
   
        The /F modifier causes pcretest to flip the byte order of the fields in  
        the  compiled  pattern  that  contain  2-byte  and 4-byte numbers. This  
        facility is for testing the feature in PCRE that allows it  to  execute  
        patterns that were compiled on a host with a different endianness. This  
        feature is not available when the POSIX  interface  to  PCRE  is  being  
        used,  that is, when the /P pattern modifier is specified. See also the  
        section about saving and reloading compiled patterns below.  
   
        The /S modifier causes pcre_study() to be called after  the  expression  
        has been compiled, and the results used when the expression is matched.  
   
267         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-
268         piled pattern to be output.         piled pattern to be output.
269    
# Line 260  PATTERN MODIFIERS Line 273  PATTERN MODIFIERS
273         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
274         PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless REG_NEWLINE is set.         PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless REG_NEWLINE is set.
275    
276         The /8 modifier causes pcretest to call PCRE with the PCRE_UTF8  option         The /S modifier causes pcre_study() to be called after  the  expression
277         set.  This  turns on support for UTF-8 character handling in PCRE, pro-         has been compiled, and the results used when the expression is matched.
        vided that it was compiled with this  support  enabled.  This  modifier  
        also causes any non-printing characters in output strings to be printed  
        using the \x{hh...} notation if they are valid UTF-8 sequences.  
   
        If the /? modifier  is  used  with  /8,  it  causes  pcretest  to  call  
        pcre_compile()  with  the  PCRE_NO_UTF8_CHECK  option,  to suppress the  
        checking of the string for UTF-8 validity.  
278    
279    
280  DATA LINES  DATA LINES
281    
282         Before each data line is passed to pcre_exec(),  leading  and  trailing         Before  each  data  line is passed to pcre_exec(), leading and trailing
283         whitespace  is  removed,  and it is then scanned for \ escapes. Some of         whitespace is removed, and it is then scanned for \  escapes.  Some  of
284         these are pretty esoteric features, intended for checking out  some  of         these  are  pretty esoteric features, intended for checking out some of
285         the  more  complicated features of PCRE. If you are just testing "ordi-         the more complicated features of PCRE. If you are just  testing  "ordi-
286         nary" regular expressions, you probably don't need any  of  these.  The         nary"  regular  expressions,  you probably don't need any of these. The
287         following escapes are recognized:         following escapes are recognized:
288    
289           \a         alarm (BEL, \x07)           \a         alarm (BEL, \x07)
# Line 355  DATA LINES Line 361  DATA LINES
361           \<any>     pass the PCRE_NEWLINE_ANY option to pcre_exec()           \<any>     pass the PCRE_NEWLINE_ANY option to pcre_exec()
362                        or pcre_dfa_exec()                        or pcre_dfa_exec()
363    
364         The  escapes  that  specify  line ending sequences are literal strings,         The escapes that specify line ending  sequences  are  literal  strings,
365         exactly as shown. No more than one newline setting should be present in         exactly as shown. No more than one newline setting should be present in
366         any data line.         any data line.
367    
368         A  backslash  followed by anything else just escapes the anything else.         A backslash followed by anything else just escapes the  anything  else.
369         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
370         way  of  passing  an empty line as data, since a real empty line termi-         way of passing an empty line as data, since a real  empty  line  termi-
371         nates the data input.         nates the data input.
372    
373         If \M is present, pcretest calls pcre_exec() several times,  with  dif-         If  \M  is present, pcretest calls pcre_exec() several times, with dif-
374         ferent  values  in  the match_limit and match_limit_recursion fields of         ferent values in the match_limit and  match_limit_recursion  fields  of
375         the pcre_extra data structure, until it finds the minimum  numbers  for         the  pcre_extra  data structure, until it finds the minimum numbers for
376         each parameter that allow pcre_exec() to complete. The match_limit num-         each parameter that allow pcre_exec() to complete. The match_limit num-
377         ber is a measure of the amount of backtracking that  takes  place,  and         ber  is  a  measure of the amount of backtracking that takes place, and
378         checking it out can be instructive. For most simple matches, the number         checking it out can be instructive. For most simple matches, the number
379         is quite small, but for patterns with very large  numbers  of  matching         is  quite  small,  but for patterns with very large numbers of matching
380         possibilities,  it can become large very quickly with increasing length         possibilities, it can become large very quickly with increasing  length
381         of subject string. The match_limit_recursion number is a measure of how         of subject string. The match_limit_recursion number is a measure of how
382         much  stack  (or,  if  PCRE is compiled with NO_RECURSE, how much heap)         much stack (or, if PCRE is compiled with  NO_RECURSE,  how  much  heap)
383         memory is needed to complete the match attempt.         memory is needed to complete the match attempt.
384    
385         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
386         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
387         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.
388    
389         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-
390         per  API  to  be  used, the only option-setting sequences that have any         per API to be used, the only option-setting  sequences  that  have  any
391         effect are \B and \Z, causing REG_NOTBOL and REG_NOTEOL,  respectively,         effect  are \B and \Z, causing REG_NOTBOL and REG_NOTEOL, respectively,
392         to be passed to regexec().         to be passed to regexec().
393    
394         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
395         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.
396         There  may  be  any number of hexadecimal digits inside the braces. The         There may be any number of hexadecimal digits inside  the  braces.  The
397         result is from one to six bytes,  encoded  according  to  the  original         result  is  from  one  to  six bytes, encoded according to the original
398         UTF-8  rules  of  RFC  2279.  This  allows for values in the range 0 to         UTF-8 rules of RFC 2279. This allows for  values  in  the  range  0  to
399         0x7FFFFFFF. Note that not all of those are valid Unicode  code  points,         0x7FFFFFFF.  Note  that not all of those are valid Unicode code points,
400         or  indeed  valid  UTF-8 characters according to the later rules in RFC         or indeed valid UTF-8 characters according to the later  rules  in  RFC
401         3629.         3629.
402    
403    
404  THE ALTERNATIVE MATCHING FUNCTION  THE ALTERNATIVE MATCHING FUNCTION
405    
406         By  default,  pcretest  uses  the  standard  PCRE  matching   function,         By   default,  pcretest  uses  the  standard  PCRE  matching  function,
407         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
408         alternative matching function, pcre_dfa_test(),  which  operates  in  a         alternative  matching  function,  pcre_dfa_test(),  which operates in a
409         different  way,  and has some restrictions. The differences between the         different way, and has some restrictions. The differences  between  the
410         two functions are described in the pcrematching documentation.         two functions are described in the pcrematching documentation.
411    
412         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
413         contains  the -dfa option, the alternative matching function is called.         contains the -dfa option, the alternative matching function is  called.
414         This function finds all possible matches at a given point. If, however,         This function finds all possible matches at a given point. If, however,
415         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
416         first match is found. This is always the shortest possible match.         first match is found. This is always the shortest possible match.
417    
418    
419  DEFAULT OUTPUT FROM PCRETEST  DEFAULT OUTPUT FROM PCRETEST
420    
421         This section describes the output when the  normal  matching  function,         This  section  describes  the output when the normal matching function,
422         pcre_exec(), is being used.         pcre_exec(), is being used.
423    
424         When a match succeeds, pcretest outputs the list of captured substrings         When a match succeeds, pcretest outputs the list of captured substrings
425         that pcre_exec() returns, starting with number 0 for  the  string  that         that  pcre_exec()  returns,  starting with number 0 for the string that
426         matched  the  whole  pattern. Otherwise, it outputs "No match" when the         matched the whole pattern. Otherwise, it outputs "No  match"  when  the
427         return is PCRE_ERROR_NOMATCH, and "Partial match:" followed by the par-         return is PCRE_ERROR_NOMATCH, and "Partial match:" followed by the par-
428         tially  matching substring when pcre_exec() returns PCRE_ERROR_PARTIAL.         tially matching substring when pcre_exec() returns  PCRE_ERROR_PARTIAL.
429         For any other returns, it outputs the PCRE negative error number.  Here         For  any other returns, it outputs the PCRE negative error number. Here
430         is an example of an interactive pcretest run.         is an example of an interactive pcretest run.
431    
432           $ pcretest           $ pcretest
# Line 433  DEFAULT OUTPUT FROM PCRETEST Line 439  DEFAULT OUTPUT FROM PCRETEST
439           data> xyz           data> xyz
440           No match           No match
441    
442         Note  that unset capturing substrings that are not followed by one that         Note that unset capturing substrings that are not followed by one  that
443         is set are not returned by pcre_exec(), and are not shown by  pcretest.         is  set are not returned by pcre_exec(), and are not shown by pcretest.
444         In  the following example, there are two capturing substrings, but when         In the following example, there are two capturing substrings, but  when
445         the first data line is matched, the  second,  unset  substring  is  not         the  first  data  line  is  matched, the second, unset substring is not
446         shown.  An "internal" unset substring is shown as "<unset>", as for the         shown. An "internal" unset substring is shown as "<unset>", as for  the
447         second data line.         second data line.
448    
449             re> /(a)|(b)/             re> /(a)|(b)/
# Line 449  DEFAULT OUTPUT FROM PCRETEST Line 455  DEFAULT OUTPUT FROM PCRETEST
455            1: <unset>            1: <unset>
456            2: b            2: b
457    
458         If the strings contain any non-printing characters, they are output  as         If  the strings contain any non-printing characters, they are output as
459         \0x  escapes,  or  as \x{...} escapes if the /8 modifier was present on         \0x escapes, or as \x{...} escapes if the /8 modifier  was  present  on
460         the pattern. See below for the definition of  non-printing  characters.         the  pattern.  See below for the definition of non-printing characters.
461         If  the pattern has the /+ modifier, the output for substring 0 is fol-         If the pattern has the /+ modifier, the output for substring 0 is  fol-
462         lowed by the the rest of the subject string, identified  by  "0+"  like         lowed  by  the  the rest of the subject string, identified by "0+" like
463         this:         this:
464    
465             re> /cat/+             re> /cat/+
# Line 461  DEFAULT OUTPUT FROM PCRETEST Line 467  DEFAULT OUTPUT FROM PCRETEST
467            0: cat            0: cat
468            0+ aract            0+ aract
469    
470         If  the  pattern  has  the /g or /G modifier, the results of successive         If the pattern has the /g or /G modifier,  the  results  of  successive
471         matching attempts are output in sequence, like this:         matching attempts are output in sequence, like this:
472    
473             re> /\Bi(\w\w)/g             re> /\Bi(\w\w)/g
# Line 475  DEFAULT OUTPUT FROM PCRETEST Line 481  DEFAULT OUTPUT FROM PCRETEST
481    
482         "No match" is output only if the first match attempt fails.         "No match" is output only if the first match attempt fails.
483    
484         If any of the sequences \C, \G, or \L are present in a data  line  that         If  any  of the sequences \C, \G, or \L are present in a data line that
485         is  successfully  matched,  the substrings extracted by the convenience         is successfully matched, the substrings extracted  by  the  convenience
486         functions are output with C, G, or L after the string number instead of         functions are output with C, G, or L after the string number instead of
487         a colon. This is in addition to the normal full list. The string length         a colon. This is in addition to the normal full list. The string length
488         (that is, the return from the extraction function) is given  in  paren-         (that  is,  the return from the extraction function) is given in paren-
489         theses after each string for \C and \G.         theses after each string for \C and \G.
490    
491         Note that whereas patterns can be continued over several lines (a plain         Note that whereas patterns can be continued over several lines (a plain
492         ">" prompt is used for continuations), data lines may not. However new-         ">" prompt is used for continuations), data lines may not. However new-
493         lines  can  be included in data by means of the \n escape (or \r, \r\n,         lines can be included in data by means of the \n escape (or  \r,  \r\n,
494         etc., depending on the newline sequence setting).         etc., depending on the newline sequence setting).
495    
496    
497  OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION  OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION
498    
499         When the alternative matching function, pcre_dfa_exec(),  is  used  (by         When  the  alternative  matching function, pcre_dfa_exec(), is used (by
500         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
501         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
502         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:
503    
504             re> /(tang|tangerine|tan)/             re> /(tang|tangerine|tan)/
# Line 501  OUTPUT FROM THE ALTERNATIVE MATCHING FUN Line 507  OUTPUT FROM THE ALTERNATIVE MATCHING FUN
507            1: tang            1: tang
508            2: tan            2: tan
509    
510         (Using  the  normal  matching function on this data finds only "tang".)         (Using the normal matching function on this data  finds  only  "tang".)
511         The longest matching string is always given first (and numbered  zero).         The  longest matching string is always given first (and numbered zero).
512         After a PCRE_ERROR_PARTIAL return, the output is "Partial match:", fol-         After a PCRE_ERROR_PARTIAL return, the output is "Partial match:", fol-
513         lowed by the partially matching substring.         lowed by the partially matching substring.
514    
# Line 518  OUTPUT FROM THE ALTERNATIVE MATCHING FUN Line 524  OUTPUT FROM THE ALTERNATIVE MATCHING FUN
524            1: tan            1: tan
525            0: tan            0: tan
526    
527         Since  the  matching  function  does not support substring capture, the         Since the matching function does not  support  substring  capture,  the
528         escape sequences that are concerned with captured  substrings  are  not         escape  sequences  that  are concerned with captured substrings are not
529         relevant.         relevant.
530    
531    
532  RESTARTING AFTER A PARTIAL MATCH  RESTARTING AFTER A PARTIAL MATCH
533    
534         When the alternative matching function has given the PCRE_ERROR_PARTIAL         When the alternative matching function has given the PCRE_ERROR_PARTIAL
535         return, indicating that the subject partially matched the pattern,  you         return,  indicating that the subject partially matched the pattern, you
536         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
537         escape sequence. For example:         escape sequence. For example:
538    
539             re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/             re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
# Line 536  RESTARTING AFTER A PARTIAL MATCH Line 542  RESTARTING AFTER A PARTIAL MATCH
542           data> n05\R\D           data> n05\R\D
543            0: n05            0: n05
544    
545         For further information about partial  matching,  see  the  pcrepartial         For  further  information  about  partial matching, see the pcrepartial
546         documentation.         documentation.
547    
548    
549  CALLOUTS  CALLOUTS
550    
551         If  the pattern contains any callout requests, pcretest's callout func-         If the pattern contains any callout requests, pcretest's callout  func-
552         tion is called during matching. This works  with  both  matching  func-         tion  is  called  during  matching. This works with both matching func-
553         tions. By default, the called function displays the callout number, the         tions. By default, the called function displays the callout number, the
554         start and current positions in the text at the callout  time,  and  the         start  and  current  positions in the text at the callout time, and the
555         next pattern item to be tested. For example, the output         next pattern item to be tested. For example, the output
556    
557           --->pqrabcdef           --->pqrabcdef
558             0    ^  ^     \d             0    ^  ^     \d
559    
560         indicates  that  callout number 0 occurred for a match attempt starting         indicates that callout number 0 occurred for a match  attempt  starting
561         at the fourth character of the subject string, when the pointer was  at         at  the fourth character of the subject string, when the pointer was at
562         the  seventh  character of the data, and when the next pattern item was         the seventh character of the data, and when the next pattern  item  was
563         \d. Just one circumflex is output if the start  and  current  positions         \d.  Just  one  circumflex is output if the start and current positions
564         are the same.         are the same.
565    
566         Callouts numbered 255 are assumed to be automatic callouts, inserted as         Callouts numbered 255 are assumed to be automatic callouts, inserted as
567         a result of the /C pattern modifier. In this case, instead  of  showing         a  result  of the /C pattern modifier. In this case, instead of showing
568         the  callout  number, the offset in the pattern, preceded by a plus, is         the callout number, the offset in the pattern, preceded by a  plus,  is
569         output. For example:         output. For example:
570    
571             re> /\d?[A-E]\*/C             re> /\d?[A-E]\*/C
# Line 571  CALLOUTS Line 577  CALLOUTS
577           +10 ^ ^           +10 ^ ^
578            0: E*            0: E*
579    
580         The callout function in pcretest returns zero (carry  on  matching)  by         The  callout  function  in pcretest returns zero (carry on matching) by
581         default,  but you can use a \C item in a data line (as described above)         default, but you can use a \C item in a data line (as described  above)
582         to change this.         to change this.
583    
584         Inserting callouts can be helpful when using pcretest to check  compli-         Inserting  callouts can be helpful when using pcretest to check compli-
585         cated  regular expressions. For further information about callouts, see         cated regular expressions. For further information about callouts,  see
586         the pcrecallout documentation.         the pcrecallout documentation.
587    
588    
589  NON-PRINTING CHARACTERS  NON-PRINTING CHARACTERS
590    
591         When pcretest is outputting text in the compiled version of a  pattern,         When  pcretest is outputting text in the compiled version of a pattern,
592         bytes  other  than 32-126 are always treated as non-printing characters         bytes other than 32-126 are always treated as  non-printing  characters
593         are are therefore shown as hex escapes.         are are therefore shown as hex escapes.
594    
595         When pcretest is outputting text that is a matched part  of  a  subject         When  pcretest  is  outputting text that is a matched part of a subject
596         string,  it behaves in the same way, unless a different locale has been         string, it behaves in the same way, unless a different locale has  been
597         set for the  pattern  (using  the  /L  modifier).  In  this  case,  the         set  for  the  pattern  (using  the  /L  modifier).  In  this case, the
598         isprint() function to distinguish printing and non-printing characters.         isprint() function to distinguish printing and non-printing characters.
599    
600    
601  SAVING AND RELOADING COMPILED PATTERNS  SAVING AND RELOADING COMPILED PATTERNS
602    
603         The  facilities  described  in  this section are not available when the         The facilities described in this section are  not  available  when  the
604         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-
605         ifier is specified.         ifier is specified.
606    
607         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
608         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
609         file name.  For example:         file name.  For example:
610    
611           /pattern/im >/some/file           /pattern/im >/some/file
612    
613         See  the pcreprecompile documentation for a discussion about saving and         See the pcreprecompile documentation for a discussion about saving  and
614         re-using compiled patterns.         re-using compiled patterns.
615    
616         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
617         length  of  the  compiled  pattern  data  followed by the length of the         length of the compiled pattern data  followed  by  the  length  of  the
618         optional study data, each written as four  bytes  in  big-endian  order         optional  study  data,  each  written as four bytes in big-endian order
619         (most  significant  byte  first). If there is no study data (either the         (most significant byte first). If there is no study  data  (either  the
620         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-
621         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
622         compiled pattern. If there is additional study data, this follows imme-         compiled pattern. If there is additional study data, this follows imme-
623         diately  after  the  compiled pattern. After writing the file, pcretest         diately after the compiled pattern. After writing  the  file,  pcretest
624         expects to read a new pattern.         expects to read a new pattern.
625    
626         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
627         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  <
628         character, as otherwise pcretest will interpret the line as  a  pattern         character,  as  otherwise pcretest will interpret the line as a pattern
629         delimited by < characters.  For example:         delimited by < characters.  For example:
630    
631            re> </some/file            re> </some/file
632           Compiled regex loaded from /some/file           Compiled regex loaded from /some/file
633           No study data           No study data
634    
635         When  the pattern has been loaded, pcretest proceeds to read data lines         When the pattern has been loaded, pcretest proceeds to read data  lines
636         in the usual way.         in the usual way.
637    
638         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
639         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
640         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
641         machine and run on a SPARC machine.         machine and run on a SPARC machine.
642    
643         File  names  for  saving and reloading can be absolute or relative, but         File names for saving and reloading can be absolute  or  relative,  but
644         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
645         a tilde (~) is not available.         a tilde (~) is not available.
646    
647         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-
648         ing and experimentation. It is not intended for production use  because         ing  and experimentation. It is not intended for production use because
649         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
650         no facility for supplying  custom  character  tables  for  use  with  a         no  facility  for  supplying  custom  character  tables  for use with a
651         reloaded  pattern.  If  the  original  pattern was compiled with custom         reloaded pattern. If the original  pattern  was  compiled  with  custom
652         tables, an attempt to match a subject string using a  reloaded  pattern         tables,  an  attempt to match a subject string using a reloaded pattern
653         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
654         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.
655    
656    
657  SEE ALSO  SEE ALSO
658    
659         pcre(3), pcreapi(3), pcrecallout(3),  pcrematching(3),  pcrepartial(d),         pcre(3),  pcreapi(3),  pcrecallout(3), pcrematching(3), pcrepartial(d),
660         pcrepattern(3), pcreprecompile(3).         pcrepattern(3), pcreprecompile(3).
661    
662    
# Line 663  AUTHOR Line 669  AUTHOR
669    
670  REVISION  REVISION
671    
672         Last updated: 26 September 2009         Last updated: 12 May 2010
673         Copyright (c) 1997-2009 University of Cambridge.         Copyright (c) 1997-2010 University of Cambridge.

Legend:
Removed from v.461  
changed lines
  Added in v.518

  ViewVC Help
Powered by ViewVC 1.1.5