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revision 77 by nigel, Sat Feb 24 21:40:45 2007 UTC revision 784 by ph10, Mon Dec 5 12:33:44 2011 UTC
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1  PCRETEST(1)                                                        PCRETEST(1)  PCRETEST(1)                                                        PCRETEST(1)
2    
3    
   
4  NAME  NAME
5         pcretest - a program for testing Perl-compatible regular expressions.         pcretest - a program for testing Perl-compatible regular expressions.
6    
7    
8  SYNOPSIS  SYNOPSIS
9    
10         pcretest [-C] [-d] [-dfa] [-i] [-m] [-o osize] [-p] [-t] [source]         pcretest [options] [input file [output file]]
             [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
14         expressions.  This document describes the features of the test program;         expressions.  This document describes the features of the test program;
15         for details of the regular expressions themselves, see the  pcrepattern         for details of the regular expressions themselves, see the  pcrepattern
16         documentation. For details of the PCRE library function calls and their         documentation. For details of the PCRE library function calls and their
17         options, see the pcreapi documentation.         options, see the pcreapi documentation. The input  for  pcretest  is  a
18           sequence  of  regular expression patterns and strings to be matched, as
19           described below. The output shows the result of each match. Options  on
20           the command line and the patterns control PCRE options and exactly what
21           is output.
22    
23    
24  OPTIONS  COMMAND LINE OPTIONS
25    
26           -b        Behave as if each pattern has the /B (show byte  code)  modi-
27                     fier; the internal form is output after compilation.
28    
29         -C        Output the version number of the PCRE library, and all avail-         -C        Output the version number of the PCRE library, and all avail-
30                   able   information  about  the  optional  features  that  are                   able  information  about  the  optional  features  that   are
31                   included, and then exit.                   included, and then exit.
32    
33         -d        Behave as if each regex has  the  /D  (debug)  modifier;  the         -d        Behave  as  if  each pattern has the /D (debug) modifier; the
34                   internal form is output after compilation.                   internal form and information about the compiled  pattern  is
35                     output after compilation; -d is equivalent to -b -i.
36    
37         -dfa      Behave  as if each data line contains the \D escape sequence;         -dfa      Behave  as if each data line contains the \D escape sequence;
38                   this    causes    the    alternative    matching    function,                   this    causes    the    alternative    matching    function,
39                   pcre_dfa_exec(),   to   be   used  instead  of  the  standard                   pcre_dfa_exec(),   to   be   used  instead  of  the  standard
40                   pcre_exec() function (more detail is given below).                   pcre_exec() function (more detail is given below).
41    
42         -i        Behave as if each regex  has  the  /I  modifier;  information         -help     Output a brief summary these options and then exit.
43    
44           -i        Behave as if each pattern has the  /I  modifier;  information
45                   about the compiled pattern is given after compilation.                   about the compiled pattern is given after compilation.
46    
47         -m        Output  the  size  of each compiled pattern after it has been         -M        Behave  as if each data line contains the \M escape sequence;
48                   compiled. This is equivalent to adding  /M  to  each  regular                   this causes PCRE to  discover  the  minimum  MATCH_LIMIT  and
49                   expression.   For  compatibility  with  earlier  versions  of                   MATCH_LIMIT_RECURSION settings by calling pcre_exec() repeat-
50                   pcretest, -s is a synonym for -m.                   edly with different limits.
51    
52           -m        Output the size of each compiled pattern after  it  has  been
53                     compiled.  This  is  equivalent  to adding /M to each regular
54                     expression.
55    
56         -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
57                   when  calling  pcre_exec()  to be osize. The default value is                   when  calling pcre_exec() or pcre_dfa_exec() to be osize. The
58                   45, which is enough for 14 capturing subexpressions. The vec-                   default value is 45, which is enough for 14 capturing  subex-
59                   tor  size  can  be  changed  for individual matching calls by                   pressions   for  pcre_exec()  or  22  different  matches  for
60                   including \O in the data line (see below).                   pcre_dfa_exec(). The vector size can be changed for  individ-
61                     ual  matching  calls  by  including  \O in the data line (see
62         -p        Behave as if each regex has the /P modifier; the POSIX  wrap-                   below).
63                   per  API  is used to call PCRE. None of the other options has  
64                   any effect when -p is set.         -p        Behave as if each pattern has  the  /P  modifier;  the  POSIX
65                     wrapper  API  is used to call PCRE. None of the other options
66                     has any effect when -p is set.
67    
68           -q        Do not output the version number of pcretest at the start  of
69                     execution.
70    
71           -S size   On  Unix-like  systems, set the size of the run-time stack to
72                     size megabytes.
73    
74           -s or -s+ Behave as if each pattern  has  the  /S  modifier;  in  other
75                     words,  force each pattern to be studied. If -s+ is used, the
76                     PCRE_STUDY_JIT_COMPILE flag is passed to pcre_study(),  caus-
77                     ing  just-in-time  optimization  to be set up if it is avail-
78                     able. If the  /I  or  /D  option  is  present  on  a  pattern
79                     (requesting  output  about the compiled pattern), information
80                     about the result of studying is not included when studying is
81                     caused  only  by  -s  and neither -i nor -d is present on the
82                     command line. This behaviour means that the output from tests
83                     that  are run with and without -s should be identical, except
84                     when options that output information about the actual running
85                     of  a  match are set. The -M, -t, and -tm options, which give
86                     information about resources used, are likely to produce  dif-
87                     ferent  output with and without -s. Output may also differ if
88                     the /C option is present on an individual pattern. This  uses
89                     callouts  to  trace the the matching process, and this may be
90                     different between studied and non-studied  patterns.  If  the
91                     pattern contains (*MARK) items there may also be differences,
92                     for the same reason. The -s command line option can be  over-
93                     ridden  for  specific  patterns  that should never be studied
94                     (see the /S pattern modifier below).
95    
96         -t        Run each compile, study, and match many times with  a  timer,         -t        Run each compile, study, and match many times with  a  timer,
97                   and  output resulting time per compile or match (in millisec-                   and  output resulting time per compile or match (in millisec-
98                   onds). Do not set -m with -t, because you will then  get  the                   onds). Do not set -m with -t, because you will then  get  the
99                   size  output  a  zillion  times,  and the timing will be dis-                   size  output  a  zillion  times,  and the timing will be dis-
100                   torted.                   torted. You can control the number  of  iterations  that  are
101                     used  for timing by following -t with a number (as a separate
102                     item on the command line). For example, "-t 1000" would iter-
103                     ate 1000 times. The default is to iterate 500000 times.
104    
105           -tm       This is like -t except that it times only the matching phase,
106                     not the compile or study phases.
107    
108    
109  DESCRIPTION  DESCRIPTION
# Line 66  DESCRIPTION Line 115  DESCRIPTION
115         "re>" to prompt for regular expressions, and "data>" to prompt for data         "re>" to prompt for regular expressions, and "data>" to prompt for data
116         lines.         lines.
117    
118           When  pcretest  is  built,  a  configuration option can specify that it
119           should be linked with the libreadline library. When this  is  done,  if
120           the input is from a terminal, it is read using the readline() function.
121           This provides line-editing and history facilities. The output from  the
122           -help option states whether or not readline() will be used.
123    
124         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.
125         Each set starts with a regular expression, and continues with any  num-         Each set starts with a regular expression, and continues with any  num-
126         ber of data lines to be matched against the pattern.         ber of data lines to be matched against the pattern.
127    
128         Each  data line is matched separately and independently. If you want to         Each  data line is matched separately and independently. If you want to
129         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
130         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
131         length of data line is 30,000 characters.         to encode the newline sequences. There is no limit  on  the  length  of
132           data  lines;  the  input  buffer is automatically extended if it is too
133           small.
134    
135         An empty line signals the end of the data lines, at which point  a  new         An empty line signals the end of the data lines, at which point  a  new
136         regular  expression is read. The regular expressions are given enclosed         regular  expression is read. The regular expressions are given enclosed
137         in any non-alphanumeric delimiters other than backslash, for example         in any non-alphanumeric delimiters other than backslash, for example:
138    
139           /(a|bc)x+yz/           /(a|bc)x+yz/
140    
# Line 112  PATTERN MODIFIERS Line 169  PATTERN MODIFIERS
169         single  characters.  Following  Perl usage, these are referred to below         single  characters.  Following  Perl usage, these are referred to below
170         as, for example, "the /i modifier", even though the  delimiter  of  the         as, for example, "the /i modifier", even though the  delimiter  of  the
171         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
172         modifiers. Whitespace may appear between the  final  pattern  delimiter         modifiers. White space may appear between the final  pattern  delimiter
173         and the first modifier, and between the modifiers themselves.         and the first modifier, and between the modifiers themselves.
174    
175         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,
# Line 122  PATTERN MODIFIERS Line 179  PATTERN MODIFIERS
179    
180           /caseless/i           /caseless/i
181    
182         The following table shows additional modifiers for setting PCRE options         The following table shows additional modifiers for  setting  PCRE  com-
183         that do not correspond to anything in Perl:         pile-time options that do not correspond to anything in Perl:
184    
185             /8              PCRE_UTF8
186             /?              PCRE_NO_UTF8_CHECK
187             /A              PCRE_ANCHORED
188             /C              PCRE_AUTO_CALLOUT
189             /E              PCRE_DOLLAR_ENDONLY
190             /f              PCRE_FIRSTLINE
191             /J              PCRE_DUPNAMES
192             /N              PCRE_NO_AUTO_CAPTURE
193             /U              PCRE_UNGREEDY
194             /W              PCRE_UCP
195             /X              PCRE_EXTRA
196             /Y              PCRE_NO_START_OPTIMIZE
197             /<JS>           PCRE_JAVASCRIPT_COMPAT
198             /<cr>           PCRE_NEWLINE_CR
199             /<lf>           PCRE_NEWLINE_LF
200             /<crlf>         PCRE_NEWLINE_CRLF
201             /<anycrlf>      PCRE_NEWLINE_ANYCRLF
202             /<any>          PCRE_NEWLINE_ANY
203             /<bsr_anycrlf>  PCRE_BSR_ANYCRLF
204             /<bsr_unicode>  PCRE_BSR_UNICODE
205    
206           The  modifiers  that are enclosed in angle brackets are literal strings
207           as shown, including the angle brackets, but the letters within  can  be
208           in  either case.  This example sets multiline matching with CRLF as the
209           line ending sequence:
210    
211             /^abc/m<CRLF>
212    
213           As well as turning on the PCRE_UTF8 option, the /8 modifier also causes
214           any  non-printing  characters in output strings to be printed using the
215           \x{hh...} notation if they are valid UTF-8 sequences. Full  details  of
216           the PCRE options are given in the pcreapi documentation.
217    
218           /A    PCRE_ANCHORED     Finding all matches in a string
          /C    PCRE_AUTO_CALLOUT  
          /E    PCRE_DOLLAR_ENDONLY  
          /f    PCRE_FIRSTLINE  
          /N    PCRE_NO_AUTO_CAPTURE  
          /U    PCRE_UNGREEDY  
          /X    PCRE_EXTRA  
219    
220         Searching  for  all  possible matches within each subject string can be         Searching  for  all  possible matches within each subject string can be
221         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 144  PATTERN MODIFIERS Line 228  PATTERN MODIFIERS
228         or \B).         or \B).
229    
230         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
231         string, the next call is done with the PCRE_NOTEMPTY and  PCRE_ANCHORED         string, the next  call  is  done  with  the  PCRE_NOTEMPTY_ATSTART  and
232         flags  set in order to search for another, non-empty, match at the same         PCRE_ANCHORED  flags  set  in  order  to search for another, non-empty,
233         point.  If this second match fails, the start  offset  is  advanced  by         match at the same point. If this second match fails, the  start  offset
234         one,  and  the normal match is retried. This imitates the way Perl han-         is  advanced,  and  the  normal match is retried. This imitates the way
235         dles such cases when using the /g modifier or the split() function.         Perl handles such cases when using the /g modifier or the split() func-
236           tion.  Normally,  the start offset is advanced by one character, but if
237           the newline convention recognizes CRLF as a newline,  and  the  current
238           character is CR followed by LF, an advance of two is used.
239    
240       Other modifiers
241    
242         There are yet more modifiers for controlling the way pcretest operates.         There are yet more modifiers for controlling the way pcretest operates.
243    
244         The  /+ modifier requests that as well as outputting the substring that         The  /+ modifier requests that as well as outputting the substring that
245         matched the entire pattern, pcretest  should  in  addition  output  the         matched the entire pattern, pcretest  should  in  addition  output  the
246         remainder  of  the  subject  string. This is useful for tests where the         remainder  of  the  subject  string. This is useful for tests where the
247         subject contains multiple copies of the same substring.         subject contains multiple copies of the same substring. If the +  modi-
248           fier  appears  twice, the same action is taken for captured substrings.
249           In each case the remainder is output on the following line with a  plus
250           character  following  the  capture number. Note that this modifier must
251           not immediately follow the /S modifier because /S+ has another meaning.
252    
253           The /= modifier requests that the  values  of  all  potential  captured
254           parentheses  be  output  after a match by pcre_exec(). By default, only
255           those up to the highest one actually used in the match are output (cor-
256           responding  to the return code from pcre_exec()). Values in the offsets
257           vector corresponding to higher numbers should be set to -1,  and  these
258           are  output  as  "<unset>".  This modifier gives a way of checking that
259           this is happening.
260    
261           The /B modifier is a debugging feature. It requests that pcretest  out-
262           put  a representation of the compiled byte code after compilation. Nor-
263           mally this information contains length and offset values;  however,  if
264           /Z  is also present, this data is replaced by spaces. This is a special
265           feature for use in the automatic test scripts; it ensures that the same
266           output is generated for different internal link sizes.
267    
268         The /L modifier must be followed directly by the name of a locale,  for         The  /D modifier is a PCRE debugging feature, and is equivalent to /BI,
269         example,         that is, both the /B and the /I modifiers.
270    
271           /pattern/Lfr_FR         The /F modifier causes pcretest to flip the byte order of the fields in
272           the  compiled  pattern  that  contain  2-byte  and 4-byte numbers. This
273         For this reason, it must be the last modifier. The given locale is set,         facility is for testing the feature in PCRE that allows it  to  execute
274         pcre_maketables() is called to build a set of character tables for  the         patterns that were compiled on a host with a different endianness. This
275         locale,  and  this  is then passed to pcre_compile() when compiling the         feature is not available when the POSIX  interface  to  PCRE  is  being
276         regular expression. Without an /L  modifier,  NULL  is  passed  as  the         used,  that is, when the /P pattern modifier is specified. See also the
277         tables  pointer; that is, /L applies only to the expression on which it         section about saving and reloading compiled patterns below.
        appears.  
278    
279         The /I modifier requests that pcretest  output  information  about  the         The /I modifier requests that pcretest  output  information  about  the
280         compiled  pattern (whether it is anchored, has a fixed first character,         compiled  pattern (whether it is anchored, has a fixed first character,
# Line 175  PATTERN MODIFIERS Line 282  PATTERN MODIFIERS
282         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-
283         put.         put.
284    
285         The /D modifier is a PCRE debugging feature, which also assumes /I.  It         The /K modifier requests pcretest to show names from backtracking  con-
286         causes  the  internal form of compiled regular expressions to be output         trol  verbs  that  are  returned  from  calls to pcre_exec(). It causes
287         after compilation. If the pattern was studied, the information returned         pcretest to create a pcre_extra block if one has not already been  cre-
288         is also output.         ated by a call to pcre_study(), and to set the PCRE_EXTRA_MARK flag and
289           the mark field within it, every time that pcre_exec() is called. If the
290           variable  that  the  mark field points to is non-NULL for a match, non-
291           match, or partial match, pcretest prints the string to which it points.
292           For a match, this is shown on a line by itself, tagged with "MK:".  For
293           a non-match it is added to the message.
294    
295         The /F modifier causes pcretest to flip the byte order of the fields in         The /L modifier must be followed directly by the name of a locale,  for
296         the compiled pattern that  contain  2-byte  and  4-byte  numbers.  This         example,
297         facility  is  for testing the feature in PCRE that allows it to execute  
298         patterns that were compiled on a host with a different endianness. This           /pattern/Lfr_FR
299         feature  is  not  available  when  the POSIX interface to PCRE is being  
300         used, that is, when the /P pattern modifier is specified. See also  the         For this reason, it must be the last modifier. The given locale is set,
301         section about saving and reloading compiled patterns below.         pcre_maketables() is called to build a set of character tables for  the
302           locale,  and  this  is then passed to pcre_compile() when compiling the
303           regular expression. Without an /L (or /T) modifier, NULL is  passed  as
304           the tables pointer; that is, /L applies only to the expression on which
305           it appears.
306    
307           The /M modifier causes the size of memory block used to hold  the  com-
308           piled  pattern to be output. This does not include the size of the pcre
309           block; it is just the actual compiled data. If the pattern is  success-
310           fully  studied  with the PCRE_STUDY_JIT_COMPILE option, the size of the
311           JIT compiled code is also output.
312    
313           If the /S modifier appears once, it causes pcre_study()  to  be  called
314           after  the  expression has been compiled, and the results used when the
315           expression is matched. If /S appears  twice,  it  suppresses  studying,
316           even if it was requested externally by the -s command line option. This
317           makes it possible to specify that certain patterns are always  studied,
318           and others are never studied, independently of -s. This feature is used
319           in the test files in a few cases where the output is different when the
320           pattern is studied.
321    
322           If  the  /S modifier is immediately followed by a + character, the call
323           to  pcre_study()  is  made  with  the  PCRE_STUDY_JIT_COMPILE   option,
324           requesting  just-in-time  optimization support if it is available. Note
325           that there is also a /+ modifier; it  must  not  be  given  immediately
326           after  /S  because this will be misinterpreted. If JIT studying is suc-
327           cessful, it will automatically be used when pcre_exec() is run,  except
328           when  incompatible  run-time  options  are specified. These include the
329           partial matching options; a complete list is given in the pcrejit docu-
330           mentation.  See  also the \J escape sequence below for a way of setting
331           the size of the JIT stack.
332    
333           The /T modifier must be followed by a single digit. It  causes  a  spe-
334           cific  set of built-in character tables to be passed to pcre_compile().
335           It is used in the standard PCRE tests to check behaviour with different
336           character tables. The digit specifies the tables as follows:
337    
338             0   the default ASCII tables, as distributed in
339                   pcre_chartables.c.dist
340             1   a set of tables defining ISO 8859 characters
341    
342         The  /S  modifier causes pcre_study() to be called after the expression         In  table 1, some characters whose codes are greater than 128 are iden-
343         has been compiled, and the results used when the expression is matched.         tified as letters, digits, spaces, etc.
344    
345         The  /M  modifier causes the size of memory block used to hold the com-     Using the POSIX wrapper API
        piled pattern to be output.  
346    
347         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
348         rather  than  its  native  API.  When this is done, all other modifiers         rather than its native API. When /P is set, the following modifiers set
349         except /i, /m, and /+ are ignored. REG_ICASE is set if /i  is  present,         options for the regcomp() function:
350         and  REG_NEWLINE  is  set if /m is present. The wrapper functions force  
351         PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless REG_NEWLINE is  set.           /i    REG_ICASE
352             /m    REG_NEWLINE
353         The  /8 modifier causes pcretest to call PCRE with the PCRE_UTF8 option           /N    REG_NOSUB
354         set. This turns on support for UTF-8 character handling in  PCRE,  pro-           /s    REG_DOTALL     )
355         vided  that  it  was  compiled with this support enabled. This modifier           /U    REG_UNGREEDY   ) These options are not part of
356         also causes any non-printing characters in output strings to be printed           /W    REG_UCP        )   the POSIX standard
357         using the \x{hh...} notation if they are valid UTF-8 sequences.           /8    REG_UTF8       )
358    
359         If  the  /?  modifier  is  used  with  /8,  it  causes pcretest to call         The /+ modifier works as  described  above.  All  other  modifiers  are
360         pcre_compile() with the  PCRE_NO_UTF8_CHECK  option,  to  suppress  the         ignored.
        checking of the string for UTF-8 validity.  
361    
362    
363  DATA LINES  DATA LINES
364    
365         Before  each  data  line is passed to pcre_exec(), leading and trailing         Before  each  data  line is passed to pcre_exec(), leading and trailing
366         whitespace is removed, and it is then scanned for \  escapes.  Some  of         white space is removed, and it is then scanned for \ escapes.  Some  of
367         these  are  pretty esoteric features, intended for checking out some of         these  are  pretty esoteric features, intended for checking out some of
368         the more complicated features of PCRE. If you are just  testing  "ordi-         the more complicated features of PCRE. If you are just  testing  "ordi-
369         nary"  regular  expressions,  you probably don't need any of these. The         nary"  regular  expressions,  you probably don't need any of these. The
370         following escapes are recognized:         following escapes are recognized:
371    
372           \a         alarm (= BEL)           \a         alarm (BEL, \x07)
373           \b         backspace           \b         backspace (\x08)
374           \e         escape           \e         escape (\x27)
375           \f         formfeed           \f         form feed (\x0c)
376           \n         newline           \n         newline (\x0a)
377           \r         carriage return           \qdd       set the PCRE_MATCH_LIMIT limit to dd
378           \t         tab                        (any number of digits)
379           \v         vertical tab           \r         carriage return (\x0d)
380             \t         tab (\x09)
381             \v         vertical tab (\x0b)
382           \nnn       octal character (up to 3 octal digits)           \nnn       octal character (up to 3 octal digits)
383           \xhh       hexadecimal character (up to 2 hex digits)                        always a byte unless > 255 in UTF-8 mode
384             \xhh       hexadecimal byte (up to 2 hex digits)
385           \x{hh...}  hexadecimal character, any number of digits           \x{hh...}  hexadecimal character, any number of digits
386                        in UTF-8 mode                        in UTF-8 mode
387           \A         pass the PCRE_ANCHORED option to pcre_exec()           \A         pass the PCRE_ANCHORED option to pcre_exec()
388                          or pcre_dfa_exec()
389           \B         pass the PCRE_NOTBOL option to pcre_exec()           \B         pass the PCRE_NOTBOL option to pcre_exec()
390                          or pcre_dfa_exec()
391           \Cdd       call pcre_copy_substring() for substring dd           \Cdd       call pcre_copy_substring() for substring dd
392                        after a successful match (number less than 32)                        after a successful match (number less than 32)
393           \Cname     call pcre_copy_named_substring() for substring           \Cname     call pcre_copy_named_substring() for substring
# Line 255  DATA LINES Line 409  DATA LINES
409           \Gname     call pcre_get_named_substring() for substring           \Gname     call pcre_get_named_substring() for substring
410                        "name" after a successful match (name termin-                        "name" after a successful match (name termin-
411                        ated by next non-alphanumeric character)                        ated by next non-alphanumeric character)
412             \Jdd       set up a JIT stack of dd kilobytes maximum (any
413                          number of digits)
414           \L         call pcre_get_substringlist() after a           \L         call pcre_get_substringlist() after a
415                        successful match                        successful match
416           \M         discover the minimum MATCH_LIMIT setting           \M         discover the minimum MATCH_LIMIT and
417                          MATCH_LIMIT_RECURSION settings
418           \N         pass the PCRE_NOTEMPTY option to pcre_exec()           \N         pass the PCRE_NOTEMPTY option to pcre_exec()
419                          or pcre_dfa_exec(); if used twice, pass the
420                          PCRE_NOTEMPTY_ATSTART option
421           \Odd       set the size of the output vector passed to           \Odd       set the size of the output vector passed to
422                        pcre_exec() to dd (any number of digits)                        pcre_exec() to dd (any number of digits)
423           \P         pass the PCRE_PARTIAL option to pcre_exec()           \P         pass the PCRE_PARTIAL_SOFT option to pcre_exec()
424                        or pcre_dfa_exec()                        or pcre_dfa_exec(); if used twice, pass the
425                          PCRE_PARTIAL_HARD option
426             \Qdd       set the PCRE_MATCH_LIMIT_RECURSION limit to dd
427                          (any number of digits)
428           \R         pass the PCRE_DFA_RESTART option to pcre_dfa_exec()           \R         pass the PCRE_DFA_RESTART option to pcre_dfa_exec()
429           \S         output details of memory get/free calls during matching           \S         output details of memory get/free calls during matching
430             \Y         pass the PCRE_NO_START_OPTIMIZE option to pcre_exec()
431                          or pcre_dfa_exec()
432           \Z         pass the PCRE_NOTEOL option to pcre_exec()           \Z         pass the PCRE_NOTEOL option to pcre_exec()
433                          or pcre_dfa_exec()
434           \?         pass the PCRE_NO_UTF8_CHECK option to           \?         pass the PCRE_NO_UTF8_CHECK option to
435                        pcre_exec()                        pcre_exec() or pcre_dfa_exec()
436           \>dd       start the match at offset dd (any number of digits);           \>dd       start the match at offset dd (optional "-"; then
437                        this sets the startoffset argument for pcre_exec()                        any number of digits); this sets the startoffset
438                          argument for pcre_exec() or pcre_dfa_exec()
439         A backslash followed by anything else just escapes the  anything  else.           \<cr>      pass the PCRE_NEWLINE_CR option to pcre_exec()
440         If  the very last character is a backslash, it is ignored. This gives a                        or pcre_dfa_exec()
441         way of passing an empty line as data, since a real  empty  line  termi-           \<lf>      pass the PCRE_NEWLINE_LF option to pcre_exec()
442                          or pcre_dfa_exec()
443             \<crlf>    pass the PCRE_NEWLINE_CRLF option to pcre_exec()
444                          or pcre_dfa_exec()
445             \<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to pcre_exec()
446                          or pcre_dfa_exec()
447             \<any>     pass the PCRE_NEWLINE_ANY option to pcre_exec()
448                          or pcre_dfa_exec()
449    
450           Note that \xhh always specifies one byte,  even  in  UTF-8  mode;  this
451           makes it possible to construct invalid UTF-8 sequences for testing pur-
452           poses. On the other hand, \x{hh} is interpreted as a UTF-8 character in
453           UTF-8  mode, generating more than one byte if the value is greater than
454           127. When not in UTF-8 mode, it generates one byte for values less than
455           256, and causes an error for greater values.
456    
457           The  escapes  that  specify  line ending sequences are literal strings,
458           exactly as shown. No more than one newline setting should be present in
459           any data line.
460    
461           A  backslash  followed by anything else just escapes the anything else.
462           If the very last character is a backslash, it is ignored. This gives  a
463           way  of  passing  an empty line as data, since a real empty line termi-
464         nates the data input.         nates the data input.
465    
466           The \J escape provides a way of setting the maximum stack size that  is
467           used  by the just-in-time optimization code. It is ignored if JIT opti-
468           mization is not being used. Providing a stack that is larger  than  the
469           default 32K is necessary only for very complicated patterns.
470    
471         If  \M  is present, pcretest calls pcre_exec() several times, with dif-         If  \M  is present, pcretest calls pcre_exec() several times, with dif-
472         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
473         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
474         to complete. This number is a measure of the amount  of  recursion  and         each parameter  that  allow  pcre_exec()  to  complete  without  error.
475         backtracking  that takes place, and checking it out can be instructive.         Because  this  is testing a specific feature of the normal interpretive
476         For most simple matches, the number is quite small,  but  for  patterns         pcre_exec() execution, the use of any JIT optimization that might  have
477         with  very large numbers of matching possibilities, it can become large         been set up by the /S+ qualifier of -s+ option is disabled.
478         very quickly with increasing length of subject string.  
479           The  match_limit number is a measure of the amount of backtracking that
480           takes place, and checking it out can be instructive.  For  most  simple
481           matches,  the  number  is quite small, but for patterns with very large
482           numbers of matching possibilities, it can  become  large  very  quickly
483           with  increasing  length  of  subject string. The match_limit_recursion
484           number is a measure of how much stack (or, if  PCRE  is  compiled  with
485           NO_RECURSE,  how  much  heap)  memory  is  needed to complete the match
486           attempt.
487    
488         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
489         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
490         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.
491    
492         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-
493         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
494         and REG_NOTEOL to be passed to regexec() respectively.         effect are \B,  \N,  and  \Z,  causing  REG_NOTBOL,  REG_NOTEMPTY,  and
495           REG_NOTEOL, respectively, to be passed to regexec().
496         The use of \x{hh...} to represent UTF-8 characters is not dependent  on  
497         the  use  of  the  /8 modifier on the pattern. It is recognized always.         The  use of \x{hh...} to represent UTF-8 characters is not dependent on
498         There may be any number of hexadecimal digits inside  the  braces.  The         the use of the /8 modifier on the pattern.  It  is  recognized  always.
499         result  is from one to six bytes, encoded according to the UTF-8 rules.         There  may  be  any number of hexadecimal digits inside the braces. The
500           result is from one to six bytes,  encoded  according  to  the  original
501           UTF-8  rules  of  RFC  2279.  This  allows for values in the range 0 to
502           0x7FFFFFFF. Note that not all of those are valid Unicode  code  points,
503           or  indeed  valid  UTF-8 characters according to the later rules in RFC
504           3629.
505    
506    
507  THE ALTERNATIVE MATCHING FUNCTION  THE ALTERNATIVE MATCHING FUNCTION
# Line 321  DEFAULT OUTPUT FROM PCRETEST Line 526  DEFAULT OUTPUT FROM PCRETEST
526    
527         When a match succeeds, pcretest outputs the list of captured substrings         When a match succeeds, pcretest outputs the list of captured substrings
528         that pcre_exec() returns, starting with number 0 for  the  string  that         that pcre_exec() returns, starting with number 0 for  the  string  that
529         matched the whole pattern. Otherwise, it outputs "No match" or "Partial         matched  the  whole  pattern. Otherwise, it outputs "No match" when the
530         match" when pcre_exec() returns PCRE_ERROR_NOMATCH  or  PCRE_ERROR_PAR-         return is PCRE_ERROR_NOMATCH, and "Partial match:" followed by the par-
531         TIAL,  respectively, and otherwise the PCRE negative error number. Here         tially  matching substring when pcre_exec() returns PCRE_ERROR_PARTIAL.
532         is an example of an interactive pcretest run.         (Note that this is the entire substring that was inspected  during  the
533           partial  match; it may include characters before the actual match start
534           if a lookbehind assertion, \K, \b, or \B was involved.) For  any  other
535           return,  pcretest  outputs  the  PCRE negative error number and a short
536           descriptive phrase. If the error is a failed UTF-8  string  check,  the
537           byte  offset  of the start of the failing character and the reason code
538           are also output, provided that the size of  the  output  vector  is  at
539           least two. Here is an example of an interactive pcretest run.
540    
541           $ pcretest           $ pcretest
542           PCRE version 5.00 07-Sep-2004           PCRE version 8.13 2011-04-30
543    
544             re> /^abc(\d+)/             re> /^abc(\d+)/
545           data> abc123           data> abc123
# Line 336  DEFAULT OUTPUT FROM PCRETEST Line 548  DEFAULT OUTPUT FROM PCRETEST
548           data> xyz           data> xyz
549           No match           No match
550    
551           Unset capturing substrings that are not followed by one that is set are
552           not returned by pcre_exec(), and are not shown by pcretest. In the fol-
553           lowing  example, there are two capturing substrings, but when the first
554           data line is matched, the second, unset  substring  is  not  shown.  An
555           "internal"  unset  substring  is  shown as "<unset>", as for the second
556           data line.
557    
558               re> /(a)|(b)/
559             data> a
560              0: a
561              1: a
562             data> b
563              0: b
564              1: <unset>
565              2: b
566    
567         If the strings contain any non-printing characters, they are output  as         If the strings contain any non-printing characters, they are output  as
568         \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
569         the pattern. If the pattern has the /+ modifier, the  output  for  sub-         the pattern. See below for the definition of  non-printing  characters.
570         string  0 is followed by the the rest of the subject string, identified         If  the pattern has the /+ modifier, the output for substring 0 is fol-
571         by "0+" like this:         lowed by the the rest of the subject string, identified  by  "0+"  like
572           this:
573    
574             re> /cat/+             re> /cat/+
575           data> cataract           data> cataract
576            0: cat            0: cat
577            0+ aract            0+ aract
578    
579         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
580         matching attempts are output in sequence, like this:         matching attempts are output in sequence, like this:
581    
582             re> /\Bi(\w\w)/g             re> /\Bi(\w\w)/g
# Line 359  DEFAULT OUTPUT FROM PCRETEST Line 588  DEFAULT OUTPUT FROM PCRETEST
588            0: ipp            0: ipp
589            1: pp            1: pp
590    
591         "No match" is output only if the first match attempt fails.         "No match" is output only if the first match attempt fails. Here is  an
592           example  of a failure message (the offset 4 that is specified by \>4 is
593           past the end of the subject string):
594    
595               re> /xyz/
596             data> xyz\>4
597             Error -24 (bad offset value)
598    
599         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
600         is successfully matched, the substrings extracted  by  the  convenience         is  successfully  matched,  the substrings extracted by the convenience
601         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
602         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
603         (that  is,  the return from the extraction function) is given in paren-         (that is, the return from the extraction function) is given  in  paren-
604         theses after each string for \C and \G.         theses after each string for \C and \G.
605    
606         Note that while patterns can be continued over several lines  (a  plain         Note that whereas patterns can be continued over several lines (a plain
607         ">" prompt is used for continuations), data lines may not. However new-         ">" prompt is used for continuations), data lines may not. However new-
608         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,
609           etc., depending on the newline sequence setting).
610    
611    
612  OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION  OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION
# Line 388  OUTPUT FROM THE ALTERNATIVE MATCHING FUN Line 624  OUTPUT FROM THE ALTERNATIVE MATCHING FUN
624    
625         (Using  the  normal  matching function on this data finds only "tang".)         (Using  the  normal  matching function on this data finds only "tang".)
626         The longest matching string is always given first (and numbered  zero).         The longest matching string is always given first (and numbered  zero).
627           After a PCRE_ERROR_PARTIAL return, the output is "Partial match:", fol-
628           lowed by the partially matching  substring.  (Note  that  this  is  the
629           entire  substring  that  was inspected during the partial match; it may
630           include characters before the actual match start if a lookbehind asser-
631           tion, \K, \b, or \B was involved.)
632    
633         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
634         resumes at the end of the longest match. For example:         at the end of the longest match. For example:
635    
636             re> /(tang|tangerine|tan)/g             re> /(tang|tangerine|tan)/g
637           data> yellow tangerine and tangy sultana\D           data> yellow tangerine and tangy sultana\D
# Line 413  RESTARTING AFTER A PARTIAL MATCH Line 654  RESTARTING AFTER A PARTIAL MATCH
654         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
655         escape sequence. For example:         escape sequence. For example:
656    
657             re> /^?(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)$/             re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
658           data> 23ja\P\D           data> 23ja\P\D
659           Partial match: 23ja           Partial match: 23ja
660           data> n05\R\D           data> n05\R\D
# Line 454  CALLOUTS Line 695  CALLOUTS
695           +10 ^ ^           +10 ^ ^
696            0: E*            0: E*
697    
698         The  callout  function  in pcretest returns zero (carry on matching) by         If a pattern contains (*MARK) items, an additional line is output when-
699         default, but you can use a \C item in a data line (as described  above)         ever a change of latest mark is passed to  the  callout  function.  For
700         to change this.         example:
701    
702               re> /a(*MARK:X)bc/C
703             data> abc
704             --->abc
705              +0 ^       a
706              +1 ^^      (*MARK:X)
707             +10 ^^      b
708             Latest Mark: X
709             +11 ^ ^     c
710             +12 ^  ^
711              0: abc
712    
713           The  mark  changes between matching "a" and "b", but stays the same for
714           the rest of the match, so nothing more is output. If, as  a  result  of
715           backtracking,  the  mark  reverts to being unset, the text "<unset>" is
716           output.
717    
718           The callout function in pcretest returns zero (carry  on  matching)  by
719           default,  but you can use a \C item in a data line (as described above)
720           to change this and other parameters of the callout.
721    
722         Inserting  callouts can be helpful when using pcretest to check compli-         Inserting callouts can be helpful when using pcretest to check  compli-
723         cated regular expressions. For further information about callouts,  see         cated  regular expressions. For further information about callouts, see
724         the pcrecallout documentation.         the pcrecallout documentation.
725    
726    
727    NON-PRINTING CHARACTERS
728    
729           When pcretest is outputting text in the compiled version of a  pattern,
730           bytes  other  than 32-126 are always treated as non-printing characters
731           are are therefore shown as hex escapes.
732    
733           When pcretest is outputting text that is a matched part  of  a  subject
734           string,  it behaves in the same way, unless a different locale has been
735           set for the  pattern  (using  the  /L  modifier).  In  this  case,  the
736           isprint() function to distinguish printing and non-printing characters.
737    
738    
739  SAVING AND RELOADING COMPILED PATTERNS  SAVING AND RELOADING COMPILED PATTERNS
740    
741         The  facilities  described  in  this section are not available when the         The  facilities  described  in  this section are not available when the
742         POSIX inteface to PCRE is being used, that is, when the /P pattern mod-         POSIX interface to PCRE is being used, that is,  when  the  /P  pattern
743         ifier is specified.         modifier is specified.
744    
745         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
746         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
# Line 476  SAVING AND RELOADING COMPILED PATTERNS Line 749  SAVING AND RELOADING COMPILED PATTERNS
749           /pattern/im >/some/file           /pattern/im >/some/file
750    
751         See  the pcreprecompile documentation for a discussion about saving and         See  the pcreprecompile documentation for a discussion about saving and
752         re-using compiled patterns.         re-using compiled patterns.  Note that if the pattern was  successfully
753           studied with JIT optimization, the JIT data cannot be saved.
754    
755         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
756         length  of  the  compiled  pattern  data  followed by the length of the         length of the compiled pattern data  followed  by  the  length  of  the
757         optional study data, each written as four  bytes  in  big-endian  order         optional  study  data,  each  written as four bytes in big-endian order
758         (most  significant  byte  first). If there is no study data (either the         (most significant byte first). If there is no study  data  (either  the
759         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-
760         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
761         compiled pattern. If there is additional study data, this follows imme-         compiled  pattern.  If  there is additional study data, this (excluding
762         diately  after  the  compiled pattern. After writing the file, pcretest         any JIT data) follows immediately after  the  compiled  pattern.  After
763         expects to read a new pattern.         writing the file, pcretest expects to read a new pattern.
764    
765         A saved pattern can be reloaded into pcretest by specifing < and a file         A  saved  pattern  can  be reloaded into pcretest by specifying < and a
766         name  instead  of  a pattern. The name of the file must not contain a <         file name instead of a pattern. The name of the file must not contain a
767         character, as otherwise pcretest will interpret the line as  a  pattern         < character, as otherwise pcretest will interpret the line as a pattern
768         delimited by < characters.  For example:         delimited by < characters.  For example:
769    
770            re> </some/file            re> </some/file
771           Compiled regex loaded from /some/file           Compiled pattern loaded from /some/file
772           No study data           No study data
773    
774         When  the pattern has been loaded, pcretest proceeds to read data lines         If the pattern was previously studied with the  JIT  optimization,  the
775         in the usual way.         JIT  information cannot be saved and restored, and so is lost. When the
776           pattern has been loaded, pcretest proceeds to read data  lines  in  the
777         You can copy a file written by pcretest to a different host and  reload         usual way.
778         it  there,  even  if the new host has opposite endianness to the one on  
779         which the pattern was compiled. For example, you can compile on an  i86         You  can copy a file written by pcretest to a different host and reload
780           it there, even if the new host has opposite endianness to  the  one  on
781           which  the pattern was compiled. For example, you can compile on an i86
782         machine and run on a SPARC machine.         machine and run on a SPARC machine.
783    
784         File  names  for  saving and reloading can be absolute or relative, but         File names for saving and reloading can be absolute  or  relative,  but
785         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
786         a tilde (~) is not available.         a tilde (~) is not available.
787    
788         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-
789         ing and experimentation. It is not intended for production use  because         ing  and experimentation. It is not intended for production use because
790         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
791         no facility for supplying  custom  character  tables  for  use  with  a         no  facility  for  supplying  custom  character  tables  for use with a
792         reloaded  pattern.  If  the  original  pattern was compiled with custom         reloaded pattern. If the original  pattern  was  compiled  with  custom
793         tables, an attempt to match a subject string using a  reloaded  pattern         tables,  an  attempt to match a subject string using a reloaded pattern
794         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
795         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.
796    
797    
798    SEE ALSO
799    
800           pcre(3), pcreapi(3), pcrecallout(3), pcrejit, pcrematching(3), pcrepar-
801           tial(d), pcrepattern(3), pcreprecompile(3).
802    
803    
804  AUTHOR  AUTHOR
805    
806         Philip Hazel         Philip Hazel
807         University Computing Service,         University Computing Service
808         Cambridge CB2 3QG, England.         Cambridge CB2 3QH, England.
809    
810    
811    REVISION
812    
813  Last updated: 28 February 2005         Last updated: 02 December 2011
814  Copyright (c) 1997-2005 University of Cambridge.         Copyright (c) 1997-2011 University of Cambridge.

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