1<html>
2<head>
3<title>pcretest specification</title>
4</head>
5<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
6<h1>pcretest man page</h1>
7<p>
8Return to the <a href="index.html">PCRE index page</a>.
9</p>
10<p>
11This page is part of the PCRE HTML documentation. It was generated automatically
12from the original man page. If there is any nonsense in it, please consult the
13man page, in case the conversion went wrong.
14<br>
15<ul>
16<li><a name="TOC1" href="#SEC1">SYNOPSIS</a>
17<li><a name="TOC2" href="#SEC2">INPUT DATA FORMAT</a>
18<li><a name="TOC3" href="#SEC3">PCRE's 8-BIT, 16-BIT AND 32-BIT LIBRARIES</a>
19<li><a name="TOC4" href="#SEC4">COMMAND LINE OPTIONS</a>
20<li><a name="TOC5" href="#SEC5">DESCRIPTION</a>
21<li><a name="TOC6" href="#SEC6">PATTERN MODIFIERS</a>
22<li><a name="TOC7" href="#SEC7">DATA LINES</a>
23<li><a name="TOC8" href="#SEC8">THE ALTERNATIVE MATCHING FUNCTION</a>
24<li><a name="TOC9" href="#SEC9">DEFAULT OUTPUT FROM PCRETEST</a>
25<li><a name="TOC10" href="#SEC10">OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION</a>
26<li><a name="TOC11" href="#SEC11">RESTARTING AFTER A PARTIAL MATCH</a>
27<li><a name="TOC12" href="#SEC12">CALLOUTS</a>
28<li><a name="TOC13" href="#SEC13">NON-PRINTING CHARACTERS</a>
29<li><a name="TOC14" href="#SEC14">SAVING AND RELOADING COMPILED PATTERNS</a>
30<li><a name="TOC15" href="#SEC15">SEE ALSO</a>
31<li><a name="TOC16" href="#SEC16">AUTHOR</a>
32<li><a name="TOC17" href="#SEC17">REVISION</a>
33</ul>
34<br><a name="SEC1" href="#TOC1">SYNOPSIS</a><br>
35<P>
36<b>pcretest [options] [input file [output file]]</b>
37<br>
38<br>
39<b>pcretest</b> was written as a test program for the PCRE regular expression
40library itself, but it can also be used for experimenting with regular
41expressions. This document describes the features of the test program; for
42details of the regular expressions themselves, see the
43<a href="pcrepattern.html"><b>pcrepattern</b></a>
44documentation. For details of the PCRE library function calls and their
45options, see the
46<a href="pcreapi.html"><b>pcreapi</b></a>
47,
48<a href="pcre16.html"><b>pcre16</b></a>
49and
50<a href="pcre32.html"><b>pcre32</b></a>
51documentation.
52</P>
53<P>
54The input for <b>pcretest</b> is a sequence of regular expression patterns and
55strings to be matched, as described below. The output shows the result of each
56match. Options on the command line and the patterns control PCRE options and
57exactly what is output.
58</P>
59<P>
60As PCRE has evolved, it has acquired many different features, and as a result,
61<b>pcretest</b> now has rather a lot of obscure options for testing every
62possible feature. Some of these options are specifically designed for use in
63conjunction with the test script and data files that are distributed as part of
64PCRE, and are unlikely to be of use otherwise. They are all documented here,
65but without much justification.
66</P>
67<br><a name="SEC2" href="#TOC1">INPUT DATA FORMAT</a><br>
68<P>
69Input to <b>pcretest</b> is processed line by line, either by calling the C
70library's <b>fgets()</b> function, or via the <b>libreadline</b> library (see
71below). In Unix-like environments, <b>fgets()</b> treats any bytes other than
72newline as data characters. However, in some Windows environments character 26
73(hex 1A) causes an immediate end of file, and no further data is read. For
74maximum portability, therefore, it is safest to use only ASCII characters in
75<b>pcretest</b> input files.
76</P>
77<br><a name="SEC3" href="#TOC1">PCRE's 8-BIT, 16-BIT AND 32-BIT LIBRARIES</a><br>
78<P>
79From release 8.30, two separate PCRE libraries can be built. The original one
80supports 8-bit character strings, whereas the newer 16-bit library supports
81character strings encoded in 16-bit units. From release 8.32, a third library
82can be built, supporting character strings encoded in 32-bit units. The
83<b>pcretest</b> program can be used to test all three libraries. However, it is
84itself still an 8-bit program, reading 8-bit input and writing 8-bit output.
85When testing the 16-bit or 32-bit library, the patterns and data strings are
86converted to 16- or 32-bit format before being passed to the PCRE library
87functions. Results are converted to 8-bit for output.
88</P>
89<P>
90References to functions and structures of the form <b>pcre[16|32]_xx</b> below
91mean "<b>pcre_xx</b> when using the 8-bit library, <b>pcre16_xx</b> when using
92the 16-bit library, or <b>pcre32_xx</b> when using the 32-bit library".
93</P>
94<br><a name="SEC4" href="#TOC1">COMMAND LINE OPTIONS</a><br>
95<P>
96<b>-8</b>
97If both the 8-bit library has been built, this option causes the 8-bit library
98to be used (which is the default); if the 8-bit library has not been built,
99this option causes an error.
100</P>
101<P>
102<b>-16</b>
103If both the 8-bit or the 32-bit, and the 16-bit libraries have been built, this
104option causes the 16-bit library to be used. If only the 16-bit library has been
105built, this is the default (so has no effect). If only the 8-bit or the 32-bit
106library has been built, this option causes an error.
107</P>
108<P>
109<b>-32</b>
110If both the 8-bit or the 16-bit, and the 32-bit libraries have been built, this
111option causes the 32-bit library to be used. If only the 32-bit library has been
112built, this is the default (so has no effect). If only the 8-bit or the 16-bit
113library has been built, this option causes an error.
114</P>
115<P>
116<b>-b</b>
117Behave as if each pattern has the <b>/B</b> (show byte code) modifier; the
118internal form is output after compilation.
119</P>
120<P>
121<b>-C</b>
122Output the version number of the PCRE library, and all available information
123about the optional features that are included, and then exit with zero exit
124code. All other options are ignored.
125</P>
126<P>
127<b>-C</b> <i>option</i>
128Output information about a specific build-time option, then exit. This
129functionality is intended for use in scripts such as <b>RunTest</b>. The
130following options output the value and set the exit code as indicated:
131<pre>
132  ebcdic-nl  the code for LF (= NL) in an EBCDIC environment:
133               0x15 or 0x25
134               0 if used in an ASCII environment
135               exit code is always 0
136  linksize   the configured internal link size (2, 3, or 4)
137               exit code is set to the link size
138  newline    the default newline setting:
139               CR, LF, CRLF, ANYCRLF, or ANY
140               exit code is always 0
141  bsr        the default setting for what \R matches:
142               ANYCRLF or ANY
143               exit code is always 0
144</pre>
145The following options output 1 for true or 0 for false, and set the exit code
146to the same value:
147<pre>
148  ebcdic     compiled for an EBCDIC environment
149  jit        just-in-time support is available
150  pcre16     the 16-bit library was built
151  pcre32     the 32-bit library was built
152  pcre8      the 8-bit library was built
153  ucp        Unicode property support is available
154  utf        UTF-8 and/or UTF-16 and/or UTF-32 support
155               is available
156</pre>
157If an unknown option is given, an error message is output; the exit code is 0.
158</P>
159<P>
160<b>-d</b>
161Behave as if each pattern has the <b>/D</b> (debug) modifier; the internal
162form and information about the compiled pattern is output after compilation;
163<b>-d</b> is equivalent to <b>-b -i</b>.
164</P>
165<P>
166<b>-dfa</b>
167Behave as if each data line contains the \D escape sequence; this causes the
168alternative matching function, <b>pcre[16|32]_dfa_exec()</b>, to be used instead
169of the standard <b>pcre[16|32]_exec()</b> function (more detail is given below).
170</P>
171<P>
172<b>-help</b>
173Output a brief summary these options and then exit.
174</P>
175<P>
176<b>-i</b>
177Behave as if each pattern has the <b>/I</b> modifier; information about the
178compiled pattern is given after compilation.
179</P>
180<P>
181<b>-M</b>
182Behave as if each data line contains the \M escape sequence; this causes
183PCRE to discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings by
184calling <b>pcre[16|32]_exec()</b> repeatedly with different limits.
185</P>
186<P>
187<b>-m</b>
188Output the size of each compiled pattern after it has been compiled. This is
189equivalent to adding <b>/M</b> to each regular expression. The size is given in
190bytes for both libraries.
191</P>
192<P>
193<b>-O</b>
194Behave as if each pattern has the <b>/O</b> modifier, that is disable
195auto-possessification for all patterns.
196</P>
197<P>
198<b>-o</b> <i>osize</i>
199Set the number of elements in the output vector that is used when calling
200<b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b> to be <i>osize</i>. The
201default value is 45, which is enough for 14 capturing subexpressions for
202<b>pcre[16|32]_exec()</b> or 22 different matches for
203<b>pcre[16|32]_dfa_exec()</b>.
204The vector size can be changed for individual matching calls by including \O
205in the data line (see below).
206</P>
207<P>
208<b>-p</b>
209Behave as if each pattern has the <b>/P</b> modifier; the POSIX wrapper API is
210used to call PCRE. None of the other options has any effect when <b>-p</b> is
211set. This option can be used only with the 8-bit library.
212</P>
213<P>
214<b>-q</b>
215Do not output the version number of <b>pcretest</b> at the start of execution.
216</P>
217<P>
218<b>-S</b> <i>size</i>
219On Unix-like systems, set the size of the run-time stack to <i>size</i>
220megabytes.
221</P>
222<P>
223<b>-s</b> or <b>-s+</b>
224Behave as if each pattern has the <b>/S</b> modifier; in other words, force each
225pattern to be studied. If <b>-s+</b> is used, all the JIT compile options are
226passed to <b>pcre[16|32]_study()</b>, causing just-in-time optimization to be set
227up if it is available, for both full and partial matching. Specific JIT compile
228options can be selected by following <b>-s+</b> with a digit in the range 1 to
2297, which selects the JIT compile modes as follows:
230<pre>
231  1  normal match only
232  2  soft partial match only
233  3  normal match and soft partial match
234  4  hard partial match only
235  6  soft and hard partial match
236  7  all three modes (default)
237</pre>
238If <b>-s++</b> is used instead of <b>-s+</b> (with or without a following digit),
239the text "(JIT)" is added to the first output line after a match or no match
240when JIT-compiled code was actually used.
241<br>
242<br>
243Note that there are pattern options that can override <b>-s</b>, either
244specifying no studying at all, or suppressing JIT compilation.
245<br>
246<br>
247If the <b>/I</b> or <b>/D</b> option is present on a pattern (requesting output
248about the compiled pattern), information about the result of studying is not
249included when studying is caused only by <b>-s</b> and neither <b>-i</b> nor
250<b>-d</b> is present on the command line. This behaviour means that the output
251from tests that are run with and without <b>-s</b> should be identical, except
252when options that output information about the actual running of a match are
253set.
254<br>
255<br>
256The <b>-M</b>, <b>-t</b>, and <b>-tm</b> options, which give information about
257resources used, are likely to produce different output with and without
258<b>-s</b>. Output may also differ if the <b>/C</b> option is present on an
259individual pattern. This uses callouts to trace the the matching process, and
260this may be different between studied and non-studied patterns. If the pattern
261contains (*MARK) items there may also be differences, for the same reason. The
262<b>-s</b> command line option can be overridden for specific patterns that
263should never be studied (see the <b>/S</b> pattern modifier below).
264</P>
265<P>
266<b>-t</b>
267Run each compile, study, and match many times with a timer, and output the
268resulting times per compile, study, or match (in milliseconds). Do not set
269<b>-m</b> with <b>-t</b>, because you will then get the size output a zillion
270times, and the timing will be distorted. You can control the number of
271iterations that are used for timing by following <b>-t</b> with a number (as a
272separate item on the command line). For example, "-t 1000" iterates 1000 times.
273The default is to iterate 500000 times.
274</P>
275<P>
276<b>-tm</b>
277This is like <b>-t</b> except that it times only the matching phase, not the
278compile or study phases.
279</P>
280<P>
281<b>-T</b> <b>-TM</b>
282These behave like <b>-t</b> and <b>-tm</b>, but in addition, at the end of a run,
283the total times for all compiles, studies, and matches are output.
284</P>
285<br><a name="SEC5" href="#TOC1">DESCRIPTION</a><br>
286<P>
287If <b>pcretest</b> is given two filename arguments, it reads from the first and
288writes to the second. If it is given only one filename argument, it reads from
289that file and writes to stdout. Otherwise, it reads from stdin and writes to
290stdout, and prompts for each line of input, using "re&#62;" to prompt for regular
291expressions, and "data&#62;" to prompt for data lines.
292</P>
293<P>
294When <b>pcretest</b> is built, a configuration option can specify that it should
295be linked with the <b>libreadline</b> library. When this is done, if the input
296is from a terminal, it is read using the <b>readline()</b> function. This
297provides line-editing and history facilities. The output from the <b>-help</b>
298option states whether or not <b>readline()</b> will be used.
299</P>
300<P>
301The program handles any number of sets of input on a single input file. Each
302set starts with a regular expression, and continues with any number of data
303lines to be matched against that pattern.
304</P>
305<P>
306Each data line is matched separately and independently. If you want to do
307multi-line matches, you have to use the \n escape sequence (or \r or \r\n,
308etc., depending on the newline setting) in a single line of input to encode the
309newline sequences. There is no limit on the length of data lines; the input
310buffer is automatically extended if it is too small.
311</P>
312<P>
313An empty line signals the end of the data lines, at which point a new regular
314expression is read. The regular expressions are given enclosed in any
315non-alphanumeric delimiters other than backslash, for example:
316<pre>
317  /(a|bc)x+yz/
318</pre>
319White space before the initial delimiter is ignored. A regular expression may
320be continued over several input lines, in which case the newline characters are
321included within it. It is possible to include the delimiter within the pattern
322by escaping it, for example
323<pre>
324  /abc\/def/
325</pre>
326If you do so, the escape and the delimiter form part of the pattern, but since
327delimiters are always non-alphanumeric, this does not affect its interpretation.
328If the terminating delimiter is immediately followed by a backslash, for
329example,
330<pre>
331  /abc/\
332</pre>
333then a backslash is added to the end of the pattern. This is done to provide a
334way of testing the error condition that arises if a pattern finishes with a
335backslash, because
336<pre>
337  /abc\/
338</pre>
339is interpreted as the first line of a pattern that starts with "abc/", causing
340pcretest to read the next line as a continuation of the regular expression.
341</P>
342<br><a name="SEC6" href="#TOC1">PATTERN MODIFIERS</a><br>
343<P>
344A pattern may be followed by any number of modifiers, which are mostly single
345characters, though some of these can be qualified by further characters.
346Following Perl usage, these are referred to below as, for example, "the
347<b>/i</b> modifier", even though the delimiter of the pattern need not always be
348a slash, and no slash is used when writing modifiers. White space may appear
349between the final pattern delimiter and the first modifier, and between the
350modifiers themselves. For reference, here is a complete list of modifiers. They
351fall into several groups that are described in detail in the following
352sections.
353<pre>
354  <b>/8</b>              set UTF mode
355  <b>/9</b>              set PCRE_NEVER_UTF (locks out UTF mode)
356  <b>/?</b>              disable UTF validity check
357  <b>/+</b>              show remainder of subject after match
358  <b>/=</b>              show all captures (not just those that are set)
359
360  <b>/A</b>              set PCRE_ANCHORED
361  <b>/B</b>              show compiled code
362  <b>/C</b>              set PCRE_AUTO_CALLOUT
363  <b>/D</b>              same as <b>/B</b> plus <b>/I</b>
364  <b>/E</b>              set PCRE_DOLLAR_ENDONLY
365  <b>/F</b>              flip byte order in compiled pattern
366  <b>/f</b>              set PCRE_FIRSTLINE
367  <b>/G</b>              find all matches (shorten string)
368  <b>/g</b>              find all matches (use startoffset)
369  <b>/I</b>              show information about pattern
370  <b>/i</b>              set PCRE_CASELESS
371  <b>/J</b>              set PCRE_DUPNAMES
372  <b>/K</b>              show backtracking control names
373  <b>/L</b>              set locale
374  <b>/M</b>              show compiled memory size
375  <b>/m</b>              set PCRE_MULTILINE
376  <b>/N</b>              set PCRE_NO_AUTO_CAPTURE
377  <b>/O</b>              set PCRE_NO_AUTO_POSSESS
378  <b>/P</b>              use the POSIX wrapper
379  <b>/Q</b>              test external stack check function
380  <b>/S</b>              study the pattern after compilation
381  <b>/s</b>              set PCRE_DOTALL
382  <b>/T</b>              select character tables
383  <b>/U</b>              set PCRE_UNGREEDY
384  <b>/W</b>              set PCRE_UCP
385  <b>/X</b>              set PCRE_EXTRA
386  <b>/x</b>              set PCRE_EXTENDED
387  <b>/Y</b>              set PCRE_NO_START_OPTIMIZE
388  <b>/Z</b>              don't show lengths in <b>/B</b> output
389
390  <b>/&#60;any&#62;</b>          set PCRE_NEWLINE_ANY
391  <b>/&#60;anycrlf&#62;</b>      set PCRE_NEWLINE_ANYCRLF
392  <b>/&#60;cr&#62;</b>           set PCRE_NEWLINE_CR
393  <b>/&#60;crlf&#62;</b>         set PCRE_NEWLINE_CRLF
394  <b>/&#60;lf&#62;</b>           set PCRE_NEWLINE_LF
395  <b>/&#60;bsr_anycrlf&#62;</b>  set PCRE_BSR_ANYCRLF
396  <b>/&#60;bsr_unicode&#62;</b>  set PCRE_BSR_UNICODE
397  <b>/&#60;JS&#62;</b>           set PCRE_JAVASCRIPT_COMPAT
398
399</PRE>
400</P>
401<br><b>
402Perl-compatible modifiers
403</b><br>
404<P>
405The <b>/i</b>, <b>/m</b>, <b>/s</b>, and <b>/x</b> modifiers set the PCRE_CASELESS,
406PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when
407<b>pcre[16|32]_compile()</b> is called. These four modifier letters have the same
408effect as they do in Perl. For example:
409<pre>
410  /caseless/i
411
412</PRE>
413</P>
414<br><b>
415Modifiers for other PCRE options
416</b><br>
417<P>
418The following table shows additional modifiers for setting PCRE compile-time
419options that do not correspond to anything in Perl:
420<pre>
421  <b>/8</b>              PCRE_UTF8           ) when using the 8-bit
422  <b>/?</b>              PCRE_NO_UTF8_CHECK  )   library
423
424  <b>/8</b>              PCRE_UTF16          ) when using the 16-bit
425  <b>/?</b>              PCRE_NO_UTF16_CHECK )   library
426
427  <b>/8</b>              PCRE_UTF32          ) when using the 32-bit
428  <b>/?</b>              PCRE_NO_UTF32_CHECK )   library
429
430  <b>/9</b>              PCRE_NEVER_UTF
431  <b>/A</b>              PCRE_ANCHORED
432  <b>/C</b>              PCRE_AUTO_CALLOUT
433  <b>/E</b>              PCRE_DOLLAR_ENDONLY
434  <b>/f</b>              PCRE_FIRSTLINE
435  <b>/J</b>              PCRE_DUPNAMES
436  <b>/N</b>              PCRE_NO_AUTO_CAPTURE
437  <b>/O</b>              PCRE_NO_AUTO_POSSESS
438  <b>/U</b>              PCRE_UNGREEDY
439  <b>/W</b>              PCRE_UCP
440  <b>/X</b>              PCRE_EXTRA
441  <b>/Y</b>              PCRE_NO_START_OPTIMIZE
442  <b>/&#60;any&#62;</b>          PCRE_NEWLINE_ANY
443  <b>/&#60;anycrlf&#62;</b>      PCRE_NEWLINE_ANYCRLF
444  <b>/&#60;cr&#62;</b>           PCRE_NEWLINE_CR
445  <b>/&#60;crlf&#62;</b>         PCRE_NEWLINE_CRLF
446  <b>/&#60;lf&#62;</b>           PCRE_NEWLINE_LF
447  <b>/&#60;bsr_anycrlf&#62;</b>  PCRE_BSR_ANYCRLF
448  <b>/&#60;bsr_unicode&#62;</b>  PCRE_BSR_UNICODE
449  <b>/&#60;JS&#62;</b>           PCRE_JAVASCRIPT_COMPAT
450</pre>
451The modifiers that are enclosed in angle brackets are literal strings as shown,
452including the angle brackets, but the letters within can be in either case.
453This example sets multiline matching with CRLF as the line ending sequence:
454<pre>
455  /^abc/m&#60;CRLF&#62;
456</pre>
457As well as turning on the PCRE_UTF8/16/32 option, the <b>/8</b> modifier causes
458all non-printing characters in output strings to be printed using the
459\x{hh...} notation. Otherwise, those less than 0x100 are output in hex without
460the curly brackets.
461</P>
462<P>
463Full details of the PCRE options are given in the
464<a href="pcreapi.html"><b>pcreapi</b></a>
465documentation.
466</P>
467<br><b>
468Finding all matches in a string
469</b><br>
470<P>
471Searching for all possible matches within each subject string can be requested
472by the <b>/g</b> or <b>/G</b> modifier. After finding a match, PCRE is called
473again to search the remainder of the subject string. The difference between
474<b>/g</b> and <b>/G</b> is that the former uses the <i>startoffset</i> argument to
475<b>pcre[16|32]_exec()</b> to start searching at a new point within the entire
476string (which is in effect what Perl does), whereas the latter passes over a
477shortened substring. This makes a difference to the matching process if the
478pattern begins with a lookbehind assertion (including \b or \B).
479</P>
480<P>
481If any call to <b>pcre[16|32]_exec()</b> in a <b>/g</b> or <b>/G</b> sequence matches
482an empty string, the next call is done with the PCRE_NOTEMPTY_ATSTART and
483PCRE_ANCHORED flags set in order to search for another, non-empty, match at the
484same point. If this second match fails, the start offset is advanced, and the
485normal match is retried. This imitates the way Perl handles such cases when
486using the <b>/g</b> modifier or the <b>split()</b> function. Normally, the start
487offset is advanced by one character, but if the newline convention recognizes
488CRLF as a newline, and the current character is CR followed by LF, an advance
489of two is used.
490</P>
491<br><b>
492Other modifiers
493</b><br>
494<P>
495There are yet more modifiers for controlling the way <b>pcretest</b>
496operates.
497</P>
498<P>
499The <b>/+</b> modifier requests that as well as outputting the substring that
500matched the entire pattern, <b>pcretest</b> should in addition output the
501remainder of the subject string. This is useful for tests where the subject
502contains multiple copies of the same substring. If the <b>+</b> modifier appears
503twice, the same action is taken for captured substrings. In each case the
504remainder is output on the following line with a plus character following the
505capture number. Note that this modifier must not immediately follow the /S
506modifier because /S+ and /S++ have other meanings.
507</P>
508<P>
509The <b>/=</b> modifier requests that the values of all potential captured
510parentheses be output after a match. By default, only those up to the highest
511one actually used in the match are output (corresponding to the return code
512from <b>pcre[16|32]_exec()</b>). Values in the offsets vector corresponding to
513higher numbers should be set to -1, and these are output as "&#60;unset&#62;". This
514modifier gives a way of checking that this is happening.
515</P>
516<P>
517The <b>/B</b> modifier is a debugging feature. It requests that <b>pcretest</b>
518output a representation of the compiled code after compilation. Normally this
519information contains length and offset values; however, if <b>/Z</b> is also
520present, this data is replaced by spaces. This is a special feature for use in
521the automatic test scripts; it ensures that the same output is generated for
522different internal link sizes.
523</P>
524<P>
525The <b>/D</b> modifier is a PCRE debugging feature, and is equivalent to
526<b>/BI</b>, that is, both the <b>/B</b> and the <b>/I</b> modifiers.
527</P>
528<P>
529The <b>/F</b> modifier causes <b>pcretest</b> to flip the byte order of the
5302-byte and 4-byte fields in the compiled pattern. This facility is for testing
531the feature in PCRE that allows it to execute patterns that were compiled on a
532host with a different endianness. This feature is not available when the POSIX
533interface to PCRE is being used, that is, when the <b>/P</b> pattern modifier is
534specified. See also the section about saving and reloading compiled patterns
535below.
536</P>
537<P>
538The <b>/I</b> modifier requests that <b>pcretest</b> output information about the
539compiled pattern (whether it is anchored, has a fixed first character, and
540so on). It does this by calling <b>pcre[16|32]_fullinfo()</b> after compiling a
541pattern. If the pattern is studied, the results of that are also output. In
542this output, the word "char" means a non-UTF character, that is, the value of a
543single data item (8-bit, 16-bit, or 32-bit, depending on the library that is
544being tested).
545</P>
546<P>
547The <b>/K</b> modifier requests <b>pcretest</b> to show names from backtracking
548control verbs that are returned from calls to <b>pcre[16|32]_exec()</b>. It causes
549<b>pcretest</b> to create a <b>pcre[16|32]_extra</b> block if one has not already
550been created by a call to <b>pcre[16|32]_study()</b>, and to set the
551PCRE_EXTRA_MARK flag and the <b>mark</b> field within it, every time that
552<b>pcre[16|32]_exec()</b> is called. If the variable that the <b>mark</b> field
553points to is non-NULL for a match, non-match, or partial match, <b>pcretest</b>
554prints the string to which it points. For a match, this is shown on a line by
555itself, tagged with "MK:". For a non-match it is added to the message.
556</P>
557<P>
558The <b>/L</b> modifier must be followed directly by the name of a locale, for
559example,
560<pre>
561  /pattern/Lfr_FR
562</pre>
563For this reason, it must be the last modifier. The given locale is set,
564<b>pcre[16|32]_maketables()</b> is called to build a set of character tables for
565the locale, and this is then passed to <b>pcre[16|32]_compile()</b> when compiling
566the regular expression. Without an <b>/L</b> (or <b>/T</b>) modifier, NULL is
567passed as the tables pointer; that is, <b>/L</b> applies only to the expression
568on which it appears.
569</P>
570<P>
571The <b>/M</b> modifier causes the size in bytes of the memory block used to hold
572the compiled pattern to be output. This does not include the size of the
573<b>pcre[16|32]</b> block; it is just the actual compiled data. If the pattern is
574successfully studied with the PCRE_STUDY_JIT_COMPILE option, the size of the
575JIT compiled code is also output.
576</P>
577<P>
578The <b>/Q</b> modifier is used to test the use of <b>pcre_stack_guard</b>. It
579must be followed by '0' or '1', specifying the return code to be given from an
580external function that is passed to PCRE and used for stack checking during
581compilation (see the
582<a href="pcreapi.html"><b>pcreapi</b></a>
583documentation for details).
584</P>
585<P>
586The <b>/S</b> modifier causes <b>pcre[16|32]_study()</b> to be called after the
587expression has been compiled, and the results used when the expression is
588matched. There are a number of qualifying characters that may follow <b>/S</b>.
589They may appear in any order.
590</P>
591<P>
592If <b>/S</b> is followed by an exclamation mark, <b>pcre[16|32]_study()</b> is
593called with the PCRE_STUDY_EXTRA_NEEDED option, causing it always to return a
594<b>pcre_extra</b> block, even when studying discovers no useful information.
595</P>
596<P>
597If <b>/S</b> is followed by a second S character, it suppresses studying, even
598if it was requested externally by the <b>-s</b> command line option. This makes
599it possible to specify that certain patterns are always studied, and others are
600never studied, independently of <b>-s</b>. This feature is used in the test
601files in a few cases where the output is different when the pattern is studied.
602</P>
603<P>
604If the <b>/S</b> modifier is followed by a + character, the call to
605<b>pcre[16|32]_study()</b> is made with all the JIT study options, requesting
606just-in-time optimization support if it is available, for both normal and
607partial matching. If you want to restrict the JIT compiling modes, you can
608follow <b>/S+</b> with a digit in the range 1 to 7:
609<pre>
610  1  normal match only
611  2  soft partial match only
612  3  normal match and soft partial match
613  4  hard partial match only
614  6  soft and hard partial match
615  7  all three modes (default)
616</pre>
617If <b>/S++</b> is used instead of <b>/S+</b> (with or without a following digit),
618the text "(JIT)" is added to the first output line after a match or no match
619when JIT-compiled code was actually used.
620</P>
621<P>
622Note that there is also an independent <b>/+</b> modifier; it must not be given
623immediately after <b>/S</b> or <b>/S+</b> because this will be misinterpreted.
624</P>
625<P>
626If JIT studying is successful, the compiled JIT code will automatically be used
627when <b>pcre[16|32]_exec()</b> is run, except when incompatible run-time options
628are specified. For more details, see the
629<a href="pcrejit.html"><b>pcrejit</b></a>
630documentation. See also the <b>\J</b> escape sequence below for a way of
631setting the size of the JIT stack.
632</P>
633<P>
634Finally, if <b>/S</b> is followed by a minus character, JIT compilation is
635suppressed, even if it was requested externally by the <b>-s</b> command line
636option. This makes it possible to specify that JIT is never to be used for
637certain patterns.
638</P>
639<P>
640The <b>/T</b> modifier must be followed by a single digit. It causes a specific
641set of built-in character tables to be passed to <b>pcre[16|32]_compile()</b>. It
642is used in the standard PCRE tests to check behaviour with different character
643tables. The digit specifies the tables as follows:
644<pre>
645  0   the default ASCII tables, as distributed in
646        pcre_chartables.c.dist
647  1   a set of tables defining ISO 8859 characters
648</pre>
649In table 1, some characters whose codes are greater than 128 are identified as
650letters, digits, spaces, etc.
651</P>
652<br><b>
653Using the POSIX wrapper API
654</b><br>
655<P>
656The <b>/P</b> modifier causes <b>pcretest</b> to call PCRE via the POSIX wrapper
657API rather than its native API. This supports only the 8-bit library. When
658<b>/P</b> is set, the following modifiers set options for the <b>regcomp()</b>
659function:
660<pre>
661  /i    REG_ICASE
662  /m    REG_NEWLINE
663  /N    REG_NOSUB
664  /s    REG_DOTALL     )
665  /U    REG_UNGREEDY   ) These options are not part of
666  /W    REG_UCP        )   the POSIX standard
667  /8    REG_UTF8       )
668</pre>
669The <b>/+</b> modifier works as described above. All other modifiers are
670ignored.
671</P>
672<br><b>
673Locking out certain modifiers
674</b><br>
675<P>
676PCRE can be compiled with or without support for certain features such as
677UTF-8/16/32 or Unicode properties. Accordingly, the standard tests are split up
678into a number of different files that are selected for running depending on
679which features are available. When updating the tests, it is all too easy to
680put a new test into the wrong file by mistake; for example, to put a test that
681requires UTF support into a file that is used when it is not available. To help
682detect such mistakes as early as possible, there is a facility for locking out
683specific modifiers. If an input line for <b>pcretest</b> starts with the string
684"&#60; forbid " the following sequence of characters is taken as a list of
685forbidden modifiers. For example, in the test files that must not use UTF or
686Unicode property support, this line appears:
687<pre>
688  &#60; forbid 8W
689</pre>
690This locks out the /8 and /W modifiers. An immediate error is given if they are
691subsequently encountered. If the character string contains &#60; but not &#62;, all the
692multi-character modifiers that begin with &#60; are locked out. Otherwise, such
693modifiers must be explicitly listed, for example:
694<pre>
695  &#60; forbid &#60;JS&#62;&#60;cr&#62;
696</pre>
697There must be a single space between &#60; and "forbid" for this feature to be
698recognised. If there is not, the line is interpreted either as a request to
699re-load a pre-compiled pattern (see "SAVING AND RELOADING COMPILED PATTERNS"
700below) or, if there is a another &#60; character, as a pattern that uses &#60; as its
701delimiter.
702</P>
703<br><a name="SEC7" href="#TOC1">DATA LINES</a><br>
704<P>
705Before each data line is passed to <b>pcre[16|32]_exec()</b>, leading and trailing
706white space is removed, and it is then scanned for \ escapes. Some of these
707are pretty esoteric features, intended for checking out some of the more
708complicated features of PCRE. If you are just testing "ordinary" regular
709expressions, you probably don't need any of these. The following escapes are
710recognized:
711<pre>
712  \a         alarm (BEL, \x07)
713  \b         backspace (\x08)
714  \e         escape (\x27)
715  \f         form feed (\x0c)
716  \n         newline (\x0a)
717  \qdd       set the PCRE_MATCH_LIMIT limit to dd (any number of digits)
718  \r         carriage return (\x0d)
719  \t         tab (\x09)
720  \v         vertical tab (\x0b)
721  \nnn       octal character (up to 3 octal digits); always
722               a byte unless &#62; 255 in UTF-8 or 16-bit or 32-bit mode
723  \o{dd...}  octal character (any number of octal digits}
724  \xhh       hexadecimal byte (up to 2 hex digits)
725  \x{hh...}  hexadecimal character (any number of hex digits)
726  \A         pass the PCRE_ANCHORED option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
727  \B         pass the PCRE_NOTBOL option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
728  \Cdd       call pcre[16|32]_copy_substring() for substring dd after a successful match (number less than 32)
729  \Cname     call pcre[16|32]_copy_named_substring() for substring "name" after a successful match (name termin-
730               ated by next non alphanumeric character)
731  \C+        show the current captured substrings at callout time
732  \C-        do not supply a callout function
733  \C!n       return 1 instead of 0 when callout number n is reached
734  \C!n!m     return 1 instead of 0 when callout number n is reached for the nth time
735  \C*n       pass the number n (may be negative) as callout data; this is used as the callout return value
736  \D         use the <b>pcre[16|32]_dfa_exec()</b> match function
737  \F         only shortest match for <b>pcre[16|32]_dfa_exec()</b>
738  \Gdd       call pcre[16|32]_get_substring() for substring dd after a successful match (number less than 32)
739  \Gname     call pcre[16|32]_get_named_substring() for substring "name" after a successful match (name termin-
740               ated by next non-alphanumeric character)
741  \Jdd       set up a JIT stack of dd kilobytes maximum (any number of digits)
742  \L         call pcre[16|32]_get_substringlist() after a successful match
743  \M         discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings
744  \N         pass the PCRE_NOTEMPTY option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>; if used twice, pass the
745               PCRE_NOTEMPTY_ATSTART option
746  \Odd       set the size of the output vector passed to <b>pcre[16|32]_exec()</b> to dd (any number of digits)
747  \P         pass the PCRE_PARTIAL_SOFT option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>; if used twice, pass the
748               PCRE_PARTIAL_HARD option
749  \Qdd       set the PCRE_MATCH_LIMIT_RECURSION limit to dd (any number of digits)
750  \R         pass the PCRE_DFA_RESTART option to <b>pcre[16|32]_dfa_exec()</b>
751  \S         output details of memory get/free calls during matching
752  \Y         pass the PCRE_NO_START_OPTIMIZE option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
753  \Z         pass the PCRE_NOTEOL option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
754  \?         pass the PCRE_NO_UTF[8|16|32]_CHECK option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
755  \&#62;dd       start the match at offset dd (optional "-"; then any number of digits); this sets the <i>startoffset</i>
756               argument for <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
757  \&#60;cr&#62;      pass the PCRE_NEWLINE_CR option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
758  \&#60;lf&#62;      pass the PCRE_NEWLINE_LF option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
759  \&#60;crlf&#62;    pass the PCRE_NEWLINE_CRLF option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
760  \&#60;anycrlf&#62; pass the PCRE_NEWLINE_ANYCRLF option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
761  \&#60;any&#62;     pass the PCRE_NEWLINE_ANY option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
762</pre>
763The use of \x{hh...} is not dependent on the use of the <b>/8</b> modifier on
764the pattern. It is recognized always. There may be any number of hexadecimal
765digits inside the braces; invalid values provoke error messages.
766</P>
767<P>
768Note that \xhh specifies one byte rather than one character in UTF-8 mode;
769this makes it possible to construct invalid UTF-8 sequences for testing
770purposes. On the other hand, \x{hh} is interpreted as a UTF-8 character in
771UTF-8 mode, generating more than one byte if the value is greater than 127.
772When testing the 8-bit library not in UTF-8 mode, \x{hh} generates one byte
773for values less than 256, and causes an error for greater values.
774</P>
775<P>
776In UTF-16 mode, all 4-digit \x{hhhh} values are accepted. This makes it
777possible to construct invalid UTF-16 sequences for testing purposes.
778</P>
779<P>
780In UTF-32 mode, all 4- to 8-digit \x{...} values are accepted. This makes it
781possible to construct invalid UTF-32 sequences for testing purposes.
782</P>
783<P>
784The escapes that specify line ending sequences are literal strings, exactly as
785shown. No more than one newline setting should be present in any data line.
786</P>
787<P>
788A backslash followed by anything else just escapes the anything else. If
789the very last character is a backslash, it is ignored. This gives a way of
790passing an empty line as data, since a real empty line terminates the data
791input.
792</P>
793<P>
794The <b>\J</b> escape provides a way of setting the maximum stack size that is
795used by the just-in-time optimization code. It is ignored if JIT optimization
796is not being used. Providing a stack that is larger than the default 32K is
797necessary only for very complicated patterns.
798</P>
799<P>
800If \M is present, <b>pcretest</b> calls <b>pcre[16|32]_exec()</b> several times,
801with different values in the <i>match_limit</i> and <i>match_limit_recursion</i>
802fields of the <b>pcre[16|32]_extra</b> data structure, until it finds the minimum
803numbers for each parameter that allow <b>pcre[16|32]_exec()</b> to complete without
804error. Because this is testing a specific feature of the normal interpretive
805<b>pcre[16|32]_exec()</b> execution, the use of any JIT optimization that might
806have been set up by the <b>/S+</b> qualifier of <b>-s+</b> option is disabled.
807</P>
808<P>
809The <i>match_limit</i> number is a measure of the amount of backtracking
810that takes place, and checking it out can be instructive. For most simple
811matches, the number is quite small, but for patterns with very large numbers of
812matching possibilities, it can become large very quickly with increasing length
813of subject string. The <i>match_limit_recursion</i> number is a measure of how
814much stack (or, if PCRE is compiled with NO_RECURSE, how much heap) memory is
815needed to complete the match attempt.
816</P>
817<P>
818When \O is used, the value specified may be higher or lower than the size set
819by the <b>-O</b> command line option (or defaulted to 45); \O applies only to
820the call of <b>pcre[16|32]_exec()</b> for the line in which it appears.
821</P>
822<P>
823If the <b>/P</b> modifier was present on the pattern, causing the POSIX wrapper
824API to be used, the only option-setting sequences that have any effect are \B,
825\N, and \Z, causing REG_NOTBOL, REG_NOTEMPTY, and REG_NOTEOL, respectively,
826to be passed to <b>regexec()</b>.
827</P>
828<br><a name="SEC8" href="#TOC1">THE ALTERNATIVE MATCHING FUNCTION</a><br>
829<P>
830By default, <b>pcretest</b> uses the standard PCRE matching function,
831<b>pcre[16|32]_exec()</b> to match each data line. PCRE also supports an
832alternative matching function, <b>pcre[16|32]_dfa_test()</b>, which operates in a
833different way, and has some restrictions. The differences between the two
834functions are described in the
835<a href="pcrematching.html"><b>pcrematching</b></a>
836documentation.
837</P>
838<P>
839If a data line contains the \D escape sequence, or if the command line
840contains the <b>-dfa</b> option, the alternative matching function is used.
841This function finds all possible matches at a given point. If, however, the \F
842escape sequence is present in the data line, it stops after the first match is
843found. This is always the shortest possible match.
844</P>
845<br><a name="SEC9" href="#TOC1">DEFAULT OUTPUT FROM PCRETEST</a><br>
846<P>
847This section describes the output when the normal matching function,
848<b>pcre[16|32]_exec()</b>, is being used.
849</P>
850<P>
851When a match succeeds, <b>pcretest</b> outputs the list of captured substrings
852that <b>pcre[16|32]_exec()</b> returns, starting with number 0 for the string that
853matched the whole pattern. Otherwise, it outputs "No match" when the return is
854PCRE_ERROR_NOMATCH, and "Partial match:" followed by the partially matching
855substring when <b>pcre[16|32]_exec()</b> returns PCRE_ERROR_PARTIAL. (Note that
856this is the entire substring that was inspected during the partial match; it
857may include characters before the actual match start if a lookbehind assertion,
858\K, \b, or \B was involved.) For any other return, <b>pcretest</b> outputs
859the PCRE negative error number and a short descriptive phrase. If the error is
860a failed UTF string check, the offset of the start of the failing character and
861the reason code are also output, provided that the size of the output vector is
862at least two. Here is an example of an interactive <b>pcretest</b> run.
863<pre>
864  $ pcretest
865  PCRE version 8.13 2011-04-30
866
867    re&#62; /^abc(\d+)/
868  data&#62; abc123
869   0: abc123
870   1: 123
871  data&#62; xyz
872  No match
873</pre>
874Unset capturing substrings that are not followed by one that is set are not
875returned by <b>pcre[16|32]_exec()</b>, and are not shown by <b>pcretest</b>. In the
876following example, there are two capturing substrings, but when the first data
877line is matched, the second, unset substring is not shown. An "internal" unset
878substring is shown as "&#60;unset&#62;", as for the second data line.
879<pre>
880    re&#62; /(a)|(b)/
881  data&#62; a
882   0: a
883   1: a
884  data&#62; b
885   0: b
886   1: &#60;unset&#62;
887   2: b
888</pre>
889If the strings contain any non-printing characters, they are output as \xhh
890escapes if the value is less than 256 and UTF mode is not set. Otherwise they
891are output as \x{hh...} escapes. See below for the definition of non-printing
892characters. If the pattern has the <b>/+</b> modifier, the output for substring
8930 is followed by the the rest of the subject string, identified by "0+" like
894this:
895<pre>
896    re&#62; /cat/+
897  data&#62; cataract
898   0: cat
899   0+ aract
900</pre>
901If the pattern has the <b>/g</b> or <b>/G</b> modifier, the results of successive
902matching attempts are output in sequence, like this:
903<pre>
904    re&#62; /\Bi(\w\w)/g
905  data&#62; Mississippi
906   0: iss
907   1: ss
908   0: iss
909   1: ss
910   0: ipp
911   1: pp
912</pre>
913"No match" is output only if the first match attempt fails. Here is an example
914of a failure message (the offset 4 that is specified by \&#62;4 is past the end of
915the subject string):
916<pre>
917    re&#62; /xyz/
918  data&#62; xyz\&#62;4
919  Error -24 (bad offset value)
920</PRE>
921</P>
922<P>
923If any of the sequences <b>\C</b>, <b>\G</b>, or <b>\L</b> are present in a
924data line that is successfully matched, the substrings extracted by the
925convenience functions are output with C, G, or L after the string number
926instead of a colon. This is in addition to the normal full list. The string
927length (that is, the return from the extraction function) is given in
928parentheses after each string for <b>\C</b> and <b>\G</b>.
929</P>
930<P>
931Note that whereas patterns can be continued over several lines (a plain "&#62;"
932prompt is used for continuations), data lines may not. However newlines can be
933included in data by means of the \n escape (or \r, \r\n, etc., depending on
934the newline sequence setting).
935</P>
936<br><a name="SEC10" href="#TOC1">OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION</a><br>
937<P>
938When the alternative matching function, <b>pcre[16|32]_dfa_exec()</b>, is used (by
939means of the \D escape sequence or the <b>-dfa</b> command line option), the
940output consists of a list of all the matches that start at the first point in
941the subject where there is at least one match. For example:
942<pre>
943    re&#62; /(tang|tangerine|tan)/
944  data&#62; yellow tangerine\D
945   0: tangerine
946   1: tang
947   2: tan
948</pre>
949(Using the normal matching function on this data finds only "tang".) The
950longest matching string is always given first (and numbered zero). After a
951PCRE_ERROR_PARTIAL return, the output is "Partial match:", followed by the
952partially matching substring. (Note that this is the entire substring that was
953inspected during the partial match; it may include characters before the actual
954match start if a lookbehind assertion, \K, \b, or \B was involved.)
955</P>
956<P>
957If <b>/g</b> is present on the pattern, the search for further matches resumes
958at the end of the longest match. For example:
959<pre>
960    re&#62; /(tang|tangerine|tan)/g
961  data&#62; yellow tangerine and tangy sultana\D
962   0: tangerine
963   1: tang
964   2: tan
965   0: tang
966   1: tan
967   0: tan
968</pre>
969Since the matching function does not support substring capture, the escape
970sequences that are concerned with captured substrings are not relevant.
971</P>
972<br><a name="SEC11" href="#TOC1">RESTARTING AFTER A PARTIAL MATCH</a><br>
973<P>
974When the alternative matching function has given the PCRE_ERROR_PARTIAL return,
975indicating that the subject partially matched the pattern, you can restart the
976match with additional subject data by means of the \R escape sequence. For
977example:
978<pre>
979    re&#62; /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
980  data&#62; 23ja\P\D
981  Partial match: 23ja
982  data&#62; n05\R\D
983   0: n05
984</pre>
985For further information about partial matching, see the
986<a href="pcrepartial.html"><b>pcrepartial</b></a>
987documentation.
988</P>
989<br><a name="SEC12" href="#TOC1">CALLOUTS</a><br>
990<P>
991If the pattern contains any callout requests, <b>pcretest</b>'s callout function
992is called during matching. This works with both matching functions. By default,
993the called function displays the callout number, the start and current
994positions in the text at the callout time, and the next pattern item to be
995tested. For example:
996<pre>
997  ---&#62;pqrabcdef
998    0    ^  ^     \d
999</pre>
1000This output indicates that callout number 0 occurred for a match attempt
1001starting at the fourth character of the subject string, when the pointer was at
1002the seventh character of the data, and when the next pattern item was \d. Just
1003one circumflex is output if the start and current positions are the same.
1004</P>
1005<P>
1006Callouts numbered 255 are assumed to be automatic callouts, inserted as a
1007result of the <b>/C</b> pattern modifier. In this case, instead of showing the
1008callout number, the offset in the pattern, preceded by a plus, is output. For
1009example:
1010<pre>
1011    re&#62; /\d?[A-E]\*/C
1012  data&#62; E*
1013  ---&#62;E*
1014   +0 ^      \d?
1015   +3 ^      [A-E]
1016   +8 ^^     \*
1017  +10 ^ ^
1018   0: E*
1019</pre>
1020If a pattern contains (*MARK) items, an additional line is output whenever
1021a change of latest mark is passed to the callout function. For example:
1022<pre>
1023    re&#62; /a(*MARK:X)bc/C
1024  data&#62; abc
1025  ---&#62;abc
1026   +0 ^       a
1027   +1 ^^      (*MARK:X)
1028  +10 ^^      b
1029  Latest Mark: X
1030  +11 ^ ^     c
1031  +12 ^  ^
1032   0: abc
1033</pre>
1034The mark changes between matching "a" and "b", but stays the same for the rest
1035of the match, so nothing more is output. If, as a result of backtracking, the
1036mark reverts to being unset, the text "&#60;unset&#62;" is output.
1037</P>
1038<P>
1039The callout function in <b>pcretest</b> returns zero (carry on matching) by
1040default, but you can use a \C item in a data line (as described above) to
1041change this and other parameters of the callout.
1042</P>
1043<P>
1044Inserting callouts can be helpful when using <b>pcretest</b> to check
1045complicated regular expressions. For further information about callouts, see
1046the
1047<a href="pcrecallout.html"><b>pcrecallout</b></a>
1048documentation.
1049</P>
1050<br><a name="SEC13" href="#TOC1">NON-PRINTING CHARACTERS</a><br>
1051<P>
1052When <b>pcretest</b> is outputting text in the compiled version of a pattern,
1053bytes other than 32-126 are always treated as non-printing characters are are
1054therefore shown as hex escapes.
1055</P>
1056<P>
1057When <b>pcretest</b> is outputting text that is a matched part of a subject
1058string, it behaves in the same way, unless a different locale has been set for
1059the pattern (using the <b>/L</b> modifier). In this case, the <b>isprint()</b>
1060function to distinguish printing and non-printing characters.
1061</P>
1062<br><a name="SEC14" href="#TOC1">SAVING AND RELOADING COMPILED PATTERNS</a><br>
1063<P>
1064The facilities described in this section are not available when the POSIX
1065interface to PCRE is being used, that is, when the <b>/P</b> pattern modifier is
1066specified.
1067</P>
1068<P>
1069When the POSIX interface is not in use, you can cause <b>pcretest</b> to write a
1070compiled pattern to a file, by following the modifiers with &#62; and a file name.
1071For example:
1072<pre>
1073  /pattern/im &#62;/some/file
1074</pre>
1075See the
1076<a href="pcreprecompile.html"><b>pcreprecompile</b></a>
1077documentation for a discussion about saving and re-using compiled patterns.
1078Note that if the pattern was successfully studied with JIT optimization, the
1079JIT data cannot be saved.
1080</P>
1081<P>
1082The data that is written is binary. The first eight bytes are the length of the
1083compiled pattern data followed by the length of the optional study data, each
1084written as four bytes in big-endian order (most significant byte first). If
1085there is no study data (either the pattern was not studied, or studying did not
1086return any data), the second length is zero. The lengths are followed by an
1087exact copy of the compiled pattern. If there is additional study data, this
1088(excluding any JIT data) follows immediately after the compiled pattern. After
1089writing the file, <b>pcretest</b> expects to read a new pattern.
1090</P>
1091<P>
1092A saved pattern can be reloaded into <b>pcretest</b> by specifying &#60; and a file
1093name instead of a pattern. There must be no space between &#60; and the file name,
1094which must not contain a &#60; character, as otherwise <b>pcretest</b> will
1095interpret the line as a pattern delimited by &#60; characters. For example:
1096<pre>
1097   re&#62; &#60;/some/file
1098  Compiled pattern loaded from /some/file
1099  No study data
1100</pre>
1101If the pattern was previously studied with the JIT optimization, the JIT
1102information cannot be saved and restored, and so is lost. When the pattern has
1103been loaded, <b>pcretest</b> proceeds to read data lines in the usual way.
1104</P>
1105<P>
1106You can copy a file written by <b>pcretest</b> to a different host and reload it
1107there, even if the new host has opposite endianness to the one on which the
1108pattern was compiled. For example, you can compile on an i86 machine and run on
1109a SPARC machine. When a pattern is reloaded on a host with different
1110endianness, the confirmation message is changed to:
1111<pre>
1112  Compiled pattern (byte-inverted) loaded from /some/file
1113</pre>
1114The test suite contains some saved pre-compiled patterns with different
1115endianness. These are reloaded using "&#60;!" instead of just "&#60;". This suppresses
1116the "(byte-inverted)" text so that the output is the same on all hosts. It also
1117forces debugging output once the pattern has been reloaded.
1118</P>
1119<P>
1120File names for saving and reloading can be absolute or relative, but note that
1121the shell facility of expanding a file name that starts with a tilde (~) is not
1122available.
1123</P>
1124<P>
1125The ability to save and reload files in <b>pcretest</b> is intended for testing
1126and experimentation. It is not intended for production use because only a
1127single pattern can be written to a file. Furthermore, there is no facility for
1128supplying custom character tables for use with a reloaded pattern. If the
1129original pattern was compiled with custom tables, an attempt to match a subject
1130string using a reloaded pattern is likely to cause <b>pcretest</b> to crash.
1131Finally, if you attempt to load a file that is not in the correct format, the
1132result is undefined.
1133</P>
1134<br><a name="SEC15" href="#TOC1">SEE ALSO</a><br>
1135<P>
1136<b>pcre</b>(3), <b>pcre16</b>(3), <b>pcre32</b>(3), <b>pcreapi</b>(3),
1137<b>pcrecallout</b>(3),
1138<b>pcrejit</b>, <b>pcrematching</b>(3), <b>pcrepartial</b>(d),
1139<b>pcrepattern</b>(3), <b>pcreprecompile</b>(3).
1140</P>
1141<br><a name="SEC16" href="#TOC1">AUTHOR</a><br>
1142<P>
1143Philip Hazel
1144<br>
1145University Computing Service
1146<br>
1147Cambridge CB2 3QH, England.
1148<br>
1149</P>
1150<br><a name="SEC17" href="#TOC1">REVISION</a><br>
1151<P>
1152Last updated: 09 February 2014
1153<br>
1154Copyright &copy; 1997-2014 University of Cambridge.
1155<br>
1156<p>
1157Return to the <a href="index.html">PCRE index page</a>.
1158</p>
1159