1PCRETEST(1) General Commands Manual PCRETEST(1)
2
3
4
6 pcretest - a program for testing Perl-compatible regular expressions.
7
9
10 pcretest [options] [source] [destination]
11
12 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
14 expressions. This document describes the features of the test program;
15 for details of the regular expressions themselves, see the pcrepattern
16 documentation. For details of the PCRE library function calls and their
17 options, see the pcreapi documentation.
18
20
21 -b Behave as if each regex has the /B (show bytecode) modifier;
22 the internal form is output after compilation.
23
24 -C Output the version number of the PCRE library, and all avail‐
25 able information about the optional features that are
26 included, and then exit.
27
28 -d Behave as if each regex has the /D (debug) modifier; the
29 internal form and information about the compiled pattern is
30 output after compilation; -d is equivalent to -b -i.
31
32 -dfa Behave as if each data line contains the \D escape sequence;
33 this causes the alternative matching function,
34 pcre_dfa_exec(), to be used instead of the standard
35 pcre_exec() function (more detail is given below).
36
37 -help Output a brief summary these options and then exit.
38
39 -i Behave as if each regex has the /I modifier; information
40 about the compiled pattern is given after compilation.
41
42 -M Behave as if each data line contains the \M escape sequence;
43 this causes PCRE to discover the minimum MATCH_LIMIT and
44 MATCH_LIMIT_RECURSION settings by calling pcre_exec() repeat‐
45 edly with different limits.
46
47 -m Output the size of each compiled pattern after it has been
48 compiled. This is equivalent to adding /M to each regular
49 expression. For compatibility with earlier versions of
50 pcretest, -s is a synonym for -m.
51
52 -o osize Set the number of elements in the output vector that is used
53 when calling pcre_exec() or pcre_dfa_exec() to be osize. The
54 default value is 45, which is enough for 14 capturing subex‐
55 pressions for pcre_exec() or 22 different matches for
56 pcre_dfa_exec(). The vector size can be changed for individ‐
57 ual matching calls by including \O in the data line (see
58 below).
59
60 -p Behave as if each regex has the /P modifier; the POSIX wrap‐
61 per API is used to call PCRE. None of the other options has
62 any effect when -p is set.
63
64 -q Do not output the version number of pcretest at the start of
65 execution.
66
67 -S size On Unix-like systems, set the size of the runtime stack to
68 size megabytes.
69
70 -t Run each compile, study, and match many times with a timer,
71 and output resulting time per compile or match (in millisec‐
72 onds). Do not set -m with -t, because you will then get the
73 size output a zillion times, and the timing will be dis‐
74 torted. You can control the number of iterations that are
75 used for timing by following -t with a number (as a separate
76 item on the command line). For example, "-t 1000" would iter‐
77 ate 1000 times. The default is to iterate 500000 times.
78
79 -tm This is like -t except that it times only the matching phase,
80 not the compile or study phases.
81
83
84 If pcretest is given two filename arguments, it reads from the first
85 and writes to the second. If it is given only one filename argument, it
86 reads from that file and writes to stdout. Otherwise, it reads from
87 stdin and writes to stdout, and prompts for each line of input, using
88 "re>" to prompt for regular expressions, and "data>" to prompt for data
89 lines.
90
91 When pcretest is built, a configuration option can specify that it
92 should be linked with the libreadline library. When this is done, if
93 the input is from a terminal, it is read using the readline() function.
94 This provides line-editing and history facilities. The output from the
95 -help option states whether or not readline() will be used.
96
97 The program handles any number of sets of input on a single input file.
98 Each set starts with a regular expression, and continues with any num‐
99 ber of data lines to be matched against the pattern.
100
101 Each data line is matched separately and independently. If you want to
102 do multi-line matches, you have to use the \n escape sequence (or \r or
103 \r\n, etc., depending on the newline setting) in a single line of input
104 to encode the newline sequences. There is no limit on the length of
105 data lines; the input buffer is automatically extended if it is too
106 small.
107
108 An empty line signals the end of the data lines, at which point a new
109 regular expression is read. The regular expressions are given enclosed
110 in any non-alphanumeric delimiters other than backslash, for example:
111
112 /(a|bc)x+yz/
113
114 White space before the initial delimiter is ignored. A regular expres‐
115 sion may be continued over several input lines, in which case the new‐
116 line characters are included within it. It is possible to include the
117 delimiter within the pattern by escaping it, for example
118
119 /abc\/def/
120
121 If you do so, the escape and the delimiter form part of the pattern,
122 but since delimiters are always non-alphanumeric, this does not affect
123 its interpretation. If the terminating delimiter is immediately fol‐
124 lowed by a backslash, for example,
125
126 /abc/\
127
128 then a backslash is added to the end of the pattern. This is done to
129 provide a way of testing the error condition that arises if a pattern
130 finishes with a backslash, because
131
132 /abc\/
133
134 is interpreted as the first line of a pattern that starts with "abc/",
135 causing pcretest to read the next line as a continuation of the regular
136 expression.
137
139
140 A pattern may be followed by any number of modifiers, which are mostly
141 single characters. Following Perl usage, these are referred to below
142 as, for example, "the /i modifier", even though the delimiter of the
143 pattern need not always be a slash, and no slash is used when writing
144 modifiers. Whitespace may appear between the final pattern delimiter
145 and the first modifier, and between the modifiers themselves.
146
147 The /i, /m, /s, and /x modifiers set the PCRE_CASELESS, PCRE_MULTILINE,
148 PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when pcre_com‐
149 pile() is called. These four modifier letters have the same effect as
150 they do in Perl. For example:
151
152 /caseless/i
153
154 The following table shows additional modifiers for setting PCRE com‐
155 pile-time options that do not correspond to anything in Perl:
156
157 /8 PCRE_UTF8
158 /? PCRE_NO_UTF8_CHECK
159 /A PCRE_ANCHORED
160 /C PCRE_AUTO_CALLOUT
161 /E PCRE_DOLLAR_ENDONLY
162 /f PCRE_FIRSTLINE
163 /J PCRE_DUPNAMES
164 /N PCRE_NO_AUTO_CAPTURE
165 /U PCRE_UNGREEDY
166 /W PCRE_UCP
167 /X PCRE_EXTRA
168 /<JS> PCRE_JAVASCRIPT_COMPAT
169 /<cr> PCRE_NEWLINE_CR
170 /<lf> PCRE_NEWLINE_LF
171 /<crlf> PCRE_NEWLINE_CRLF
172 /<anycrlf> PCRE_NEWLINE_ANYCRLF
173 /<any> PCRE_NEWLINE_ANY
174 /<bsr_anycrlf> PCRE_BSR_ANYCRLF
175 /<bsr_unicode> PCRE_BSR_UNICODE
176
177 The modifiers that are enclosed in angle brackets are literal strings
178 as shown, including the angle brackets, but the letters can be in
179 either case. This example sets multiline matching with CRLF as the line
180 ending sequence:
181
182 /^abc/m<crlf>
183
184 As well as turning on the PCRE_UTF8 option, the /8 modifier also causes
185 any non-printing characters in output strings to be printed using the
186 \x{hh...} notation if they are valid UTF-8 sequences. Full details of
187 the PCRE options are given in the pcreapi documentation.
188
189 Finding all matches in a string
190
191 Searching for all possible matches within each subject string can be
192 requested by the /g or /G modifier. After finding a match, PCRE is
193 called again to search the remainder of the subject string. The differ‐
194 ence between /g and /G is that the former uses the startoffset argument
195 to pcre_exec() to start searching at a new point within the entire
196 string (which is in effect what Perl does), whereas the latter passes
197 over a shortened substring. This makes a difference to the matching
198 process if the pattern begins with a lookbehind assertion (including \b
199 or \B).
200
201 If any call to pcre_exec() in a /g or /G sequence matches an empty
202 string, the next call is done with the PCRE_NOTEMPTY_ATSTART and
203 PCRE_ANCHORED flags set in order to search for another, non-empty,
204 match at the same point. If this second match fails, the start offset
205 is advanced by one character, and the normal match is retried. This
206 imitates the way Perl handles such cases when using the /g modifier or
207 the split() function.
208
209 Other modifiers
210
211 There are yet more modifiers for controlling the way pcretest operates.
212
213 The /+ modifier requests that as well as outputting the substring that
214 matched the entire pattern, pcretest should in addition output the
215 remainder of the subject string. This is useful for tests where the
216 subject contains multiple copies of the same substring.
217
218 The /B modifier is a debugging feature. It requests that pcretest out‐
219 put a representation of the compiled byte code after compilation. Nor‐
220 mally this information contains length and offset values; however, if
221 /Z is also present, this data is replaced by spaces. This is a special
222 feature for use in the automatic test scripts; it ensures that the same
223 output is generated for different internal link sizes.
224
225 The /D modifier is a PCRE debugging feature, and is equivalent to /BI,
226 that is, both the /B and the /I modifiers.
227
228 The /F modifier causes pcretest to flip the byte order of the fields in
229 the compiled pattern that contain 2-byte and 4-byte numbers. This
230 facility is for testing the feature in PCRE that allows it to execute
231 patterns that were compiled on a host with a different endianness. This
232 feature is not available when the POSIX interface to PCRE is being
233 used, that is, when the /P pattern modifier is specified. See also the
234 section about saving and reloading compiled patterns below.
235
236 The /I modifier requests that pcretest output information about the
237 compiled pattern (whether it is anchored, has a fixed first character,
238 and so on). It does this by calling pcre_fullinfo() after compiling a
239 pattern. If the pattern is studied, the results of that are also out‐
240 put.
241
242 The /K modifier requests pcretest to show names from backtracking con‐
243 trol verbs that are returned from calls to pcre_exec(). It causes
244 pcretest to create a pcre_extra block if one has not already been cre‐
245 ated by a call to pcre_study(), and to set the PCRE_EXTRA_MARK flag and
246 the mark field within it, every time that pcre_exec() is called. If the
247 variable that the mark field points to is non-NULL for a match, non-
248 match, or partial match, pcretest prints the string to which it points.
249 For a match, this is shown on a line by itself, tagged with "MK:". For
250 a non-match it is added to the message.
251
252 The /L modifier must be followed directly by the name of a locale, for
253 example,
254
255 /pattern/Lfr_FR
256
257 For this reason, it must be the last modifier. The given locale is set,
258 pcre_maketables() is called to build a set of character tables for the
259 locale, and this is then passed to pcre_compile() when compiling the
260 regular expression. Without an /L (or /T) modifier, NULL is passed as
261 the tables pointer; that is, /L applies only to the expression on which
262 it appears.
263
264 The /M modifier causes the size of memory block used to hold the com‐
265 piled pattern to be output.
266
267 The /S modifier causes pcre_study() to be called after the expression
268 has been compiled, and the results used when the expression is matched.
269
270 The /T modifier must be followed by a single digit. It causes a spe‐
271 cific set of built-in character tables to be passed to pcre_compile().
272 It is used in the standard PCRE tests to check behaviour with different
273 character tables. The digit specifies the tables as follows:
274
275 0 the default ASCII tables, as distributed in
276 pcre_chartables.c.dist
277 1 a set of tables defining ISO 8859 characters
278
279 In table 1, some characters whose codes are greater than 128 are iden‐
280 tified as letters, digits, spaces, etc.
281
282 Using the POSIX wrapper API
283
284 The /P modifier causes pcretest to call PCRE via the POSIX wrapper API
285 rather than its native API. When /P is set, the following modifiers set
286 options for the regcomp() function:
287
288 /i REG_ICASE
289 /m REG_NEWLINE
290 /N REG_NOSUB
291 /s REG_DOTALL )
292 /U REG_UNGREEDY ) These options are not part of
293 /W REG_UCP ) the POSIX standard
294 /8 REG_UTF8 )
295
296 The /+ modifier works as described above. All other modifiers are
297 ignored.
298
300
301 Before each data line is passed to pcre_exec(), leading and trailing
302 whitespace is removed, and it is then scanned for \ escapes. Some of
303 these are pretty esoteric features, intended for checking out some of
304 the more complicated features of PCRE. If you are just testing "ordi‐
305 nary" regular expressions, you probably don't need any of these. The
306 following escapes are recognized:
307
308 \a alarm (BEL, \x07)
309 \b backspace (\x08)
310 \e escape (\x27)
311 \f formfeed (\x0c)
312 \n newline (\x0a)
313 \qdd set the PCRE_MATCH_LIMIT limit to dd
314 (any number of digits)
315 \r carriage return (\x0d)
316 \t tab (\x09)
317 \v vertical tab (\x0b)
318 \nnn octal character (up to 3 octal digits)
319 \xhh hexadecimal character (up to 2 hex digits)
320 \x{hh...} hexadecimal character, any number of digits
321 in UTF-8 mode
322 \A pass the PCRE_ANCHORED option to pcre_exec()
323 or pcre_dfa_exec()
324 \B pass the PCRE_NOTBOL option to pcre_exec()
325 or pcre_dfa_exec()
326 \Cdd call pcre_copy_substring() for substring dd
327 after a successful match (number less than 32)
328 \Cname call pcre_copy_named_substring() for substring
329 "name" after a successful match (name termin-
330 ated by next non alphanumeric character)
331 \C+ show the current captured substrings at callout
332 time
333 \C- do not supply a callout function
334 \C!n return 1 instead of 0 when callout number n is
335 reached
336 \C!n!m return 1 instead of 0 when callout number n is
337 reached for the nth time
338 \C*n pass the number n (may be negative) as callout
339 data; this is used as the callout return value
340 \D use the pcre_dfa_exec() match function
341 \F only shortest match for pcre_dfa_exec()
342 \Gdd call pcre_get_substring() for substring dd
343 after a successful match (number less than 32)
344 \Gname call pcre_get_named_substring() for substring
345 "name" after a successful match (name termin-
346 ated by next non-alphanumeric character)
347 \L call pcre_get_substringlist() after a
348 successful match
349 \M discover the minimum MATCH_LIMIT and
350 MATCH_LIMIT_RECURSION settings
351 \N pass the PCRE_NOTEMPTY option to pcre_exec()
352 or pcre_dfa_exec(); if used twice, pass the
353 PCRE_NOTEMPTY_ATSTART option
354 \Odd set the size of the output vector passed to
355 pcre_exec() to dd (any number of digits)
356 \P pass the PCRE_PARTIAL_SOFT option to pcre_exec()
357 or pcre_dfa_exec(); if used twice, pass the
358 PCRE_PARTIAL_HARD option
359 \Qdd set the PCRE_MATCH_LIMIT_RECURSION limit to dd
360 (any number of digits)
361 \R pass the PCRE_DFA_RESTART option to pcre_dfa_exec()
362 \S output details of memory get/free calls during matching
363 \Y pass the PCRE_NO_START_OPTIMIZE option to pcre_exec()
364 or pcre_dfa_exec()
365 \Z pass the PCRE_NOTEOL option to pcre_exec()
366 or pcre_dfa_exec()
367 \? pass the PCRE_NO_UTF8_CHECK option to
368 pcre_exec() or pcre_dfa_exec()
369 \>dd start the match at offset dd (any number of digits);
370 this sets the startoffset argument for pcre_exec()
371 or pcre_dfa_exec()
372 \<cr> pass the PCRE_NEWLINE_CR option to pcre_exec()
373 or pcre_dfa_exec()
374 \<lf> pass the PCRE_NEWLINE_LF option to pcre_exec()
375 or pcre_dfa_exec()
376 \<crlf> pass the PCRE_NEWLINE_CRLF option to pcre_exec()
377 or pcre_dfa_exec()
378 \<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to pcre_exec()
379 or pcre_dfa_exec()
380 \<any> pass the PCRE_NEWLINE_ANY option to pcre_exec()
381 or pcre_dfa_exec()
382
383 The escapes that specify line ending sequences are literal strings,
384 exactly as shown. No more than one newline setting should be present in
385 any data line.
386
387 A backslash followed by anything else just escapes the anything else.
388 If the very last character is a backslash, it is ignored. This gives a
389 way of passing an empty line as data, since a real empty line termi‐
390 nates the data input.
391
392 If \M is present, pcretest calls pcre_exec() several times, with dif‐
393 ferent values in the match_limit and match_limit_recursion fields of
394 the pcre_extra data structure, until it finds the minimum numbers for
395 each parameter that allow pcre_exec() to complete. The match_limit num‐
396 ber is a measure of the amount of backtracking that takes place, and
397 checking it out can be instructive. For most simple matches, the number
398 is quite small, but for patterns with very large numbers of matching
399 possibilities, it can become large very quickly with increasing length
400 of subject string. The match_limit_recursion number is a measure of how
401 much stack (or, if PCRE is compiled with NO_RECURSE, how much heap)
402 memory is needed to complete the match attempt.
403
404 When \O is used, the value specified may be higher or lower than the
405 size set by the -O command line option (or defaulted to 45); \O applies
406 only to the call of pcre_exec() for the line in which it appears.
407
408 If the /P modifier was present on the pattern, causing the POSIX wrap‐
409 per API to be used, the only option-setting sequences that have any
410 effect are \B, \N, and \Z, causing REG_NOTBOL, REG_NOTEMPTY, and
411 REG_NOTEOL, respectively, to be passed to regexec().
412
413 The use of \x{hh...} to represent UTF-8 characters is not dependent on
414 the use of the /8 modifier on the pattern. It is recognized always.
415 There may be any number of hexadecimal digits inside the braces. The
416 result is from one to six bytes, encoded according to the original
417 UTF-8 rules of RFC 2279. This allows for values in the range 0 to
418 0x7FFFFFFF. Note that not all of those are valid Unicode code points,
419 or indeed valid UTF-8 characters according to the later rules in RFC
420 3629.
421
423
424 By default, pcretest uses the standard PCRE matching function,
425 pcre_exec() to match each data line. From release 6.0, PCRE supports an
426 alternative matching function, pcre_dfa_test(), which operates in a
427 different way, and has some restrictions. The differences between the
428 two functions are described in the pcrematching documentation.
429
430 If a data line contains the \D escape sequence, or if the command line
431 contains the -dfa option, the alternative matching function is called.
432 This function finds all possible matches at a given point. If, however,
433 the \F escape sequence is present in the data line, it stops after the
434 first match is found. This is always the shortest possible match.
435
437
438 This section describes the output when the normal matching function,
439 pcre_exec(), is being used.
440
441 When a match succeeds, pcretest outputs the list of captured substrings
442 that pcre_exec() returns, starting with number 0 for the string that
443 matched the whole pattern. Otherwise, it outputs "No match" when the
444 return is PCRE_ERROR_NOMATCH, and "Partial match:" followed by the par‐
445 tially matching substring when pcre_exec() returns PCRE_ERROR_PARTIAL.
446 For any other returns, it outputs the PCRE negative error number. Here
447 is an example of an interactive pcretest run.
448
449 $ pcretest
450 PCRE version 7.0 30-Nov-2006
451
452 re> /^abc(\d+)/
453 data> abc123
454 0: abc123
455 1: 123
456 data> xyz
457 No match
458
459 Note that unset capturing substrings that are not followed by one that
460 is set are not returned by pcre_exec(), and are not shown by pcretest.
461 In the following example, there are two capturing substrings, but when
462 the first data line is matched, the second, unset substring is not
463 shown. An "internal" unset substring is shown as "<unset>", as for the
464 second data line.
465
466 re> /(a)|(b)/
467 data> a
468 0: a
469 1: a
470 data> b
471 0: b
472 1: <unset>
473 2: b
474
475 If the strings contain any non-printing characters, they are output as
476 \0x escapes, or as \x{...} escapes if the /8 modifier was present on
477 the pattern. See below for the definition of non-printing characters.
478 If the pattern has the /+ modifier, the output for substring 0 is fol‐
479 lowed by the the rest of the subject string, identified by "0+" like
480 this:
481
482 re> /cat/+
483 data> cataract
484 0: cat
485 0+ aract
486
487 If the pattern has the /g or /G modifier, the results of successive
488 matching attempts are output in sequence, like this:
489
490 re> /\Bi(\w\w)/g
491 data> Mississippi
492 0: iss
493 1: ss
494 0: iss
495 1: ss
496 0: ipp
497 1: pp
498
499 "No match" is output only if the first match attempt fails.
500
501 If any of the sequences \C, \G, or \L are present in a data line that
502 is successfully matched, the substrings extracted by the convenience
503 functions are output with C, G, or L after the string number instead of
504 a colon. This is in addition to the normal full list. The string length
505 (that is, the return from the extraction function) is given in paren‐
506 theses after each string for \C and \G.
507
508 Note that whereas patterns can be continued over several lines (a plain
509 ">" prompt is used for continuations), data lines may not. However new‐
510 lines can be included in data by means of the \n escape (or \r, \r\n,
511 etc., depending on the newline sequence setting).
512
514
515 When the alternative matching function, pcre_dfa_exec(), is used (by
516 means of the \D escape sequence or the -dfa command line option), the
517 output consists of a list of all the matches that start at the first
518 point in the subject where there is at least one match. For example:
519
520 re> /(tang|tangerine|tan)/
521 data> yellow tangerine\D
522 0: tangerine
523 1: tang
524 2: tan
525
526 (Using the normal matching function on this data finds only "tang".)
527 The longest matching string is always given first (and numbered zero).
528 After a PCRE_ERROR_PARTIAL return, the output is "Partial match:", fol‐
529 lowed by the partially matching substring.
530
531 If /g is present on the pattern, the search for further matches resumes
532 at the end of the longest match. For example:
533
534 re> /(tang|tangerine|tan)/g
535 data> yellow tangerine and tangy sultana\D
536 0: tangerine
537 1: tang
538 2: tan
539 0: tang
540 1: tan
541 0: tan
542
543 Since the matching function does not support substring capture, the
544 escape sequences that are concerned with captured substrings are not
545 relevant.
546
548
549 When the alternative matching function has given the PCRE_ERROR_PARTIAL
550 return, indicating that the subject partially matched the pattern, you
551 can restart the match with additional subject data by means of the \R
552 escape sequence. For example:
553
554 re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
555 data> 23ja\P\D
556 Partial match: 23ja
557 data> n05\R\D
558 0: n05
559
560 For further information about partial matching, see the pcrepartial
561 documentation.
562
564
565 If the pattern contains any callout requests, pcretest's callout func‐
566 tion is called during matching. This works with both matching func‐
567 tions. By default, the called function displays the callout number, the
568 start and current positions in the text at the callout time, and the
569 next pattern item to be tested. For example, the output
570
571 --->pqrabcdef
572 0 ^ ^ \d
573
574 indicates that callout number 0 occurred for a match attempt starting
575 at the fourth character of the subject string, when the pointer was at
576 the seventh character of the data, and when the next pattern item was
577 \d. Just one circumflex is output if the start and current positions
578 are the same.
579
580 Callouts numbered 255 are assumed to be automatic callouts, inserted as
581 a result of the /C pattern modifier. In this case, instead of showing
582 the callout number, the offset in the pattern, preceded by a plus, is
583 output. For example:
584
585 re> /\d?[A-E]\*/C
586 data> E*
587 --->E*
588 +0 ^ \d?
589 +3 ^ [A-E]
590 +8 ^^ \*
591 +10 ^ ^
592 0: E*
593
594 The callout function in pcretest returns zero (carry on matching) by
595 default, but you can use a \C item in a data line (as described above)
596 to change this.
597
598 Inserting callouts can be helpful when using pcretest to check compli‐
599 cated regular expressions. For further information about callouts, see
600 the pcrecallout documentation.
601
603
604 When pcretest is outputting text in the compiled version of a pattern,
605 bytes other than 32-126 are always treated as non-printing characters
606 are are therefore shown as hex escapes.
607
608 When pcretest is outputting text that is a matched part of a subject
609 string, it behaves in the same way, unless a different locale has been
610 set for the pattern (using the /L modifier). In this case, the
611 isprint() function to distinguish printing and non-printing characters.
612
614
615 The facilities described in this section are not available when the
616 POSIX inteface to PCRE is being used, that is, when the /P pattern mod‐
617 ifier is specified.
618
619 When the POSIX interface is not in use, you can cause pcretest to write
620 a compiled pattern to a file, by following the modifiers with > and a
621 file name. For example:
622
623 /pattern/im >/some/file
624
625 See the pcreprecompile documentation for a discussion about saving and
626 re-using compiled patterns.
627
628 The data that is written is binary. The first eight bytes are the
629 length of the compiled pattern data followed by the length of the
630 optional study data, each written as four bytes in big-endian order
631 (most significant byte first). If there is no study data (either the
632 pattern was not studied, or studying did not return any data), the sec‐
633 ond length is zero. The lengths are followed by an exact copy of the
634 compiled pattern. If there is additional study data, this follows imme‐
635 diately after the compiled pattern. After writing the file, pcretest
636 expects to read a new pattern.
637
638 A saved pattern can be reloaded into pcretest by specifing < and a file
639 name instead of a pattern. The name of the file must not contain a <
640 character, as otherwise pcretest will interpret the line as a pattern
641 delimited by < characters. For example:
642
643 re> </some/file
644 Compiled regex loaded from /some/file
645 No study data
646
647 When the pattern has been loaded, pcretest proceeds to read data lines
648 in the usual way.
649
650 You can copy a file written by pcretest to a different host and reload
651 it there, even if the new host has opposite endianness to the one on
652 which the pattern was compiled. For example, you can compile on an i86
653 machine and run on a SPARC machine.
654
655 File names for saving and reloading can be absolute or relative, but
656 note that the shell facility of expanding a file name that starts with
657 a tilde (~) is not available.
658
659 The ability to save and reload files in pcretest is intended for test‐
660 ing and experimentation. It is not intended for production use because
661 only a single pattern can be written to a file. Furthermore, there is
662 no facility for supplying custom character tables for use with a
663 reloaded pattern. If the original pattern was compiled with custom
664 tables, an attempt to match a subject string using a reloaded pattern
665 is likely to cause pcretest to crash. Finally, if you attempt to load
666 a file that is not in the correct format, the result is undefined.
667
669
670 pcre(3), pcreapi(3), pcrecallout(3), pcrematching(3), pcrepartial(d),
671 pcrepattern(3), pcreprecompile(3).
672
674
675 Philip Hazel
676 University Computing Service
677 Cambridge CB2 3QH, England.
678
680
681 Last updated: 14 June 2010
682 Copyright (c) 1997-2010 University of Cambridge.
683
684
685
686 PCRETEST(1)