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1 | This file contains the PCRE man page that described the pcretest program. Note |
2 | that not all of the features of PCRE are available in the limited version that | |
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3 | is built with Exim. |
4 | ------------------------------------------------------------------------------- | |
5 | ||
6 | PCRETEST(1) PCRETEST(1) | |
7 | ||
8 | ||
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9 | NAME |
10 | pcretest - a program for testing Perl-compatible regular expressions. | |
11 | ||
92e772ff | 12 | |
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13 | SYNOPSIS |
14 | ||
8ac170f3 | 15 | pcretest [-C] [-d] [-dfa] [-i] [-m] [-o osize] [-p] [-t] [source] |
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16 | [destination] |
17 | ||
18 | pcretest was written as a test program for the PCRE regular expression | |
19 | library itself, but it can also be used for experimenting with regular | |
20 | expressions. This document describes the features of the test program; | |
21 | for details of the regular expressions themselves, see the pcrepattern | |
22 | documentation. For details of the PCRE library function calls and their | |
23 | options, see the pcreapi documentation. | |
24 | ||
25 | ||
26 | OPTIONS | |
27 | ||
28 | -C Output the version number of the PCRE library, and all avail- | |
29 | able information about the optional features that are | |
30 | included, and then exit. | |
31 | ||
8ac170f3 | 32 | -d Behave as if each regex has the /D (debug) modifier; the |
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33 | internal form is output after compilation. |
34 | ||
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35 | -dfa Behave as if each data line contains the \D escape sequence; |
36 | this causes the alternative matching function, | |
37 | pcre_dfa_exec(), to be used instead of the standard | |
38 | pcre_exec() function (more detail is given below). | |
39 | ||
40 | -i Behave as if each regex has the /I modifier; information | |
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41 | about the compiled pattern is given after compilation. |
42 | ||
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43 | -m Output the size of each compiled pattern after it has been |
44 | compiled. This is equivalent to adding /M to each regular | |
45 | expression. For compatibility with earlier versions of | |
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46 | pcretest, -s is a synonym for -m. |
47 | ||
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48 | -o osize Set the number of elements in the output vector that is used |
49 | when calling pcre_exec() to be osize. The default value is | |
495ae4b0 | 50 | 45, which is enough for 14 capturing subexpressions. The vec- |
8ac170f3 | 51 | tor size can be changed for individual matching calls by |
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52 | including \O in the data line (see below). |
53 | ||
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54 | -p Behave as if each regex has the /P modifier; the POSIX wrap- |
55 | per API is used to call PCRE. None of the other options has | |
56 | any effect when -p is set. | |
495ae4b0 | 57 | |
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58 | -t Run each compile, study, and match many times with a timer, |
59 | and output resulting time per compile or match (in millisec- | |
60 | onds). Do not set -m with -t, because you will then get the | |
61 | size output a zillion times, and the timing will be dis- | |
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62 | torted. |
63 | ||
64 | ||
65 | DESCRIPTION | |
66 | ||
8ac170f3 | 67 | If pcretest is given two filename arguments, it reads from the first |
495ae4b0 | 68 | and writes to the second. If it is given only one filename argument, it |
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69 | reads from that file and writes to stdout. Otherwise, it reads from |
70 | stdin and writes to stdout, and prompts for each line of input, using | |
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71 | "re>" to prompt for regular expressions, and "data>" to prompt for data |
72 | lines. | |
73 | ||
74 | The program handles any number of sets of input on a single input file. | |
8ac170f3 | 75 | Each set starts with a regular expression, and continues with any num- |
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76 | ber of data lines to be matched against the pattern. |
77 | ||
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78 | Each data line is matched separately and independently. If you want to |
79 | do multiple-line matches, you have to use the \n escape sequence in a | |
80 | single line of input to encode the newline characters. The maximum | |
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81 | length of data line is 30,000 characters. |
82 | ||
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83 | An empty line signals the end of the data lines, at which point a new |
84 | regular expression is read. The regular expressions are given enclosed | |
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85 | in any non-alphanumeric delimiters other than backslash, for example |
86 | ||
87 | /(a|bc)x+yz/ | |
88 | ||
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89 | White space before the initial delimiter is ignored. A regular expres- |
90 | sion may be continued over several input lines, in which case the new- | |
91 | line characters are included within it. It is possible to include the | |
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92 | delimiter within the pattern by escaping it, for example |
93 | ||
94 | /abc\/def/ | |
95 | ||
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96 | If you do so, the escape and the delimiter form part of the pattern, |
97 | but since delimiters are always non-alphanumeric, this does not affect | |
98 | its interpretation. If the terminating delimiter is immediately fol- | |
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99 | lowed by a backslash, for example, |
100 | ||
101 | /abc/\ | |
102 | ||
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103 | then a backslash is added to the end of the pattern. This is done to |
104 | provide a way of testing the error condition that arises if a pattern | |
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105 | finishes with a backslash, because |
106 | ||
107 | /abc\/ | |
108 | ||
8ac170f3 | 109 | is interpreted as the first line of a pattern that starts with "abc/", |
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110 | causing pcretest to read the next line as a continuation of the regular |
111 | expression. | |
112 | ||
113 | ||
114 | PATTERN MODIFIERS | |
115 | ||
8ac170f3 PH |
116 | A pattern may be followed by any number of modifiers, which are mostly |
117 | single characters. Following Perl usage, these are referred to below | |
118 | as, for example, "the /i modifier", even though the delimiter of the | |
119 | pattern need not always be a slash, and no slash is used when writing | |
120 | modifiers. Whitespace may appear between the final pattern delimiter | |
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121 | and the first modifier, and between the modifiers themselves. |
122 | ||
123 | The /i, /m, /s, and /x modifiers set the PCRE_CASELESS, PCRE_MULTILINE, | |
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124 | PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when pcre_com- |
125 | pile() is called. These four modifier letters have the same effect as | |
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126 | they do in Perl. For example: |
127 | ||
128 | /caseless/i | |
129 | ||
130 | The following table shows additional modifiers for setting PCRE options | |
131 | that do not correspond to anything in Perl: | |
132 | ||
133 | /A PCRE_ANCHORED | |
134 | /C PCRE_AUTO_CALLOUT | |
135 | /E PCRE_DOLLAR_ENDONLY | |
8ac170f3 | 136 | /f PCRE_FIRSTLINE |
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137 | /N PCRE_NO_AUTO_CAPTURE |
138 | /U PCRE_UNGREEDY | |
139 | /X PCRE_EXTRA | |
140 | ||
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141 | Searching for all possible matches within each subject string can be |
142 | requested by the /g or /G modifier. After finding a match, PCRE is | |
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143 | called again to search the remainder of the subject string. The differ- |
144 | ence between /g and /G is that the former uses the startoffset argument | |
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145 | to pcre_exec() to start searching at a new point within the entire |
146 | string (which is in effect what Perl does), whereas the latter passes | |
147 | over a shortened substring. This makes a difference to the matching | |
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148 | process if the pattern begins with a lookbehind assertion (including \b |
149 | or \B). | |
150 | ||
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151 | If any call to pcre_exec() in a /g or /G sequence matches an empty |
152 | string, the next call is done with the PCRE_NOTEMPTY and PCRE_ANCHORED | |
153 | flags set in order to search for another, non-empty, match at the same | |
154 | point. If this second match fails, the start offset is advanced by | |
155 | one, and the normal match is retried. This imitates the way Perl han- | |
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156 | dles such cases when using the /g modifier or the split() function. |
157 | ||
158 | There are yet more modifiers for controlling the way pcretest operates. | |
159 | ||
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160 | The /+ modifier requests that as well as outputting the substring that |
161 | matched the entire pattern, pcretest should in addition output the | |
162 | remainder of the subject string. This is useful for tests where the | |
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163 | subject contains multiple copies of the same substring. |
164 | ||
8ac170f3 | 165 | The /L modifier must be followed directly by the name of a locale, for |
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166 | example, |
167 | ||
168 | /pattern/Lfr_FR | |
169 | ||
170 | For this reason, it must be the last modifier. The given locale is set, | |
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171 | pcre_maketables() is called to build a set of character tables for the |
172 | locale, and this is then passed to pcre_compile() when compiling the | |
173 | regular expression. Without an /L modifier, NULL is passed as the | |
174 | tables pointer; that is, /L applies only to the expression on which it | |
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175 | appears. |
176 | ||
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177 | The /I modifier requests that pcretest output information about the |
178 | compiled pattern (whether it is anchored, has a fixed first character, | |
179 | and so on). It does this by calling pcre_fullinfo() after compiling a | |
180 | pattern. If the pattern is studied, the results of that are also out- | |
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181 | put. |
182 | ||
183 | The /D modifier is a PCRE debugging feature, which also assumes /I. It | |
8ac170f3 | 184 | causes the internal form of compiled regular expressions to be output |
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185 | after compilation. If the pattern was studied, the information returned |
186 | is also output. | |
187 | ||
188 | The /F modifier causes pcretest to flip the byte order of the fields in | |
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189 | the compiled pattern that contain 2-byte and 4-byte numbers. This |
190 | facility is for testing the feature in PCRE that allows it to execute | |
495ae4b0 | 191 | patterns that were compiled on a host with a different endianness. This |
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192 | feature is not available when the POSIX interface to PCRE is being |
193 | used, that is, when the /P pattern modifier is specified. See also the | |
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194 | section about saving and reloading compiled patterns below. |
195 | ||
8ac170f3 | 196 | The /S modifier causes pcre_study() to be called after the expression |
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197 | has been compiled, and the results used when the expression is matched. |
198 | ||
8ac170f3 | 199 | The /M modifier causes the size of memory block used to hold the com- |
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200 | piled pattern to be output. |
201 | ||
8ac170f3 PH |
202 | The /P modifier causes pcretest to call PCRE via the POSIX wrapper API |
203 | rather than its native API. When this is done, all other modifiers | |
204 | except /i, /m, and /+ are ignored. REG_ICASE is set if /i is present, | |
205 | and REG_NEWLINE is set if /m is present. The wrapper functions force | |
206 | PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless REG_NEWLINE is set. | |
495ae4b0 | 207 | |
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208 | The /8 modifier causes pcretest to call PCRE with the PCRE_UTF8 option |
209 | set. This turns on support for UTF-8 character handling in PCRE, pro- | |
210 | vided that it was compiled with this support enabled. This modifier | |
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211 | also causes any non-printing characters in output strings to be printed |
212 | using the \x{hh...} notation if they are valid UTF-8 sequences. | |
213 | ||
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214 | If the /? modifier is used with /8, it causes pcretest to call |
215 | pcre_compile() with the PCRE_NO_UTF8_CHECK option, to suppress the | |
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216 | checking of the string for UTF-8 validity. |
217 | ||
218 | ||
219 | DATA LINES | |
220 | ||
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221 | Before each data line is passed to pcre_exec(), leading and trailing |
222 | whitespace is removed, and it is then scanned for \ escapes. Some of | |
223 | these are pretty esoteric features, intended for checking out some of | |
224 | the more complicated features of PCRE. If you are just testing "ordi- | |
225 | nary" regular expressions, you probably don't need any of these. The | |
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226 | following escapes are recognized: |
227 | ||
228 | \a alarm (= BEL) | |
229 | \b backspace | |
230 | \e escape | |
231 | \f formfeed | |
232 | \n newline | |
233 | \r carriage return | |
234 | \t tab | |
235 | \v vertical tab | |
236 | \nnn octal character (up to 3 octal digits) | |
237 | \xhh hexadecimal character (up to 2 hex digits) | |
238 | \x{hh...} hexadecimal character, any number of digits | |
239 | in UTF-8 mode | |
240 | \A pass the PCRE_ANCHORED option to pcre_exec() | |
241 | \B pass the PCRE_NOTBOL option to pcre_exec() | |
242 | \Cdd call pcre_copy_substring() for substring dd | |
243 | after a successful match (number less than 32) | |
244 | \Cname call pcre_copy_named_substring() for substring | |
245 | "name" after a successful match (name termin- | |
246 | ated by next non alphanumeric character) | |
247 | \C+ show the current captured substrings at callout | |
248 | time | |
249 | \C- do not supply a callout function | |
250 | \C!n return 1 instead of 0 when callout number n is | |
251 | reached | |
252 | \C!n!m return 1 instead of 0 when callout number n is | |
253 | reached for the nth time | |
254 | \C*n pass the number n (may be negative) as callout | |
255 | data; this is used as the callout return value | |
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256 | \D use the pcre_dfa_exec() match function |
257 | \F only shortest match for pcre_dfa_exec() | |
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258 | \Gdd call pcre_get_substring() for substring dd |
259 | after a successful match (number less than 32) | |
260 | \Gname call pcre_get_named_substring() for substring | |
261 | "name" after a successful match (name termin- | |
262 | ated by next non-alphanumeric character) | |
263 | \L call pcre_get_substringlist() after a | |
264 | successful match | |
265 | \M discover the minimum MATCH_LIMIT setting | |
266 | \N pass the PCRE_NOTEMPTY option to pcre_exec() | |
267 | \Odd set the size of the output vector passed to | |
268 | pcre_exec() to dd (any number of digits) | |
269 | \P pass the PCRE_PARTIAL option to pcre_exec() | |
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270 | or pcre_dfa_exec() |
271 | \R pass the PCRE_DFA_RESTART option to pcre_dfa_exec() | |
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272 | \S output details of memory get/free calls during matching |
273 | \Z pass the PCRE_NOTEOL option to pcre_exec() | |
274 | \? pass the PCRE_NO_UTF8_CHECK option to | |
275 | pcre_exec() | |
276 | \>dd start the match at offset dd (any number of digits); | |
277 | this sets the startoffset argument for pcre_exec() | |
278 | ||
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279 | A backslash followed by anything else just escapes the anything else. |
280 | If the very last character is a backslash, it is ignored. This gives a | |
281 | way of passing an empty line as data, since a real empty line termi- | |
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282 | nates the data input. |
283 | ||
8ac170f3 PH |
284 | If \M is present, pcretest calls pcre_exec() several times, with dif- |
285 | ferent values in the match_limit field of the pcre_extra data struc- | |
286 | ture, until it finds the minimum number that is needed for pcre_exec() | |
287 | to complete. This number is a measure of the amount of recursion and | |
288 | backtracking that takes place, and checking it out can be instructive. | |
289 | For most simple matches, the number is quite small, but for patterns | |
290 | with very large numbers of matching possibilities, it can become large | |
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291 | very quickly with increasing length of subject string. |
292 | ||
8ac170f3 | 293 | When \O is used, the value specified may be higher or lower than the |
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294 | size set by the -O command line option (or defaulted to 45); \O applies |
295 | only to the call of pcre_exec() for the line in which it appears. | |
296 | ||
8ac170f3 PH |
297 | If the /P modifier was present on the pattern, causing the POSIX wrap- |
298 | per API to be used, only \B and \Z have any effect, causing REG_NOTBOL | |
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299 | and REG_NOTEOL to be passed to regexec() respectively. |
300 | ||
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301 | The use of \x{hh...} to represent UTF-8 characters is not dependent on |
302 | the use of the /8 modifier on the pattern. It is recognized always. | |
303 | There may be any number of hexadecimal digits inside the braces. The | |
304 | result is from one to six bytes, encoded according to the UTF-8 rules. | |
305 | ||
306 | ||
307 | THE ALTERNATIVE MATCHING FUNCTION | |
308 | ||
309 | By default, pcretest uses the standard PCRE matching function, | |
310 | pcre_exec() to match each data line. From release 6.0, PCRE supports an | |
311 | alternative matching function, pcre_dfa_test(), which operates in a | |
312 | different way, and has some restrictions. The differences between the | |
313 | two functions are described in the pcrematching documentation. | |
314 | ||
315 | If a data line contains the \D escape sequence, or if the command line | |
316 | contains the -dfa option, the alternative matching function is called. | |
317 | This function finds all possible matches at a given point. If, however, | |
318 | the \F escape sequence is present in the data line, it stops after the | |
319 | first match is found. This is always the shortest possible match. | |
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320 | |
321 | ||
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322 | DEFAULT OUTPUT FROM PCRETEST |
323 | ||
324 | This section describes the output when the normal matching function, | |
325 | pcre_exec(), is being used. | |
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326 | |
327 | When a match succeeds, pcretest outputs the list of captured substrings | |
328 | that pcre_exec() returns, starting with number 0 for the string that | |
329 | matched the whole pattern. Otherwise, it outputs "No match" or "Partial | |
330 | match" when pcre_exec() returns PCRE_ERROR_NOMATCH or PCRE_ERROR_PAR- | |
331 | TIAL, respectively, and otherwise the PCRE negative error number. Here | |
332 | is an example of an interactive pcretest run. | |
333 | ||
334 | $ pcretest | |
335 | PCRE version 5.00 07-Sep-2004 | |
336 | ||
337 | re> /^abc(\d+)/ | |
338 | data> abc123 | |
339 | 0: abc123 | |
340 | 1: 123 | |
341 | data> xyz | |
342 | No match | |
343 | ||
344 | If the strings contain any non-printing characters, they are output as | |
345 | \0x escapes, or as \x{...} escapes if the /8 modifier was present on | |
346 | the pattern. If the pattern has the /+ modifier, the output for sub- | |
347 | string 0 is followed by the the rest of the subject string, identified | |
348 | by "0+" like this: | |
349 | ||
350 | re> /cat/+ | |
351 | data> cataract | |
352 | 0: cat | |
353 | 0+ aract | |
354 | ||
355 | If the pattern has the /g or /G modifier, the results of successive | |
356 | matching attempts are output in sequence, like this: | |
357 | ||
358 | re> /\Bi(\w\w)/g | |
359 | data> Mississippi | |
360 | 0: iss | |
361 | 1: ss | |
362 | 0: iss | |
363 | 1: ss | |
364 | 0: ipp | |
365 | 1: pp | |
366 | ||
367 | "No match" is output only if the first match attempt fails. | |
368 | ||
369 | If any of the sequences \C, \G, or \L are present in a data line that | |
370 | is successfully matched, the substrings extracted by the convenience | |
371 | functions are output with C, G, or L after the string number instead of | |
372 | a colon. This is in addition to the normal full list. The string length | |
373 | (that is, the return from the extraction function) is given in paren- | |
374 | theses after each string for \C and \G. | |
375 | ||
376 | Note that while patterns can be continued over several lines (a plain | |
377 | ">" prompt is used for continuations), data lines may not. However new- | |
378 | lines can be included in data by means of the \n escape. | |
379 | ||
380 | ||
8ac170f3 PH |
381 | OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION |
382 | ||
383 | When the alternative matching function, pcre_dfa_exec(), is used (by | |
384 | means of the \D escape sequence or the -dfa command line option), the | |
385 | output consists of a list of all the matches that start at the first | |
386 | point in the subject where there is at least one match. For example: | |
387 | ||
388 | re> /(tang|tangerine|tan)/ | |
389 | data> yellow tangerine\D | |
390 | 0: tangerine | |
391 | 1: tang | |
392 | 2: tan | |
393 | ||
394 | (Using the normal matching function on this data finds only "tang".) | |
395 | The longest matching string is always given first (and numbered zero). | |
396 | ||
397 | If /gP is present on the pattern, the search for further matches | |
398 | resumes at the end of the longest match. For example: | |
399 | ||
400 | re> /(tang|tangerine|tan)/g | |
401 | data> yellow tangerine and tangy sultana\D | |
402 | 0: tangerine | |
403 | 1: tang | |
404 | 2: tan | |
405 | 0: tang | |
406 | 1: tan | |
407 | 0: tan | |
408 | ||
409 | Since the matching function does not support substring capture, the | |
410 | escape sequences that are concerned with captured substrings are not | |
411 | relevant. | |
412 | ||
413 | ||
414 | RESTARTING AFTER A PARTIAL MATCH | |
415 | ||
416 | When the alternative matching function has given the PCRE_ERROR_PARTIAL | |
417 | return, indicating that the subject partially matched the pattern, you | |
418 | can restart the match with additional subject data by means of the \R | |
419 | escape sequence. For example: | |
420 | ||
421 | re> /^?(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)$/ | |
422 | data> 23ja\P\D | |
423 | Partial match: 23ja | |
424 | data> n05\R\D | |
425 | 0: n05 | |
426 | ||
427 | For further information about partial matching, see the pcrepartial | |
428 | documentation. | |
429 | ||
430 | ||
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431 | CALLOUTS |
432 | ||
433 | If the pattern contains any callout requests, pcretest's callout func- | |
8ac170f3 PH |
434 | tion is called during matching. This works with both matching func- |
435 | tions. By default, the called function displays the callout number, the | |
436 | start and current positions in the text at the callout time, and the | |
437 | next pattern item to be tested. For example, the output | |
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438 | |
439 | --->pqrabcdef | |
440 | 0 ^ ^ \d | |
441 | ||
8ac170f3 PH |
442 | indicates that callout number 0 occurred for a match attempt starting |
443 | at the fourth character of the subject string, when the pointer was at | |
444 | the seventh character of the data, and when the next pattern item was | |
445 | \d. Just one circumflex is output if the start and current positions | |
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446 | are the same. |
447 | ||
448 | Callouts numbered 255 are assumed to be automatic callouts, inserted as | |
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449 | a result of the /C pattern modifier. In this case, instead of showing |
450 | the callout number, the offset in the pattern, preceded by a plus, is | |
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451 | output. For example: |
452 | ||
453 | re> /\d?[A-E]\*/C | |
454 | data> E* | |
455 | --->E* | |
456 | +0 ^ \d? | |
457 | +3 ^ [A-E] | |
458 | +8 ^^ \* | |
459 | +10 ^ ^ | |
460 | 0: E* | |
461 | ||
8ac170f3 PH |
462 | The callout function in pcretest returns zero (carry on matching) by |
463 | default, but you can use a \C item in a data line (as described above) | |
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464 | to change this. |
465 | ||
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466 | Inserting callouts can be helpful when using pcretest to check compli- |
467 | cated regular expressions. For further information about callouts, see | |
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468 | the pcrecallout documentation. |
469 | ||
470 | ||
471 | SAVING AND RELOADING COMPILED PATTERNS | |
472 | ||
8ac170f3 | 473 | The facilities described in this section are not available when the |
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474 | POSIX inteface to PCRE is being used, that is, when the /P pattern mod- |
475 | ifier is specified. | |
476 | ||
477 | When the POSIX interface is not in use, you can cause pcretest to write | |
8ac170f3 | 478 | a compiled pattern to a file, by following the modifiers with > and a |
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479 | file name. For example: |
480 | ||
481 | /pattern/im >/some/file | |
482 | ||
8ac170f3 | 483 | See the pcreprecompile documentation for a discussion about saving and |
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484 | re-using compiled patterns. |
485 | ||
8ac170f3 PH |
486 | The data that is written is binary. The first eight bytes are the |
487 | length of the compiled pattern data followed by the length of the | |
488 | optional study data, each written as four bytes in big-endian order | |
489 | (most significant byte first). If there is no study data (either the | |
495ae4b0 | 490 | pattern was not studied, or studying did not return any data), the sec- |
8ac170f3 | 491 | ond length is zero. The lengths are followed by an exact copy of the |
495ae4b0 | 492 | compiled pattern. If there is additional study data, this follows imme- |
8ac170f3 | 493 | diately after the compiled pattern. After writing the file, pcretest |
495ae4b0 PH |
494 | expects to read a new pattern. |
495 | ||
496 | A saved pattern can be reloaded into pcretest by specifing < and a file | |
8ac170f3 PH |
497 | name instead of a pattern. The name of the file must not contain a < |
498 | character, as otherwise pcretest will interpret the line as a pattern | |
495ae4b0 PH |
499 | delimited by < characters. For example: |
500 | ||
501 | re> </some/file | |
502 | Compiled regex loaded from /some/file | |
503 | No study data | |
504 | ||
8ac170f3 | 505 | When the pattern has been loaded, pcretest proceeds to read data lines |
495ae4b0 PH |
506 | in the usual way. |
507 | ||
8ac170f3 PH |
508 | You can copy a file written by pcretest to a different host and reload |
509 | it there, even if the new host has opposite endianness to the one on | |
510 | which the pattern was compiled. For example, you can compile on an i86 | |
495ae4b0 PH |
511 | machine and run on a SPARC machine. |
512 | ||
8ac170f3 PH |
513 | File names for saving and reloading can be absolute or relative, but |
514 | note that the shell facility of expanding a file name that starts with | |
495ae4b0 PH |
515 | a tilde (~) is not available. |
516 | ||
8ac170f3 PH |
517 | The ability to save and reload files in pcretest is intended for test- |
518 | ing and experimentation. It is not intended for production use because | |
519 | only a single pattern can be written to a file. Furthermore, there is | |
520 | no facility for supplying custom character tables for use with a | |
521 | reloaded pattern. If the original pattern was compiled with custom | |
522 | tables, an attempt to match a subject string using a reloaded pattern | |
523 | is likely to cause pcretest to crash. Finally, if you attempt to load | |
495ae4b0 PH |
524 | a file that is not in the correct format, the result is undefined. |
525 | ||
526 | ||
527 | AUTHOR | |
528 | ||
8ac170f3 | 529 | Philip Hazel |
495ae4b0 PH |
530 | University Computing Service, |
531 | Cambridge CB2 3QG, England. | |
532 | ||
8ac170f3 PH |
533 | Last updated: 28 February 2005 |
534 | Copyright (c) 1997-2005 University of Cambridge. |