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Revision 780 - (hide annotations) (download)
Fri Dec 2 11:39:21 2011 UTC (2 years, 4 months ago) by ph10
File size: 36861 byte(s)
Preserve the size of JIT compiled code. Add PCRE_INFO_JITSIZE and use it for
the /M option in pcretest. 

1 nigel 53 .TH PCRETEST 1
2     .SH NAME
3     pcretest - a program for testing Perl-compatible regular expressions.
4     .SH SYNOPSIS
5 nigel 75 .rs
6     .sp
7 ph10 612 .B pcretest "[options] [input file [output file]]"
8 nigel 91 .sp
9 nigel 75 \fBpcretest\fP was written as a test program for the PCRE regular expression
10 nigel 53 library itself, but it can also be used for experimenting with regular
11 nigel 63 expressions. This document describes the features of the test program; for
12     details of the regular expressions themselves, see the
13     .\" HREF
14 nigel 75 \fBpcrepattern\fP
15 nigel 63 .\"
16 nigel 75 documentation. For details of the PCRE library function calls and their
17     options, see the
18 nigel 63 .\" HREF
19 nigel 75 \fBpcreapi\fP
20 nigel 63 .\"
21 ph10 654 documentation. The input for \fBpcretest\fP is a sequence of regular expression
22     patterns and strings to be matched, as described below. The output shows the
23     result of each match. Options on the command line and the patterns control PCRE
24 ph10 612 options and exactly what is output.
25 nigel 75 .
26     .
27 ph10 612 .SH COMMAND LINE OPTIONS
28 nigel 63 .rs
29 nigel 53 .TP 10
30 nigel 93 \fB-b\fP
31 ph10 612 Behave as if each pattern has the \fB/B\fP (show byte code) modifier; the
32 ph10 599 internal form is output after compilation.
33 nigel 93 .TP 10
34 nigel 75 \fB-C\fP
35 nigel 63 Output the version number of the PCRE library, and all available information
36     about the optional features that are included, and then exit.
37     .TP 10
38 nigel 75 \fB-d\fP
39 ph10 612 Behave as if each pattern has the \fB/D\fP (debug) modifier; the internal
40 nigel 93 form and information about the compiled pattern is output after compilation;
41     \fB-d\fP is equivalent to \fB-b -i\fP.
42 nigel 53 .TP 10
43 nigel 77 \fB-dfa\fP
44     Behave as if each data line contains the \eD escape sequence; this causes the
45     alternative matching function, \fBpcre_dfa_exec()\fP, to be used instead of the
46     standard \fBpcre_exec()\fP function (more detail is given below).
47     .TP 10
48 nigel 93 \fB-help\fP
49     Output a brief summary these options and then exit.
50     .TP 10
51 nigel 75 \fB-i\fP
52 ph10 612 Behave as if each pattern has the \fB/I\fP modifier; information about the
53 nigel 53 compiled pattern is given after compilation.
54     .TP 10
55 ph10 386 \fB-M\fP
56     Behave as if each data line contains the \eM escape sequence; this causes
57 ph10 392 PCRE to discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings by
58 ph10 386 calling \fBpcre_exec()\fP repeatedly with different limits.
59     .TP 10
60 nigel 75 \fB-m\fP
61 nigel 53 Output the size of each compiled pattern after it has been compiled. This is
62 ph10 606 equivalent to adding \fB/M\fP to each regular expression.
63 nigel 53 .TP 10
64 nigel 75 \fB-o\fP \fIosize\fP
65     Set the number of elements in the output vector that is used when calling
66 nigel 93 \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP to be \fIosize\fP. The default value
67     is 45, which is enough for 14 capturing subexpressions for \fBpcre_exec()\fP or
68     22 different matches for \fBpcre_dfa_exec()\fP. The vector size can be
69     changed for individual matching calls by including \eO in the data line (see
70     below).
71 nigel 53 .TP 10
72 nigel 75 \fB-p\fP
73 ph10 612 Behave as if each pattern has the \fB/P\fP modifier; the POSIX wrapper API is
74 nigel 77 used to call PCRE. None of the other options has any effect when \fB-p\fP is
75     set.
76 nigel 53 .TP 10
77 nigel 91 \fB-q\fP
78 nigel 87 Do not output the version number of \fBpcretest\fP at the start of execution.
79     .TP 10
80 nigel 91 \fB-S\fP \fIsize\fP
81 ph10 599 On Unix-like systems, set the size of the run-time stack to \fIsize\fP
82 nigel 91 megabytes.
83     .TP 10
84 ph10 678 \fB-s\fP or \fB-s+\fP
85 ph10 612 Behave as if each pattern has the \fB/S\fP modifier; in other words, force each
86 ph10 678 pattern to be studied. If \fB-s+\fP is used, the PCRE_STUDY_JIT_COMPILE flag is
87     passed to \fBpcre_study()\fP, causing just-in-time optimization to be set up if
88     it is available. If the \fB/I\fP or \fB/D\fP option is present on a pattern
89     (requesting output about the compiled pattern), information about the result of
90     studying is not included when studying is caused only by \fB-s\fP and neither
91     \fB-i\fP nor \fB-d\fP is present on the command line. This behaviour means that
92     the output from tests that are run with and without \fB-s\fP should be
93     identical, except when options that output information about the actual running
94     of a match are set. The \fB-M\fP, \fB-t\fP, and \fB-tm\fP options, which give
95     information about resources used, are likely to produce different output with
96     and without \fB-s\fP. Output may also differ if the \fB/C\fP option is present
97     on an individual pattern. This uses callouts to trace the the matching process,
98     and this may be different between studied and non-studied patterns. If the
99     pattern contains (*MARK) items there may also be differences, for the same
100     reason. The \fB-s\fP command line option can be overridden for specific
101     patterns that should never be studied (see the \fB/S\fP pattern modifier
102     below).
103 ph10 606 .TP 10
104 nigel 75 \fB-t\fP
105 nigel 63 Run each compile, study, and match many times with a timer, and output
106 nigel 75 resulting time per compile or match (in milliseconds). Do not set \fB-m\fP with
107     \fB-t\fP, because you will then get the size output a zillion times, and the
108 nigel 93 timing will be distorted. You can control the number of iterations that are
109     used for timing by following \fB-t\fP with a number (as a separate item on the
110     command line). For example, "-t 1000" would iterate 1000 times. The default is
111     to iterate 500000 times.
112     .TP 10
113     \fB-tm\fP
114     This is like \fB-t\fP except that it times only the matching phase, not the
115     compile or study phases.
116 nigel 75 .
117     .
118 nigel 53 .SH DESCRIPTION
119 nigel 63 .rs
120     .sp
121 nigel 75 If \fBpcretest\fP is given two filename arguments, it reads from the first and
122 nigel 53 writes to the second. If it is given only one filename argument, it reads from
123     that file and writes to stdout. Otherwise, it reads from stdin and writes to
124     stdout, and prompts for each line of input, using "re>" to prompt for regular
125     expressions, and "data>" to prompt for data lines.
126 nigel 75 .P
127 ph10 289 When \fBpcretest\fP is built, a configuration option can specify that it should
128 ph10 287 be linked with the \fBlibreadline\fP library. When this is done, if the input
129     is from a terminal, it is read using the \fBreadline()\fP function. This
130     provides line-editing and history facilities. The output from the \fB-help\fP
131     option states whether or not \fBreadline()\fP will be used.
132     .P
133 nigel 53 The program handles any number of sets of input on a single input file. Each
134     set starts with a regular expression, and continues with any number of data
135 nigel 63 lines to be matched against the pattern.
136 nigel 75 .P
137     Each data line is matched separately and independently. If you want to do
138 nigel 91 multi-line matches, you have to use the \en escape sequence (or \er or \er\en,
139 nigel 93 etc., depending on the newline setting) in a single line of input to encode the
140     newline sequences. There is no limit on the length of data lines; the input
141 nigel 91 buffer is automatically extended if it is too small.
142 nigel 75 .P
143 nigel 63 An empty line signals the end of the data lines, at which point a new regular
144     expression is read. The regular expressions are given enclosed in any
145 nigel 91 non-alphanumeric delimiters other than backslash, for example:
146 nigel 75 .sp
147 nigel 53 /(a|bc)x+yz/
148 nigel 75 .sp
149 nigel 53 White space before the initial delimiter is ignored. A regular expression may
150     be continued over several input lines, in which case the newline characters are
151     included within it. It is possible to include the delimiter within the pattern
152     by escaping it, for example
153 nigel 75 .sp
154     /abc\e/def/
155     .sp
156 nigel 53 If you do so, the escape and the delimiter form part of the pattern, but since
157 nigel 75 delimiters are always non-alphanumeric, this does not affect its interpretation.
158 nigel 53 If the terminating delimiter is immediately followed by a backslash, for
159     example,
160 nigel 75 .sp
161     /abc/\e
162     .sp
163 nigel 53 then a backslash is added to the end of the pattern. This is done to provide a
164     way of testing the error condition that arises if a pattern finishes with a
165     backslash, because
166 nigel 75 .sp
167     /abc\e/
168     .sp
169 nigel 53 is interpreted as the first line of a pattern that starts with "abc/", causing
170     pcretest to read the next line as a continuation of the regular expression.
171 nigel 75 .
172     .
173     .SH "PATTERN MODIFIERS"
174 nigel 63 .rs
175     .sp
176 nigel 75 A pattern may be followed by any number of modifiers, which are mostly single
177     characters. Following Perl usage, these are referred to below as, for example,
178     "the \fB/i\fP modifier", even though the delimiter of the pattern need not
179 ph10 599 always be a slash, and no slash is used when writing modifiers. White space may
180 nigel 75 appear between the final pattern delimiter and the first modifier, and between
181     the modifiers themselves.
182     .P
183     The \fB/i\fP, \fB/m\fP, \fB/s\fP, and \fB/x\fP modifiers set the PCRE_CASELESS,
184     PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when
185     \fBpcre_compile()\fP is called. These four modifier letters have the same
186     effect as they do in Perl. For example:
187     .sp
188 nigel 53 /caseless/i
189 nigel 75 .sp
190 ph10 518 The following table shows additional modifiers for setting PCRE compile-time
191     options that do not correspond to anything in Perl:
192 nigel 75 .sp
193 ph10 518 \fB/8\fP PCRE_UTF8
194 ph10 535 \fB/?\fP PCRE_NO_UTF8_CHECK
195 ph10 231 \fB/A\fP PCRE_ANCHORED
196     \fB/C\fP PCRE_AUTO_CALLOUT
197     \fB/E\fP PCRE_DOLLAR_ENDONLY
198     \fB/f\fP PCRE_FIRSTLINE
199     \fB/J\fP PCRE_DUPNAMES
200     \fB/N\fP PCRE_NO_AUTO_CAPTURE
201     \fB/U\fP PCRE_UNGREEDY
202 ph10 535 \fB/W\fP PCRE_UCP
203 ph10 231 \fB/X\fP PCRE_EXTRA
204 ph10 579 \fB/Y\fP PCRE_NO_START_OPTIMIZE
205 ph10 345 \fB/<JS>\fP PCRE_JAVASCRIPT_COMPAT
206 ph10 231 \fB/<cr>\fP PCRE_NEWLINE_CR
207     \fB/<lf>\fP PCRE_NEWLINE_LF
208     \fB/<crlf>\fP PCRE_NEWLINE_CRLF
209     \fB/<anycrlf>\fP PCRE_NEWLINE_ANYCRLF
210     \fB/<any>\fP PCRE_NEWLINE_ANY
211     \fB/<bsr_anycrlf>\fP PCRE_BSR_ANYCRLF
212     \fB/<bsr_unicode>\fP PCRE_BSR_UNICODE
213 nigel 75 .sp
214 ph10 518 The modifiers that are enclosed in angle brackets are literal strings as shown,
215 ph10 612 including the angle brackets, but the letters within can be in either case.
216     This example sets multiline matching with CRLF as the line ending sequence:
217 nigel 93 .sp
218 ph10 612 /^abc/m<CRLF>
219 nigel 93 .sp
220 ph10 518 As well as turning on the PCRE_UTF8 option, the \fB/8\fP modifier also causes
221     any non-printing characters in output strings to be printed using the
222     \ex{hh...} notation if they are valid UTF-8 sequences. Full details of the PCRE
223     options are given in the
224 nigel 91 .\" HREF
225     \fBpcreapi\fP
226     .\"
227 ph10 535 documentation.
228 nigel 91 .
229     .
230     .SS "Finding all matches in a string"
231     .rs
232     .sp
233 nigel 53 Searching for all possible matches within each subject string can be requested
234 nigel 75 by the \fB/g\fP or \fB/G\fP modifier. After finding a match, PCRE is called
235 nigel 53 again to search the remainder of the subject string. The difference between
236 nigel 75 \fB/g\fP and \fB/G\fP is that the former uses the \fIstartoffset\fP argument to
237     \fBpcre_exec()\fP to start searching at a new point within the entire string
238 nigel 53 (which is in effect what Perl does), whereas the latter passes over a shortened
239     substring. This makes a difference to the matching process if the pattern
240 nigel 75 begins with a lookbehind assertion (including \eb or \eB).
241     .P
242     If any call to \fBpcre_exec()\fP in a \fB/g\fP or \fB/G\fP sequence matches an
243 ph10 442 empty string, the next call is done with the PCRE_NOTEMPTY_ATSTART and
244     PCRE_ANCHORED flags set in order to search for another, non-empty, match at the
245 ph10 566 same point. If this second match fails, the start offset is advanced, and the
246     normal match is retried. This imitates the way Perl handles such cases when
247 ph10 579 using the \fB/g\fP modifier or the \fBsplit()\fP function. Normally, the start
248     offset is advanced by one character, but if the newline convention recognizes
249     CRLF as a newline, and the current character is CR followed by LF, an advance
250 ph10 566 of two is used.
251 nigel 91 .
252     .
253     .SS "Other modifiers"
254     .rs
255     .sp
256 nigel 75 There are yet more modifiers for controlling the way \fBpcretest\fP
257 nigel 53 operates.
258 nigel 75 .P
259     The \fB/+\fP modifier requests that as well as outputting the substring that
260 ph10 616 matched the entire pattern, \fBpcretest\fP should in addition output the
261     remainder of the subject string. This is useful for tests where the subject
262     contains multiple copies of the same substring. If the \fB+\fP modifier appears
263 ph10 654 twice, the same action is taken for captured substrings. In each case the
264     remainder is output on the following line with a plus character following the
265 ph10 691 capture number. Note that this modifier must not immediately follow the /S
266 ph10 678 modifier because /S+ has another meaning.
267 nigel 75 .P
268 ph10 654 The \fB/=\fP modifier requests that the values of all potential captured
269 ph10 626 parentheses be output after a match by \fBpcre_exec()\fP. By default, only
270     those up to the highest one actually used in the match are output
271 ph10 654 (corresponding to the return code from \fBpcre_exec()\fP). Values in the
272     offsets vector corresponding to higher numbers should be set to -1, and these
273 ph10 626 are output as "<unset>". This modifier gives a way of checking that this is
274     happening.
275     .P
276 nigel 93 The \fB/B\fP modifier is a debugging feature. It requests that \fBpcretest\fP
277 ph10 123 output a representation of the compiled byte code after compilation. Normally
278 ph10 116 this information contains length and offset values; however, if \fB/Z\fP is
279     also present, this data is replaced by spaces. This is a special feature for
280     use in the automatic test scripts; it ensures that the same output is generated
281     for different internal link sizes.
282 nigel 93 .P
283     The \fB/D\fP modifier is a PCRE debugging feature, and is equivalent to
284 ph10 148 \fB/BI\fP, that is, both the \fB/B\fP and the \fB/I\fP modifiers.
285 nigel 75 .P
286     The \fB/F\fP modifier causes \fBpcretest\fP to flip the byte order of the
287     fields in the compiled pattern that contain 2-byte and 4-byte numbers. This
288     facility is for testing the feature in PCRE that allows it to execute patterns
289     that were compiled on a host with a different endianness. This feature is not
290     available when the POSIX interface to PCRE is being used, that is, when the
291     \fB/P\fP pattern modifier is specified. See also the section about saving and
292     reloading compiled patterns below.
293     .P
294 ph10 510 The \fB/I\fP modifier requests that \fBpcretest\fP output information about the
295     compiled pattern (whether it is anchored, has a fixed first character, and
296     so on). It does this by calling \fBpcre_fullinfo()\fP after compiling a
297     pattern. If the pattern is studied, the results of that are also output.
298 nigel 75 .P
299 ph10 510 The \fB/K\fP modifier requests \fBpcretest\fP to show names from backtracking
300     control verbs that are returned from calls to \fBpcre_exec()\fP. It causes
301     \fBpcretest\fP to create a \fBpcre_extra\fP block if one has not already been
302     created by a call to \fBpcre_study()\fP, and to set the PCRE_EXTRA_MARK flag
303     and the \fBmark\fP field within it, every time that \fBpcre_exec()\fP is
304     called. If the variable that the \fBmark\fP field points to is non-NULL for a
305 ph10 512 match, non-match, or partial match, \fBpcretest\fP prints the string to which
306     it points. For a match, this is shown on a line by itself, tagged with "MK:".
307 ph10 510 For a non-match it is added to the message.
308     .P
309     The \fB/L\fP modifier must be followed directly by the name of a locale, for
310     example,
311     .sp
312     /pattern/Lfr_FR
313     .sp
314     For this reason, it must be the last modifier. The given locale is set,
315     \fBpcre_maketables()\fP is called to build a set of character tables for the
316     locale, and this is then passed to \fBpcre_compile()\fP when compiling the
317 ph10 541 regular expression. Without an \fB/L\fP (or \fB/T\fP) modifier, NULL is passed
318     as the tables pointer; that is, \fB/L\fP applies only to the expression on
319     which it appears.
320 ph10 510 .P
321 nigel 75 The \fB/M\fP modifier causes the size of memory block used to hold the compiled
322 ph10 780 pattern to be output. This does not include the size of the \fBpcre\fP block;
323     it is just the actual compiled data. If the pattern is successfully studied
324     with the PCRE_STUDY_JIT_COMPILE option, the size of the JIT compiled code is
325     also output.
326 nigel 75 .P
327 ph10 612 If the \fB/S\fP modifier appears once, it causes \fBpcre_study()\fP to be
328     called after the expression has been compiled, and the results used when the
329 ph10 654 expression is matched. If \fB/S\fP appears twice, it suppresses studying, even
330     if it was requested externally by the \fB-s\fP command line option. This makes
331     it possible to specify that certain patterns are always studied, and others are
332     never studied, independently of \fB-s\fP. This feature is used in the test
333 ph10 612 files in a few cases where the output is different when the pattern is studied.
334 ph10 541 .P
335 ph10 691 If the \fB/S\fP modifier is immediately followed by a + character, the call to
336     \fBpcre_study()\fP is made with the PCRE_STUDY_JIT_COMPILE option, requesting
337     just-in-time optimization support if it is available. Note that there is also a
338     \fB/+\fP modifier; it must not be given immediately after \fB/S\fP because this
339     will be misinterpreted. If JIT studying is successful, it will automatically be
340     used when \fBpcre_exec()\fP is run, except when incompatible run-time options
341     are specified. These include the partial matching options; a complete list is
342 ph10 678 given in the
343     .\" HREF
344     \fBpcrejit\fP
345     .\"
346 ph10 691 documentation. See also the \fB\eJ\fP escape sequence below for a way of
347 ph10 678 setting the size of the JIT stack.
348     .P
349 ph10 545 The \fB/T\fP modifier must be followed by a single digit. It causes a specific
350     set of built-in character tables to be passed to \fBpcre_compile()\fP. It is
351     used in the standard PCRE tests to check behaviour with different character
352 ph10 541 tables. The digit specifies the tables as follows:
353     .sp
354 ph10 545 0 the default ASCII tables, as distributed in
355 ph10 541 pcre_chartables.c.dist
356     1 a set of tables defining ISO 8859 characters
357     .sp
358 ph10 545 In table 1, some characters whose codes are greater than 128 are identified as
359 ph10 541 letters, digits, spaces, etc.
360 nigel 75 .
361     .
362 ph10 518 .SS "Using the POSIX wrapper API"
363     .rs
364     .sp
365     The \fB/P\fP modifier causes \fBpcretest\fP to call PCRE via the POSIX wrapper
366 ph10 535 API rather than its native API. When \fB/P\fP is set, the following modifiers
367 ph10 518 set options for the \fBregcomp()\fP function:
368     .sp
369     /i REG_ICASE
370     /m REG_NEWLINE
371     /N REG_NOSUB
372     /s REG_DOTALL )
373 ph10 535 /U REG_UNGREEDY ) These options are not part of
374 ph10 518 /W REG_UCP ) the POSIX standard
375     /8 REG_UTF8 )
376     .sp
377     The \fB/+\fP modifier works as described above. All other modifiers are
378     ignored.
379     .
380     .
381 nigel 75 .SH "DATA LINES"
382 nigel 63 .rs
383     .sp
384 nigel 75 Before each data line is passed to \fBpcre_exec()\fP, leading and trailing
385 ph10 599 white space is removed, and it is then scanned for \e escapes. Some of these
386     are pretty esoteric features, intended for checking out some of the more
387 nigel 63 complicated features of PCRE. If you are just testing "ordinary" regular
388     expressions, you probably don't need any of these. The following escapes are
389 nigel 53 recognized:
390 nigel 75 .sp
391 nigel 93 \ea alarm (BEL, \ex07)
392     \eb backspace (\ex08)
393     \ee escape (\ex27)
394 ph10 599 \ef form feed (\ex0c)
395 nigel 93 \en newline (\ex0a)
396 nigel 91 .\" JOIN
397     \eqdd set the PCRE_MATCH_LIMIT limit to dd
398     (any number of digits)
399 nigel 93 \er carriage return (\ex0d)
400     \et tab (\ex09)
401     \ev vertical tab (\ex0b)
402 nigel 75 \ennn octal character (up to 3 octal digits)
403 ph10 579 always a byte unless > 255 in UTF-8 mode
404 ph10 570 \exhh hexadecimal byte (up to 2 hex digits)
405 nigel 75 .\" JOIN
406     \ex{hh...} hexadecimal character, any number of digits
407 nigel 63 in UTF-8 mode
408 nigel 91 .\" JOIN
409 nigel 75 \eA pass the PCRE_ANCHORED option to \fBpcre_exec()\fP
410 nigel 91 or \fBpcre_dfa_exec()\fP
411     .\" JOIN
412 nigel 75 \eB pass the PCRE_NOTBOL option to \fBpcre_exec()\fP
413 nigel 91 or \fBpcre_dfa_exec()\fP
414 nigel 75 .\" JOIN
415     \eCdd call pcre_copy_substring() for substring dd
416     after a successful match (number less than 32)
417     .\" JOIN
418     \eCname call pcre_copy_named_substring() for substring
419 nigel 63 "name" after a successful match (name termin-
420     ated by next non alphanumeric character)
421 nigel 75 .\" JOIN
422     \eC+ show the current captured substrings at callout
423 nigel 63 time
424 nigel 75 \eC- do not supply a callout function
425     .\" JOIN
426     \eC!n return 1 instead of 0 when callout number n is
427 nigel 63 reached
428 nigel 75 .\" JOIN
429     \eC!n!m return 1 instead of 0 when callout number n is
430 nigel 63 reached for the nth time
431 nigel 75 .\" JOIN
432     \eC*n pass the number n (may be negative) as callout
433     data; this is used as the callout return value
434 nigel 77 \eD use the \fBpcre_dfa_exec()\fP match function
435     \eF only shortest match for \fBpcre_dfa_exec()\fP
436 nigel 75 .\" JOIN
437     \eGdd call pcre_get_substring() for substring dd
438     after a successful match (number less than 32)
439     .\" JOIN
440     \eGname call pcre_get_named_substring() for substring
441 nigel 63 "name" after a successful match (name termin-
442     ated by next non-alphanumeric character)
443 nigel 75 .\" JOIN
444 ph10 678 \eJdd set up a JIT stack of dd kilobytes maximum (any
445 ph10 691 number of digits)
446 ph10 678 .\" JOIN
447 nigel 75 \eL call pcre_get_substringlist() after a
448 nigel 63 successful match
449 nigel 91 .\" JOIN
450 nigel 87 \eM discover the minimum MATCH_LIMIT and
451     MATCH_LIMIT_RECURSION settings
452 nigel 91 .\" JOIN
453 nigel 75 \eN pass the PCRE_NOTEMPTY option to \fBpcre_exec()\fP
454 ph10 442 or \fBpcre_dfa_exec()\fP; if used twice, pass the
455 ph10 461 PCRE_NOTEMPTY_ATSTART option
456 nigel 75 .\" JOIN
457     \eOdd set the size of the output vector passed to
458     \fBpcre_exec()\fP to dd (any number of digits)
459 nigel 77 .\" JOIN
460 ph10 428 \eP pass the PCRE_PARTIAL_SOFT option to \fBpcre_exec()\fP
461     or \fBpcre_dfa_exec()\fP; if used twice, pass the
462 ph10 461 PCRE_PARTIAL_HARD option
463 nigel 91 .\" JOIN
464     \eQdd set the PCRE_MATCH_LIMIT_RECURSION limit to dd
465     (any number of digits)
466 nigel 77 \eR pass the PCRE_DFA_RESTART option to \fBpcre_dfa_exec()\fP
467 nigel 75 \eS output details of memory get/free calls during matching
468 nigel 91 .\" JOIN
469 ph10 455 \eY pass the PCRE_NO_START_OPTIMIZE option to \fBpcre_exec()\fP
470     or \fBpcre_dfa_exec()\fP
471     .\" JOIN
472 nigel 75 \eZ pass the PCRE_NOTEOL option to \fBpcre_exec()\fP
473 nigel 91 or \fBpcre_dfa_exec()\fP
474 nigel 75 .\" JOIN
475     \e? pass the PCRE_NO_UTF8_CHECK option to
476 nigel 91 \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP
477     .\" JOIN
478 ph10 567 \e>dd start the match at offset dd (optional "-"; then
479 ph10 579 any number of digits); this sets the \fIstartoffset\fP
480 ph10 567 argument for \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP
481 nigel 91 .\" JOIN
482     \e<cr> pass the PCRE_NEWLINE_CR option to \fBpcre_exec()\fP
483     or \fBpcre_dfa_exec()\fP
484     .\" JOIN
485     \e<lf> pass the PCRE_NEWLINE_LF option to \fBpcre_exec()\fP
486     or \fBpcre_dfa_exec()\fP
487     .\" JOIN
488     \e<crlf> pass the PCRE_NEWLINE_CRLF option to \fBpcre_exec()\fP
489     or \fBpcre_dfa_exec()\fP
490 nigel 93 .\" JOIN
491 ph10 149 \e<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to \fBpcre_exec()\fP
492     or \fBpcre_dfa_exec()\fP
493     .\" JOIN
494 nigel 93 \e<any> pass the PCRE_NEWLINE_ANY option to \fBpcre_exec()\fP
495     or \fBpcre_dfa_exec()\fP
496 nigel 75 .sp
497 ph10 579 Note that \exhh always specifies one byte, even in UTF-8 mode; this makes it
498     possible to construct invalid UTF-8 sequences for testing purposes. On the
499 ph10 570 other hand, \ex{hh} is interpreted as a UTF-8 character in UTF-8 mode,
500 ph10 579 generating more than one byte if the value is greater than 127. When not in
501     UTF-8 mode, it generates one byte for values less than 256, and causes an error
502 ph10 570 for greater values.
503     .P
504 nigel 93 The escapes that specify line ending sequences are literal strings, exactly as
505     shown. No more than one newline setting should be present in any data line.
506 nigel 75 .P
507 nigel 93 A backslash followed by anything else just escapes the anything else. If
508     the very last character is a backslash, it is ignored. This gives a way of
509     passing an empty line as data, since a real empty line terminates the data
510     input.
511     .P
512 ph10 678 The \fB\eJ\fP escape provides a way of setting the maximum stack size that is
513 ph10 691 used by the just-in-time optimization code. It is ignored if JIT optimization
514     is not being used. Providing a stack that is larger than the default 32K is
515 ph10 678 necessary only for very complicated patterns.
516     .P
517 nigel 75 If \eM is present, \fBpcretest\fP calls \fBpcre_exec()\fP several times, with
518 nigel 87 different values in the \fImatch_limit\fP and \fImatch_limit_recursion\fP
519     fields of the \fBpcre_extra\fP data structure, until it finds the minimum
520 ph10 691 numbers for each parameter that allow \fBpcre_exec()\fP to complete without
521     error. Because this is testing a specific feature of the normal interpretive
522     \fBpcre_exec()\fP execution, the use of any JIT optimization that might have
523 ph10 678 been set up by the \fB/S+\fP qualifier of \fB-s+\fP option is disabled.
524 nigel 75 .P
525 ph10 678 The \fImatch_limit\fP number is a measure of the amount of backtracking
526     that takes place, and checking it out can be instructive. For most simple
527     matches, the number is quite small, but for patterns with very large numbers of
528     matching possibilities, it can become large very quickly with increasing length
529     of subject string. The \fImatch_limit_recursion\fP number is a measure of how
530     much stack (or, if PCRE is compiled with NO_RECURSE, how much heap) memory is
531     needed to complete the match attempt.
532     .P
533 nigel 75 When \eO is used, the value specified may be higher or lower than the size set
534     by the \fB-O\fP command line option (or defaulted to 45); \eO applies only to
535     the call of \fBpcre_exec()\fP for the line in which it appears.
536     .P
537     If the \fB/P\fP modifier was present on the pattern, causing the POSIX wrapper
538 ph10 518 API to be used, the only option-setting sequences that have any effect are \eB,
539     \eN, and \eZ, causing REG_NOTBOL, REG_NOTEMPTY, and REG_NOTEOL, respectively,
540     to be passed to \fBregexec()\fP.
541 nigel 75 .P
542     The use of \ex{hh...} to represent UTF-8 characters is not dependent on the use
543     of the \fB/8\fP modifier on the pattern. It is recognized always. There may be
544 nigel 53 any number of hexadecimal digits inside the braces. The result is from one to
545 ph10 211 six bytes, encoded according to the original UTF-8 rules of RFC 2279. This
546     allows for values in the range 0 to 0x7FFFFFFF. Note that not all of those are
547     valid Unicode code points, or indeed valid UTF-8 characters according to the
548     later rules in RFC 3629.
549 nigel 75 .
550     .
551 nigel 77 .SH "THE ALTERNATIVE MATCHING FUNCTION"
552 nigel 63 .rs
553     .sp
554 nigel 77 By default, \fBpcretest\fP uses the standard PCRE matching function,
555     \fBpcre_exec()\fP to match each data line. From release 6.0, PCRE supports an
556     alternative matching function, \fBpcre_dfa_test()\fP, which operates in a
557     different way, and has some restrictions. The differences between the two
558     functions are described in the
559     .\" HREF
560     \fBpcrematching\fP
561     .\"
562     documentation.
563     .P
564     If a data line contains the \eD escape sequence, or if the command line
565     contains the \fB-dfa\fP option, the alternative matching function is called.
566     This function finds all possible matches at a given point. If, however, the \eF
567     escape sequence is present in the data line, it stops after the first match is
568     found. This is always the shortest possible match.
569     .
570     .
571     .SH "DEFAULT OUTPUT FROM PCRETEST"
572     .rs
573     .sp
574     This section describes the output when the normal matching function,
575     \fBpcre_exec()\fP, is being used.
576     .P
577 ph10 598 When a match succeeds, \fBpcretest\fP outputs the list of captured substrings
578     that \fBpcre_exec()\fP returns, starting with number 0 for the string that
579     matched the whole pattern. Otherwise, it outputs "No match" when the return is
580 ph10 435 PCRE_ERROR_NOMATCH, and "Partial match:" followed by the partially matching
581 ph10 553 substring when \fBpcre_exec()\fP returns PCRE_ERROR_PARTIAL. (Note that this is
582     the entire substring that was inspected during the partial match; it may
583     include characters before the actual match start if a lookbehind assertion,
584 ph10 598 \eK, \eb, or \eB was involved.) For any other return, \fBpcretest\fP outputs
585     the PCRE negative error number and a short descriptive phrase. If the error is
586     a failed UTF-8 string check, the byte offset of the start of the failing
587 ph10 654 character and the reason code are also output, provided that the size of the
588 ph10 598 output vector is at least two. Here is an example of an interactive
589     \fBpcretest\fP run.
590 nigel 75 .sp
591 nigel 53 $ pcretest
592 ph10 598 PCRE version 8.13 2011-04-30
593 nigel 75 .sp
594     re> /^abc(\ed+)/
595 nigel 53 data> abc123
596     0: abc123
597     1: 123
598     data> xyz
599     No match
600 nigel 75 .sp
601 ph10 598 Unset capturing substrings that are not followed by one that is set are not
602     returned by \fBpcre_exec()\fP, and are not shown by \fBpcretest\fP. In the
603     following example, there are two capturing substrings, but when the first data
604     line is matched, the second, unset substring is not shown. An "internal" unset
605     substring is shown as "<unset>", as for the second data line.
606 ph10 273 .sp
607     re> /(a)|(b)/
608     data> a
609     0: a
610     1: a
611     data> b
612     0: b
613     1: <unset>
614 ph10 286 2: b
615 ph10 273 .sp
616 nigel 75 If the strings contain any non-printing characters, they are output as \e0x
617     escapes, or as \ex{...} escapes if the \fB/8\fP modifier was present on the
618 nigel 93 pattern. See below for the definition of non-printing characters. If the
619     pattern has the \fB/+\fP modifier, the output for substring 0 is followed by
620     the the rest of the subject string, identified by "0+" like this:
621 nigel 75 .sp
622 nigel 53 re> /cat/+
623     data> cataract
624     0: cat
625     0+ aract
626 nigel 75 .sp
627     If the pattern has the \fB/g\fP or \fB/G\fP modifier, the results of successive
628 nigel 53 matching attempts are output in sequence, like this:
629 nigel 75 .sp
630     re> /\eBi(\ew\ew)/g
631 nigel 53 data> Mississippi
632     0: iss
633     1: ss
634     0: iss
635     1: ss
636     0: ipp
637     1: pp
638 nigel 75 .sp
639 ph10 654 "No match" is output only if the first match attempt fails. Here is an example
640     of a failure message (the offset 4 that is specified by \e>4 is past the end of
641 ph10 598 the subject string):
642     .sp
643     re> /xyz/
644 ph10 654 data> xyz\e>4
645     Error -24 (bad offset value)
646 nigel 75 .P
647     If any of the sequences \fB\eC\fP, \fB\eG\fP, or \fB\eL\fP are present in a
648 nigel 53 data line that is successfully matched, the substrings extracted by the
649     convenience functions are output with C, G, or L after the string number
650     instead of a colon. This is in addition to the normal full list. The string
651     length (that is, the return from the extraction function) is given in
652 nigel 75 parentheses after each string for \fB\eC\fP and \fB\eG\fP.
653     .P
654 nigel 93 Note that whereas patterns can be continued over several lines (a plain ">"
655 nigel 53 prompt is used for continuations), data lines may not. However newlines can be
656 nigel 93 included in data by means of the \en escape (or \er, \er\en, etc., depending on
657     the newline sequence setting).
658 nigel 75 .
659     .
660 nigel 93 .
661 nigel 77 .SH "OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION"
662     .rs
663     .sp
664     When the alternative matching function, \fBpcre_dfa_exec()\fP, is used (by
665     means of the \eD escape sequence or the \fB-dfa\fP command line option), the
666     output consists of a list of all the matches that start at the first point in
667     the subject where there is at least one match. For example:
668     .sp
669     re> /(tang|tangerine|tan)/
670     data> yellow tangerine\eD
671     0: tangerine
672     1: tang
673     2: tan
674     .sp
675     (Using the normal matching function on this data finds only "tang".) The
676 ph10 428 longest matching string is always given first (and numbered zero). After a
677 ph10 461 PCRE_ERROR_PARTIAL return, the output is "Partial match:", followed by the
678 ph10 553 partially matching substring. (Note that this is the entire substring that was
679     inspected during the partial match; it may include characters before the actual
680     match start if a lookbehind assertion, \eK, \eb, or \eB was involved.)
681 nigel 77 .P
682 nigel 93 If \fB/g\fP is present on the pattern, the search for further matches resumes
683 nigel 77 at the end of the longest match. For example:
684     .sp
685     re> /(tang|tangerine|tan)/g
686     data> yellow tangerine and tangy sultana\eD
687     0: tangerine
688     1: tang
689     2: tan
690     0: tang
691     1: tan
692     0: tan
693     .sp
694     Since the matching function does not support substring capture, the escape
695     sequences that are concerned with captured substrings are not relevant.
696     .
697     .
698     .SH "RESTARTING AFTER A PARTIAL MATCH"
699     .rs
700     .sp
701     When the alternative matching function has given the PCRE_ERROR_PARTIAL return,
702     indicating that the subject partially matched the pattern, you can restart the
703     match with additional subject data by means of the \eR escape sequence. For
704     example:
705     .sp
706 ph10 155 re> /^\ed?\ed(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\ed\ed$/
707 nigel 77 data> 23ja\eP\eD
708     Partial match: 23ja
709     data> n05\eR\eD
710     0: n05
711     .sp
712     For further information about partial matching, see the
713     .\" HREF
714     \fBpcrepartial\fP
715     .\"
716     documentation.
717     .
718     .
719 nigel 75 .SH CALLOUTS
720     .rs
721     .sp
722     If the pattern contains any callout requests, \fBpcretest\fP's callout function
723 nigel 77 is called during matching. This works with both matching functions. By default,
724     the called function displays the callout number, the start and current
725     positions in the text at the callout time, and the next pattern item to be
726     tested. For example, the output
727 nigel 75 .sp
728     --->pqrabcdef
729     0 ^ ^ \ed
730     .sp
731     indicates that callout number 0 occurred for a match attempt starting at the
732     fourth character of the subject string, when the pointer was at the seventh
733     character of the data, and when the next pattern item was \ed. Just one
734     circumflex is output if the start and current positions are the same.
735     .P
736     Callouts numbered 255 are assumed to be automatic callouts, inserted as a
737     result of the \fB/C\fP pattern modifier. In this case, instead of showing the
738     callout number, the offset in the pattern, preceded by a plus, is output. For
739     example:
740     .sp
741     re> /\ed?[A-E]\e*/C
742     data> E*
743     --->E*
744     +0 ^ \ed?
745     +3 ^ [A-E]
746     +8 ^^ \e*
747     +10 ^ ^
748     0: E*
749     .sp
750 ph10 647 If a pattern contains (*MARK) items, an additional line is output whenever
751     a change of latest mark is passed to the callout function. For example:
752     .sp
753     re> /a(*MARK:X)bc/C
754     data> abc
755     --->abc
756     +0 ^ a
757     +1 ^^ (*MARK:X)
758     +10 ^^ b
759     Latest Mark: X
760     +11 ^ ^ c
761 ph10 654 +12 ^ ^
762 ph10 647 0: abc
763     .sp
764     The mark changes between matching "a" and "b", but stays the same for the rest
765     of the match, so nothing more is output. If, as a result of backtracking, the
766     mark reverts to being unset, the text "<unset>" is output.
767     .P
768 nigel 75 The callout function in \fBpcretest\fP returns zero (carry on matching) by
769 nigel 77 default, but you can use a \eC item in a data line (as described above) to
770 ph10 647 change this and other parameters of the callout.
771 nigel 75 .P
772     Inserting callouts can be helpful when using \fBpcretest\fP to check
773     complicated regular expressions. For further information about callouts, see
774     the
775     .\" HREF
776     \fBpcrecallout\fP
777     .\"
778     documentation.
779     .
780     .
781 nigel 93 .
782     .SH "NON-PRINTING CHARACTERS"
783     .rs
784     .sp
785     When \fBpcretest\fP is outputting text in the compiled version of a pattern,
786     bytes other than 32-126 are always treated as non-printing characters are are
787     therefore shown as hex escapes.
788     .P
789     When \fBpcretest\fP is outputting text that is a matched part of a subject
790     string, it behaves in the same way, unless a different locale has been set for
791     the pattern (using the \fB/L\fP modifier). In this case, the \fBisprint()\fP
792     function to distinguish printing and non-printing characters.
793     .
794     .
795     .
796 nigel 75 .SH "SAVING AND RELOADING COMPILED PATTERNS"
797     .rs
798     .sp
799     The facilities described in this section are not available when the POSIX
800 ph10 599 interface to PCRE is being used, that is, when the \fB/P\fP pattern modifier is
801 ph10 691 specified.
802 nigel 75 .P
803     When the POSIX interface is not in use, you can cause \fBpcretest\fP to write a
804     compiled pattern to a file, by following the modifiers with > and a file name.
805     For example:
806     .sp
807     /pattern/im >/some/file
808     .sp
809     See the
810     .\" HREF
811     \fBpcreprecompile\fP
812     .\"
813     documentation for a discussion about saving and re-using compiled patterns.
814 ph10 678 Note that if the pattern was successfully studied with JIT optimization, the
815     JIT data cannot be saved.
816 nigel 75 .P
817     The data that is written is binary. The first eight bytes are the length of the
818     compiled pattern data followed by the length of the optional study data, each
819     written as four bytes in big-endian order (most significant byte first). If
820     there is no study data (either the pattern was not studied, or studying did not
821     return any data), the second length is zero. The lengths are followed by an
822     exact copy of the compiled pattern. If there is additional study data, this
823 ph10 678 (excluding any JIT data) follows immediately after the compiled pattern. After
824     writing the file, \fBpcretest\fP expects to read a new pattern.
825 nigel 75 .P
826 ph10 599 A saved pattern can be reloaded into \fBpcretest\fP by specifying < and a file
827 nigel 75 name instead of a pattern. The name of the file must not contain a < character,
828     as otherwise \fBpcretest\fP will interpret the line as a pattern delimited by <
829     characters.
830     For example:
831     .sp
832     re> </some/file
833 ph10 612 Compiled pattern loaded from /some/file
834 nigel 75 No study data
835     .sp
836 ph10 678 If the pattern was previously studied with the JIT optimization, the JIT
837     information cannot be saved and restored, and so is lost. When the pattern has
838     been loaded, \fBpcretest\fP proceeds to read data lines in the usual way.
839 nigel 75 .P
840     You can copy a file written by \fBpcretest\fP to a different host and reload it
841     there, even if the new host has opposite endianness to the one on which the
842     pattern was compiled. For example, you can compile on an i86 machine and run on
843     a SPARC machine.
844     .P
845     File names for saving and reloading can be absolute or relative, but note that
846     the shell facility of expanding a file name that starts with a tilde (~) is not
847     available.
848     .P
849     The ability to save and reload files in \fBpcretest\fP is intended for testing
850     and experimentation. It is not intended for production use because only a
851     single pattern can be written to a file. Furthermore, there is no facility for
852     supplying custom character tables for use with a reloaded pattern. If the
853     original pattern was compiled with custom tables, an attempt to match a subject
854     string using a reloaded pattern is likely to cause \fBpcretest\fP to crash.
855     Finally, if you attempt to load a file that is not in the correct format, the
856     result is undefined.
857     .
858     .
859 nigel 93 .SH "SEE ALSO"
860     .rs
861     .sp
862 ph10 678 \fBpcre\fP(3), \fBpcreapi\fP(3), \fBpcrecallout\fP(3), \fBpcrejit\fP,
863     \fBpcrematching\fP(3), \fBpcrepartial\fP(d), \fBpcrepattern\fP(3),
864     \fBpcreprecompile\fP(3).
865 nigel 93 .
866     .
867 nigel 53 .SH AUTHOR
868 nigel 63 .rs
869     .sp
870 ph10 99 .nf
871 nigel 77 Philip Hazel
872 ph10 99 University Computing Service
873 nigel 93 Cambridge CB2 3QH, England.
874 ph10 99 .fi
875     .
876     .
877     .SH REVISION
878     .rs
879     .sp
880     .nf
881 ph10 780 Last updated: 02 December 2011
882 ph10 598 Copyright (c) 1997-2011 University of Cambridge.
883 ph10 99 .fi

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