Annotation of embedaddon/pcre/doc/html/pcretest.html, revision 1.1.1.4
1.1 misho 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>
8: Return to the <a href="index.html">PCRE index page</a>.
9: </p>
10: <p>
11: This page is part of the PCRE HTML documentation. It was generated automatically
12: from the original man page. If there is any nonsense in it, please consult the
13: man page, in case the conversion went wrong.
14: <br>
15: <ul>
16: <li><a name="TOC1" href="#SEC1">SYNOPSIS</a>
1.1.1.4 ! misho 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>
1.1 misho 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
40: library itself, but it can also be used for experimenting with regular
41: expressions. This document describes the features of the test program; for
42: details of the regular expressions themselves, see the
43: <a href="pcrepattern.html"><b>pcrepattern</b></a>
44: documentation. For details of the PCRE library function calls and their
45: options, see the
46: <a href="pcreapi.html"><b>pcreapi</b></a>
1.1.1.4 ! misho 47: ,
1.1.1.2 misho 48: <a href="pcre16.html"><b>pcre16</b></a>
1.1.1.4 ! misho 49: and
! 50: <a href="pcre32.html"><b>pcre32</b></a>
! 51: documentation.
1.1 misho 52: </P>
1.1.1.4 ! misho 53: <P>
! 54: The input for <b>pcretest</b> is a sequence of regular expression patterns and
! 55: strings to be matched, as described below. The output shows the result of each
! 56: match. Options on the command line and the patterns control PCRE options and
! 57: exactly what is output.
! 58: </P>
! 59: <P>
! 60: As 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
! 62: possible feature. Some of these options are specifically designed for use in
! 63: conjunction with the test script and data files that are distributed as part of
! 64: PCRE, and are unlikely to be of use otherwise. They are all documented here,
! 65: but without much justification.
! 66: </P>
! 67: <br><a name="SEC2" href="#TOC1">INPUT DATA FORMAT</a><br>
! 68: <P>
! 69: Input to <b>pcretest</b> is processed line by line, either by calling the C
! 70: library's <b>fgets()</b> function, or via the <b>libreadline</b> library (see
! 71: below). In Unix-like environments, <b>fgets()</b> treats any bytes other than
! 72: newline 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
! 74: maximum 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>
1.1.1.2 misho 78: <P>
79: From release 8.30, two separate PCRE libraries can be built. The original one
80: supports 8-bit character strings, whereas the newer 16-bit library supports
1.1.1.4 ! misho 81: character strings encoded in 16-bit units. From release 8.32, a third library
! 82: can 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
! 84: itself still an 8-bit program, reading 8-bit input and writing 8-bit output.
! 85: When testing the 16-bit or 32-bit library, the patterns and data strings are
! 86: converted to 16- or 32-bit format before being passed to the PCRE library
! 87: functions. Results are converted to 8-bit for output.
! 88: </P>
! 89: <P>
! 90: References to functions and structures of the form <b>pcre[16|32]_xx</b> below
! 91: mean "<b>pcre_xx</b> when using the 8-bit library, <b>pcre16_xx</b> when using
! 92: the 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>
! 97: If both the 8-bit library has been built, this option causes the 8-bit library
! 98: to be used (which is the default); if the 8-bit library has not been built,
! 99: this option causes an error.
1.1.1.2 misho 100: </P>
101: <P>
1.1.1.4 ! misho 102: <b>-16</b>
! 103: If both the 8-bit or the 32-bit, and the 16-bit libraries have been built, this
! 104: option causes the 16-bit library to be used. If only the 16-bit library has been
! 105: built, this is the default (so has no effect). If only the 8-bit or the 32-bit
! 106: library has been built, this option causes an error.
1.1.1.2 misho 107: </P>
108: <P>
1.1.1.4 ! misho 109: <b>-32</b>
! 110: If both the 8-bit or the 16-bit, and the 32-bit libraries have been built, this
! 111: option causes the 32-bit library to be used. If only the 32-bit library has been
! 112: built, this is the default (so has no effect). If only the 8-bit or the 16-bit
! 113: library has been built, this option causes an error.
1.1.1.2 misho 114: </P>
1.1 misho 115: <P>
116: <b>-b</b>
117: Behave as if each pattern has the <b>/B</b> (show byte code) modifier; the
118: internal form is output after compilation.
119: </P>
120: <P>
121: <b>-C</b>
122: Output the version number of the PCRE library, and all available information
1.1.1.4 ! misho 123: about the optional features that are included, and then exit with zero exit
! 124: code. All other options are ignored.
1.1.1.2 misho 125: </P>
126: <P>
127: <b>-C</b> <i>option</i>
128: Output information about a specific build-time option, then exit. This
129: functionality is intended for use in scripts such as <b>RunTest</b>. The
1.1.1.4 ! misho 130: following options output the value and set the exit code as indicated:
1.1.1.2 misho 131: <pre>
1.1.1.4 ! misho 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
1.1.1.2 misho 138: newline the default newline setting:
139: CR, LF, CRLF, ANYCRLF, or ANY
1.1.1.4 ! misho 140: exit code is always 0
1.1.1.2 misho 141: </pre>
1.1.1.4 ! misho 142: The following options output 1 for true or 0 for false, and set the exit code
! 143: to the same value:
1.1.1.2 misho 144: <pre>
1.1.1.4 ! misho 145: ebcdic compiled for an EBCDIC environment
1.1.1.2 misho 146: jit just-in-time support is available
147: pcre16 the 16-bit library was built
1.1.1.4 ! misho 148: pcre32 the 32-bit library was built
1.1.1.2 misho 149: pcre8 the 8-bit library was built
150: ucp Unicode property support is available
1.1.1.4 ! misho 151: utf UTF-8 and/or UTF-16 and/or UTF-32 support
! 152: is available
! 153: </pre>
! 154: If an unknown option is given, an error message is output; the exit code is 0.
1.1 misho 155: </P>
156: <P>
157: <b>-d</b>
158: Behave as if each pattern has the <b>/D</b> (debug) modifier; the internal
159: form and information about the compiled pattern is output after compilation;
160: <b>-d</b> is equivalent to <b>-b -i</b>.
161: </P>
162: <P>
163: <b>-dfa</b>
164: Behave as if each data line contains the \D escape sequence; this causes the
1.1.1.4 ! misho 165: alternative matching function, <b>pcre[16|32]_dfa_exec()</b>, to be used instead
! 166: of the standard <b>pcre[16|32]_exec()</b> function (more detail is given below).
1.1 misho 167: </P>
168: <P>
169: <b>-help</b>
170: Output a brief summary these options and then exit.
171: </P>
172: <P>
173: <b>-i</b>
174: Behave as if each pattern has the <b>/I</b> modifier; information about the
175: compiled pattern is given after compilation.
176: </P>
177: <P>
178: <b>-M</b>
179: Behave as if each data line contains the \M escape sequence; this causes
180: PCRE to discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings by
1.1.1.4 ! misho 181: calling <b>pcre[16|32]_exec()</b> repeatedly with different limits.
1.1 misho 182: </P>
183: <P>
184: <b>-m</b>
185: Output the size of each compiled pattern after it has been compiled. This is
1.1.1.2 misho 186: equivalent to adding <b>/M</b> to each regular expression. The size is given in
187: bytes for both libraries.
1.1 misho 188: </P>
189: <P>
190: <b>-o</b> <i>osize</i>
191: Set the number of elements in the output vector that is used when calling
1.1.1.4 ! misho 192: <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b> to be <i>osize</i>. The
1.1.1.2 misho 193: default value is 45, which is enough for 14 capturing subexpressions for
1.1.1.4 ! misho 194: <b>pcre[16|32]_exec()</b> or 22 different matches for
! 195: <b>pcre[16|32]_dfa_exec()</b>.
1.1.1.2 misho 196: The vector size can be changed for individual matching calls by including \O
197: in the data line (see below).
1.1 misho 198: </P>
199: <P>
200: <b>-p</b>
201: Behave as if each pattern has the <b>/P</b> modifier; the POSIX wrapper API is
202: used to call PCRE. None of the other options has any effect when <b>-p</b> is
1.1.1.2 misho 203: set. This option can be used only with the 8-bit library.
1.1 misho 204: </P>
205: <P>
206: <b>-q</b>
207: Do not output the version number of <b>pcretest</b> at the start of execution.
208: </P>
209: <P>
210: <b>-S</b> <i>size</i>
211: On Unix-like systems, set the size of the run-time stack to <i>size</i>
212: megabytes.
213: </P>
214: <P>
215: <b>-s</b> or <b>-s+</b>
216: Behave as if each pattern has the <b>/S</b> modifier; in other words, force each
1.1.1.3 misho 217: pattern to be studied. If <b>-s+</b> is used, all the JIT compile options are
1.1.1.4 ! misho 218: passed to <b>pcre[16|32]_study()</b>, causing just-in-time optimization to be set
1.1.1.3 misho 219: up if it is available, for both full and partial matching. Specific JIT compile
220: options can be selected by following <b>-s+</b> with a digit in the range 1 to
221: 7, which selects the JIT compile modes as follows:
222: <pre>
223: 1 normal match only
224: 2 soft partial match only
225: 3 normal match and soft partial match
226: 4 hard partial match only
227: 6 soft and hard partial match
228: 7 all three modes (default)
229: </pre>
230: If <b>-s++</b> is used instead of <b>-s+</b> (with or without a following digit),
231: the text "(JIT)" is added to the first output line after a match or no match
232: when JIT-compiled code was actually used.
1.1.1.4 ! misho 233: <br>
! 234: <br>
! 235: Note that there are pattern options that can override <b>-s</b>, either
! 236: specifying no studying at all, or suppressing JIT compilation.
! 237: <br>
! 238: <br>
1.1.1.3 misho 239: If the <b>/I</b> or <b>/D</b> option is present on a pattern (requesting output
240: about the compiled pattern), information about the result of studying is not
241: included when studying is caused only by <b>-s</b> and neither <b>-i</b> nor
242: <b>-d</b> is present on the command line. This behaviour means that the output
243: from tests that are run with and without <b>-s</b> should be identical, except
244: when options that output information about the actual running of a match are
245: set.
1.1.1.2 misho 246: <br>
247: <br>
248: The <b>-M</b>, <b>-t</b>, and <b>-tm</b> options, which give information about
249: resources used, are likely to produce different output with and without
250: <b>-s</b>. Output may also differ if the <b>/C</b> option is present on an
251: individual pattern. This uses callouts to trace the the matching process, and
252: this may be different between studied and non-studied patterns. If the pattern
253: contains (*MARK) items there may also be differences, for the same reason. The
254: <b>-s</b> command line option can be overridden for specific patterns that
255: should never be studied (see the <b>/S</b> pattern modifier below).
1.1 misho 256: </P>
257: <P>
258: <b>-t</b>
259: Run each compile, study, and match many times with a timer, and output
260: resulting time per compile or match (in milliseconds). Do not set <b>-m</b> with
261: <b>-t</b>, because you will then get the size output a zillion times, and the
262: timing will be distorted. You can control the number of iterations that are
263: used for timing by following <b>-t</b> with a number (as a separate item on the
264: command line). For example, "-t 1000" would iterate 1000 times. The default is
265: to iterate 500000 times.
266: </P>
267: <P>
268: <b>-tm</b>
269: This is like <b>-t</b> except that it times only the matching phase, not the
270: compile or study phases.
271: </P>
1.1.1.4 ! misho 272: <br><a name="SEC5" href="#TOC1">DESCRIPTION</a><br>
1.1 misho 273: <P>
274: If <b>pcretest</b> is given two filename arguments, it reads from the first and
275: writes to the second. If it is given only one filename argument, it reads from
276: that file and writes to stdout. Otherwise, it reads from stdin and writes to
277: stdout, and prompts for each line of input, using "re>" to prompt for regular
278: expressions, and "data>" to prompt for data lines.
279: </P>
280: <P>
281: When <b>pcretest</b> is built, a configuration option can specify that it should
282: be linked with the <b>libreadline</b> library. When this is done, if the input
283: is from a terminal, it is read using the <b>readline()</b> function. This
284: provides line-editing and history facilities. The output from the <b>-help</b>
285: option states whether or not <b>readline()</b> will be used.
286: </P>
287: <P>
288: The program handles any number of sets of input on a single input file. Each
289: set starts with a regular expression, and continues with any number of data
290: lines to be matched against the pattern.
291: </P>
292: <P>
293: Each data line is matched separately and independently. If you want to do
294: multi-line matches, you have to use the \n escape sequence (or \r or \r\n,
295: etc., depending on the newline setting) in a single line of input to encode the
296: newline sequences. There is no limit on the length of data lines; the input
297: buffer is automatically extended if it is too small.
298: </P>
299: <P>
300: An empty line signals the end of the data lines, at which point a new regular
301: expression is read. The regular expressions are given enclosed in any
302: non-alphanumeric delimiters other than backslash, for example:
303: <pre>
304: /(a|bc)x+yz/
305: </pre>
306: White space before the initial delimiter is ignored. A regular expression may
307: be continued over several input lines, in which case the newline characters are
308: included within it. It is possible to include the delimiter within the pattern
309: by escaping it, for example
310: <pre>
311: /abc\/def/
312: </pre>
313: If you do so, the escape and the delimiter form part of the pattern, but since
314: delimiters are always non-alphanumeric, this does not affect its interpretation.
315: If the terminating delimiter is immediately followed by a backslash, for
316: example,
317: <pre>
318: /abc/\
319: </pre>
320: then a backslash is added to the end of the pattern. This is done to provide a
321: way of testing the error condition that arises if a pattern finishes with a
322: backslash, because
323: <pre>
324: /abc\/
325: </pre>
326: is interpreted as the first line of a pattern that starts with "abc/", causing
327: pcretest to read the next line as a continuation of the regular expression.
328: </P>
1.1.1.4 ! misho 329: <br><a name="SEC6" href="#TOC1">PATTERN MODIFIERS</a><br>
1.1 misho 330: <P>
331: A pattern may be followed by any number of modifiers, which are mostly single
1.1.1.4 ! misho 332: characters, though some of these can be qualified by further characters.
! 333: Following Perl usage, these are referred to below as, for example, "the
! 334: <b>/i</b> modifier", even though the delimiter of the pattern need not always be
! 335: a slash, and no slash is used when writing modifiers. White space may appear
! 336: between the final pattern delimiter and the first modifier, and between the
! 337: modifiers themselves. For reference, here is a complete list of modifiers. They
! 338: fall into several groups that are described in detail in the following
! 339: sections.
! 340: <pre>
! 341: <b>/8</b> set UTF mode
! 342: <b>/9</b> set PCRE_NEVER_UTF (locks out UTF mode)
! 343: <b>/?</b> disable UTF validity check
! 344: <b>/+</b> show remainder of subject after match
! 345: <b>/=</b> show all captures (not just those that are set)
! 346:
! 347: <b>/A</b> set PCRE_ANCHORED
! 348: <b>/B</b> show compiled code
! 349: <b>/C</b> set PCRE_AUTO_CALLOUT
! 350: <b>/D</b> same as <b>/B</b> plus <b>/I</b>
! 351: <b>/E</b> set PCRE_DOLLAR_ENDONLY
! 352: <b>/F</b> flip byte order in compiled pattern
! 353: <b>/f</b> set PCRE_FIRSTLINE
! 354: <b>/G</b> find all matches (shorten string)
! 355: <b>/g</b> find all matches (use startoffset)
! 356: <b>/I</b> show information about pattern
! 357: <b>/i</b> set PCRE_CASELESS
! 358: <b>/J</b> set PCRE_DUPNAMES
! 359: <b>/K</b> show backtracking control names
! 360: <b>/L</b> set locale
! 361: <b>/M</b> show compiled memory size
! 362: <b>/m</b> set PCRE_MULTILINE
! 363: <b>/N</b> set PCRE_NO_AUTO_CAPTURE
! 364: <b>/P</b> use the POSIX wrapper
! 365: <b>/S</b> study the pattern after compilation
! 366: <b>/s</b> set PCRE_DOTALL
! 367: <b>/T</b> select character tables
! 368: <b>/U</b> set PCRE_UNGREEDY
! 369: <b>/W</b> set PCRE_UCP
! 370: <b>/X</b> set PCRE_EXTRA
! 371: <b>/x</b> set PCRE_EXTENDED
! 372: <b>/Y</b> set PCRE_NO_START_OPTIMIZE
! 373: <b>/Z</b> don't show lengths in <b>/B</b> output
! 374:
! 375: <b>/<any></b> set PCRE_NEWLINE_ANY
! 376: <b>/<anycrlf></b> set PCRE_NEWLINE_ANYCRLF
! 377: <b>/<cr></b> set PCRE_NEWLINE_CR
! 378: <b>/<crlf></b> set PCRE_NEWLINE_CRLF
! 379: <b>/<lf></b> set PCRE_NEWLINE_LF
! 380: <b>/<bsr_anycrlf></b> set PCRE_BSR_ANYCRLF
! 381: <b>/<bsr_unicode></b> set PCRE_BSR_UNICODE
! 382: <b>/<JS></b> set PCRE_JAVASCRIPT_COMPAT
! 383:
! 384: </PRE>
1.1 misho 385: </P>
1.1.1.4 ! misho 386: <br><b>
! 387: Perl-compatible modifiers
! 388: </b><br>
1.1 misho 389: <P>
390: The <b>/i</b>, <b>/m</b>, <b>/s</b>, and <b>/x</b> modifiers set the PCRE_CASELESS,
391: PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when
1.1.1.4 ! misho 392: <b>pcre[16|32]_compile()</b> is called. These four modifier letters have the same
1.1 misho 393: effect as they do in Perl. For example:
394: <pre>
395: /caseless/i
1.1.1.4 ! misho 396:
! 397: </PRE>
! 398: </P>
! 399: <br><b>
! 400: Modifiers for other PCRE options
! 401: </b><br>
! 402: <P>
1.1 misho 403: The following table shows additional modifiers for setting PCRE compile-time
404: options that do not correspond to anything in Perl:
405: <pre>
1.1.1.2 misho 406: <b>/8</b> PCRE_UTF8 ) when using the 8-bit
407: <b>/?</b> PCRE_NO_UTF8_CHECK ) library
408:
409: <b>/8</b> PCRE_UTF16 ) when using the 16-bit
410: <b>/?</b> PCRE_NO_UTF16_CHECK ) library
411:
1.1.1.4 ! misho 412: <b>/8</b> PCRE_UTF32 ) when using the 32-bit
! 413: <b>/?</b> PCRE_NO_UTF32_CHECK ) library
! 414:
! 415: <b>/9</b> PCRE_NEVER_UTF
1.1 misho 416: <b>/A</b> PCRE_ANCHORED
417: <b>/C</b> PCRE_AUTO_CALLOUT
418: <b>/E</b> PCRE_DOLLAR_ENDONLY
419: <b>/f</b> PCRE_FIRSTLINE
420: <b>/J</b> PCRE_DUPNAMES
421: <b>/N</b> PCRE_NO_AUTO_CAPTURE
422: <b>/U</b> PCRE_UNGREEDY
423: <b>/W</b> PCRE_UCP
424: <b>/X</b> PCRE_EXTRA
425: <b>/Y</b> PCRE_NO_START_OPTIMIZE
1.1.1.4 ! misho 426: <b>/<any></b> PCRE_NEWLINE_ANY
! 427: <b>/<anycrlf></b> PCRE_NEWLINE_ANYCRLF
1.1 misho 428: <b>/<cr></b> PCRE_NEWLINE_CR
429: <b>/<crlf></b> PCRE_NEWLINE_CRLF
1.1.1.4 ! misho 430: <b>/<lf></b> PCRE_NEWLINE_LF
1.1 misho 431: <b>/<bsr_anycrlf></b> PCRE_BSR_ANYCRLF
432: <b>/<bsr_unicode></b> PCRE_BSR_UNICODE
1.1.1.4 ! misho 433: <b>/<JS></b> PCRE_JAVASCRIPT_COMPAT
1.1 misho 434: </pre>
435: The modifiers that are enclosed in angle brackets are literal strings as shown,
436: including the angle brackets, but the letters within can be in either case.
437: This example sets multiline matching with CRLF as the line ending sequence:
438: <pre>
439: /^abc/m<CRLF>
440: </pre>
1.1.1.4 ! misho 441: As well as turning on the PCRE_UTF8/16/32 option, the <b>/8</b> modifier causes
1.1.1.2 misho 442: all non-printing characters in output strings to be printed using the
443: \x{hh...} notation. Otherwise, those less than 0x100 are output in hex without
444: the curly brackets.
445: </P>
446: <P>
447: Full details of the PCRE options are given in the
1.1 misho 448: <a href="pcreapi.html"><b>pcreapi</b></a>
449: documentation.
450: </P>
451: <br><b>
452: Finding all matches in a string
453: </b><br>
454: <P>
455: Searching for all possible matches within each subject string can be requested
456: by the <b>/g</b> or <b>/G</b> modifier. After finding a match, PCRE is called
457: again to search the remainder of the subject string. The difference between
458: <b>/g</b> and <b>/G</b> is that the former uses the <i>startoffset</i> argument to
1.1.1.4 ! misho 459: <b>pcre[16|32]_exec()</b> to start searching at a new point within the entire
1.1.1.2 misho 460: string (which is in effect what Perl does), whereas the latter passes over a
461: shortened substring. This makes a difference to the matching process if the
462: pattern begins with a lookbehind assertion (including \b or \B).
1.1 misho 463: </P>
464: <P>
1.1.1.4 ! misho 465: If any call to <b>pcre[16|32]_exec()</b> in a <b>/g</b> or <b>/G</b> sequence matches
1.1.1.2 misho 466: an empty string, the next call is done with the PCRE_NOTEMPTY_ATSTART and
1.1 misho 467: PCRE_ANCHORED flags set in order to search for another, non-empty, match at the
468: same point. If this second match fails, the start offset is advanced, and the
469: normal match is retried. This imitates the way Perl handles such cases when
470: using the <b>/g</b> modifier or the <b>split()</b> function. Normally, the start
471: offset is advanced by one character, but if the newline convention recognizes
472: CRLF as a newline, and the current character is CR followed by LF, an advance
473: of two is used.
474: </P>
475: <br><b>
476: Other modifiers
477: </b><br>
478: <P>
479: There are yet more modifiers for controlling the way <b>pcretest</b>
480: operates.
481: </P>
482: <P>
483: The <b>/+</b> modifier requests that as well as outputting the substring that
484: matched the entire pattern, <b>pcretest</b> should in addition output the
485: remainder of the subject string. This is useful for tests where the subject
486: contains multiple copies of the same substring. If the <b>+</b> modifier appears
487: twice, the same action is taken for captured substrings. In each case the
488: remainder is output on the following line with a plus character following the
489: capture number. Note that this modifier must not immediately follow the /S
1.1.1.3 misho 490: modifier because /S+ and /S++ have other meanings.
1.1 misho 491: </P>
492: <P>
493: The <b>/=</b> modifier requests that the values of all potential captured
1.1.1.2 misho 494: parentheses be output after a match. By default, only those up to the highest
495: one actually used in the match are output (corresponding to the return code
1.1.1.4 ! misho 496: from <b>pcre[16|32]_exec()</b>). Values in the offsets vector corresponding to
1.1.1.2 misho 497: higher numbers should be set to -1, and these are output as "<unset>". This
498: modifier gives a way of checking that this is happening.
1.1 misho 499: </P>
500: <P>
501: The <b>/B</b> modifier is a debugging feature. It requests that <b>pcretest</b>
1.1.1.2 misho 502: output a representation of the compiled code after compilation. Normally this
503: information contains length and offset values; however, if <b>/Z</b> is also
504: present, this data is replaced by spaces. This is a special feature for use in
505: the automatic test scripts; it ensures that the same output is generated for
506: different internal link sizes.
1.1 misho 507: </P>
508: <P>
509: The <b>/D</b> modifier is a PCRE debugging feature, and is equivalent to
510: <b>/BI</b>, that is, both the <b>/B</b> and the <b>/I</b> modifiers.
511: </P>
512: <P>
513: The <b>/F</b> modifier causes <b>pcretest</b> to flip the byte order of the
1.1.1.2 misho 514: 2-byte and 4-byte fields in the compiled pattern. This facility is for testing
515: the feature in PCRE that allows it to execute patterns that were compiled on a
516: host with a different endianness. This feature is not available when the POSIX
517: interface to PCRE is being used, that is, when the <b>/P</b> pattern modifier is
518: specified. See also the section about saving and reloading compiled patterns
519: below.
1.1 misho 520: </P>
521: <P>
522: The <b>/I</b> modifier requests that <b>pcretest</b> output information about the
523: compiled pattern (whether it is anchored, has a fixed first character, and
1.1.1.4 ! misho 524: so on). It does this by calling <b>pcre[16|32]_fullinfo()</b> after compiling a
1.1 misho 525: pattern. If the pattern is studied, the results of that are also output.
526: </P>
527: <P>
528: The <b>/K</b> modifier requests <b>pcretest</b> to show names from backtracking
1.1.1.4 ! misho 529: control verbs that are returned from calls to <b>pcre[16|32]_exec()</b>. It causes
! 530: <b>pcretest</b> to create a <b>pcre[16|32]_extra</b> block if one has not already
! 531: been created by a call to <b>pcre[16|32]_study()</b>, and to set the
1.1.1.2 misho 532: PCRE_EXTRA_MARK flag and the <b>mark</b> field within it, every time that
1.1.1.4 ! misho 533: <b>pcre[16|32]_exec()</b> is called. If the variable that the <b>mark</b> field
1.1.1.2 misho 534: points to is non-NULL for a match, non-match, or partial match, <b>pcretest</b>
535: prints the string to which it points. For a match, this is shown on a line by
536: itself, tagged with "MK:". For a non-match it is added to the message.
1.1 misho 537: </P>
538: <P>
539: The <b>/L</b> modifier must be followed directly by the name of a locale, for
540: example,
541: <pre>
542: /pattern/Lfr_FR
543: </pre>
544: For this reason, it must be the last modifier. The given locale is set,
1.1.1.4 ! misho 545: <b>pcre[16|32]_maketables()</b> is called to build a set of character tables for
! 546: the locale, and this is then passed to <b>pcre[16|32]_compile()</b> when compiling
1.1.1.2 misho 547: the regular expression. Without an <b>/L</b> (or <b>/T</b>) modifier, NULL is
548: passed as the tables pointer; that is, <b>/L</b> applies only to the expression
549: on which it appears.
1.1 misho 550: </P>
551: <P>
1.1.1.2 misho 552: The <b>/M</b> modifier causes the size in bytes of the memory block used to hold
553: the compiled pattern to be output. This does not include the size of the
1.1.1.4 ! misho 554: <b>pcre[16|32]</b> block; it is just the actual compiled data. If the pattern is
1.1.1.2 misho 555: successfully studied with the PCRE_STUDY_JIT_COMPILE option, the size of the
556: JIT compiled code is also output.
1.1 misho 557: </P>
558: <P>
1.1.1.4 ! misho 559: The <b>/S</b> modifier causes <b>pcre[16|32]_study()</b> to be called after the
! 560: expression has been compiled, and the results used when the expression is
! 561: matched. There are a number of qualifying characters that may follow <b>/S</b>.
! 562: They may appear in any order.
! 563: </P>
! 564: <P>
! 565: If <b>S</b> is followed by an exclamation mark, <b>pcre[16|32]_study()</b> is called
! 566: with the PCRE_STUDY_EXTRA_NEEDED option, causing it always to return a
! 567: <b>pcre_extra</b> block, even when studying discovers no useful information.
! 568: </P>
! 569: <P>
! 570: If <b>/S</b> is followed by a second S character, it suppresses studying, even
1.1 misho 571: if it was requested externally by the <b>-s</b> command line option. This makes
572: it possible to specify that certain patterns are always studied, and others are
573: never studied, independently of <b>-s</b>. This feature is used in the test
574: files in a few cases where the output is different when the pattern is studied.
575: </P>
576: <P>
1.1.1.4 ! misho 577: If the <b>/S</b> modifier is followed by a + character, the call to
! 578: <b>pcre[16|32]_study()</b> is made with all the JIT study options, requesting
1.1.1.3 misho 579: just-in-time optimization support if it is available, for both normal and
580: partial matching. If you want to restrict the JIT compiling modes, you can
581: follow <b>/S+</b> with a digit in the range 1 to 7:
582: <pre>
583: 1 normal match only
584: 2 soft partial match only
585: 3 normal match and soft partial match
586: 4 hard partial match only
587: 6 soft and hard partial match
588: 7 all three modes (default)
589: </pre>
590: If <b>/S++</b> is used instead of <b>/S+</b> (with or without a following digit),
591: the text "(JIT)" is added to the first output line after a match or no match
592: when JIT-compiled code was actually used.
593: </P>
594: <P>
595: Note that there is also an independent <b>/+</b> modifier; it must not be given
596: immediately after <b>/S</b> or <b>/S+</b> because this will be misinterpreted.
597: </P>
598: <P>
599: If JIT studying is successful, the compiled JIT code will automatically be used
1.1.1.4 ! misho 600: when <b>pcre[16|32]_exec()</b> is run, except when incompatible run-time options
1.1.1.3 misho 601: are specified. For more details, see the
1.1 misho 602: <a href="pcrejit.html"><b>pcrejit</b></a>
603: documentation. See also the <b>\J</b> escape sequence below for a way of
604: setting the size of the JIT stack.
605: </P>
606: <P>
1.1.1.4 ! misho 607: Finally, if <b>/S</b> is followed by a minus character, JIT compilation is
! 608: suppressed, even if it was requested externally by the <b>-s</b> command line
! 609: option. This makes it possible to specify that JIT is never to be used for
! 610: certain patterns.
! 611: </P>
! 612: <P>
1.1 misho 613: The <b>/T</b> modifier must be followed by a single digit. It causes a specific
1.1.1.4 ! misho 614: set of built-in character tables to be passed to <b>pcre[16|32]_compile()</b>. It
1.1.1.2 misho 615: is used in the standard PCRE tests to check behaviour with different character
1.1 misho 616: tables. The digit specifies the tables as follows:
617: <pre>
618: 0 the default ASCII tables, as distributed in
619: pcre_chartables.c.dist
620: 1 a set of tables defining ISO 8859 characters
621: </pre>
622: In table 1, some characters whose codes are greater than 128 are identified as
623: letters, digits, spaces, etc.
624: </P>
625: <br><b>
626: Using the POSIX wrapper API
627: </b><br>
628: <P>
629: The <b>/P</b> modifier causes <b>pcretest</b> to call PCRE via the POSIX wrapper
1.1.1.2 misho 630: API rather than its native API. This supports only the 8-bit library. When
631: <b>/P</b> is set, the following modifiers set options for the <b>regcomp()</b>
632: function:
1.1 misho 633: <pre>
634: /i REG_ICASE
635: /m REG_NEWLINE
636: /N REG_NOSUB
637: /s REG_DOTALL )
638: /U REG_UNGREEDY ) These options are not part of
639: /W REG_UCP ) the POSIX standard
640: /8 REG_UTF8 )
641: </pre>
642: The <b>/+</b> modifier works as described above. All other modifiers are
643: ignored.
644: </P>
1.1.1.4 ! misho 645: <br><a name="SEC7" href="#TOC1">DATA LINES</a><br>
1.1 misho 646: <P>
1.1.1.4 ! misho 647: Before each data line is passed to <b>pcre[16|32]_exec()</b>, leading and trailing
1.1 misho 648: white space is removed, and it is then scanned for \ escapes. Some of these
649: are pretty esoteric features, intended for checking out some of the more
650: complicated features of PCRE. If you are just testing "ordinary" regular
651: expressions, you probably don't need any of these. The following escapes are
652: recognized:
653: <pre>
654: \a alarm (BEL, \x07)
655: \b backspace (\x08)
656: \e escape (\x27)
657: \f form feed (\x0c)
658: \n newline (\x0a)
659: \qdd set the PCRE_MATCH_LIMIT limit to dd (any number of digits)
660: \r carriage return (\x0d)
661: \t tab (\x09)
662: \v vertical tab (\x0b)
1.1.1.2 misho 663: \nnn octal character (up to 3 octal digits); always
1.1.1.4 ! misho 664: a byte unless > 255 in UTF-8 or 16-bit or 32-bit mode
1.1 misho 665: \xhh hexadecimal byte (up to 2 hex digits)
1.1.1.2 misho 666: \x{hh...} hexadecimal character (any number of hex digits)
1.1.1.4 ! misho 667: \A pass the PCRE_ANCHORED option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
! 668: \B pass the PCRE_NOTBOL option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
! 669: \Cdd call pcre[16|32]_copy_substring() for substring dd after a successful match (number less than 32)
! 670: \Cname call pcre[16|32]_copy_named_substring() for substring "name" after a successful match (name termin-
1.1 misho 671: ated by next non alphanumeric character)
672: \C+ show the current captured substrings at callout time
673: \C- do not supply a callout function
674: \C!n return 1 instead of 0 when callout number n is reached
675: \C!n!m return 1 instead of 0 when callout number n is reached for the nth time
676: \C*n pass the number n (may be negative) as callout data; this is used as the callout return value
1.1.1.4 ! misho 677: \D use the <b>pcre[16|32]_dfa_exec()</b> match function
! 678: \F only shortest match for <b>pcre[16|32]_dfa_exec()</b>
! 679: \Gdd call pcre[16|32]_get_substring() for substring dd after a successful match (number less than 32)
! 680: \Gname call pcre[16|32]_get_named_substring() for substring "name" after a successful match (name termin-
1.1 misho 681: ated by next non-alphanumeric character)
682: \Jdd set up a JIT stack of dd kilobytes maximum (any number of digits)
1.1.1.4 ! misho 683: \L call pcre[16|32]_get_substringlist() after a successful match
1.1 misho 684: \M discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings
1.1.1.4 ! misho 685: \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
1.1 misho 686: PCRE_NOTEMPTY_ATSTART option
1.1.1.4 ! misho 687: \Odd set the size of the output vector passed to <b>pcre[16|32]_exec()</b> to dd (any number of digits)
! 688: \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
1.1 misho 689: PCRE_PARTIAL_HARD option
690: \Qdd set the PCRE_MATCH_LIMIT_RECURSION limit to dd (any number of digits)
1.1.1.4 ! misho 691: \R pass the PCRE_DFA_RESTART option to <b>pcre[16|32]_dfa_exec()</b>
1.1 misho 692: \S output details of memory get/free calls during matching
1.1.1.4 ! misho 693: \Y pass the PCRE_NO_START_OPTIMIZE option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
! 694: \Z pass the PCRE_NOTEOL option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
! 695: \? 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>
1.1 misho 696: \>dd start the match at offset dd (optional "-"; then any number of digits); this sets the <i>startoffset</i>
1.1.1.4 ! misho 697: argument for <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
! 698: \<cr> pass the PCRE_NEWLINE_CR option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
! 699: \<lf> pass the PCRE_NEWLINE_LF option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
! 700: \<crlf> pass the PCRE_NEWLINE_CRLF option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
! 701: \<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
! 702: \<any> pass the PCRE_NEWLINE_ANY option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
1.1.1.2 misho 703: </pre>
704: The use of \x{hh...} is not dependent on the use of the <b>/8</b> modifier on
705: the pattern. It is recognized always. There may be any number of hexadecimal
706: digits inside the braces; invalid values provoke error messages.
707: </P>
708: <P>
709: Note that \xhh specifies one byte rather than one character in UTF-8 mode;
710: this makes it possible to construct invalid UTF-8 sequences for testing
711: purposes. On the other hand, \x{hh} is interpreted as a UTF-8 character in
712: UTF-8 mode, generating more than one byte if the value is greater than 127.
713: When testing the 8-bit library not in UTF-8 mode, \x{hh} generates one byte
714: for values less than 256, and causes an error for greater values.
715: </P>
716: <P>
717: In UTF-16 mode, all 4-digit \x{hhhh} values are accepted. This makes it
718: possible to construct invalid UTF-16 sequences for testing purposes.
1.1 misho 719: </P>
720: <P>
1.1.1.4 ! misho 721: In UTF-32 mode, all 4- to 8-digit \x{...} values are accepted. This makes it
! 722: possible to construct invalid UTF-32 sequences for testing purposes.
! 723: </P>
! 724: <P>
1.1 misho 725: The escapes that specify line ending sequences are literal strings, exactly as
726: shown. No more than one newline setting should be present in any data line.
727: </P>
728: <P>
729: A backslash followed by anything else just escapes the anything else. If
730: the very last character is a backslash, it is ignored. This gives a way of
731: passing an empty line as data, since a real empty line terminates the data
732: input.
733: </P>
734: <P>
735: The <b>\J</b> escape provides a way of setting the maximum stack size that is
736: used by the just-in-time optimization code. It is ignored if JIT optimization
737: is not being used. Providing a stack that is larger than the default 32K is
738: necessary only for very complicated patterns.
739: </P>
740: <P>
1.1.1.4 ! misho 741: If \M is present, <b>pcretest</b> calls <b>pcre[16|32]_exec()</b> several times,
1.1.1.2 misho 742: with different values in the <i>match_limit</i> and <i>match_limit_recursion</i>
1.1.1.4 ! misho 743: fields of the <b>pcre[16|32]_extra</b> data structure, until it finds the minimum
! 744: numbers for each parameter that allow <b>pcre[16|32]_exec()</b> to complete without
1.1 misho 745: error. Because this is testing a specific feature of the normal interpretive
1.1.1.4 ! misho 746: <b>pcre[16|32]_exec()</b> execution, the use of any JIT optimization that might
1.1.1.2 misho 747: have been set up by the <b>/S+</b> qualifier of <b>-s+</b> option is disabled.
1.1 misho 748: </P>
749: <P>
750: The <i>match_limit</i> number is a measure of the amount of backtracking
751: that takes place, and checking it out can be instructive. For most simple
752: matches, the number is quite small, but for patterns with very large numbers of
753: matching possibilities, it can become large very quickly with increasing length
754: of subject string. The <i>match_limit_recursion</i> number is a measure of how
755: much stack (or, if PCRE is compiled with NO_RECURSE, how much heap) memory is
756: needed to complete the match attempt.
757: </P>
758: <P>
759: When \O is used, the value specified may be higher or lower than the size set
760: by the <b>-O</b> command line option (or defaulted to 45); \O applies only to
1.1.1.4 ! misho 761: the call of <b>pcre[16|32]_exec()</b> for the line in which it appears.
1.1 misho 762: </P>
763: <P>
764: If the <b>/P</b> modifier was present on the pattern, causing the POSIX wrapper
765: API to be used, the only option-setting sequences that have any effect are \B,
766: \N, and \Z, causing REG_NOTBOL, REG_NOTEMPTY, and REG_NOTEOL, respectively,
767: to be passed to <b>regexec()</b>.
768: </P>
1.1.1.4 ! misho 769: <br><a name="SEC8" href="#TOC1">THE ALTERNATIVE MATCHING FUNCTION</a><br>
1.1 misho 770: <P>
771: By default, <b>pcretest</b> uses the standard PCRE matching function,
1.1.1.4 ! misho 772: <b>pcre[16|32]_exec()</b> to match each data line. PCRE also supports an
! 773: alternative matching function, <b>pcre[16|32]_dfa_test()</b>, which operates in a
1.1 misho 774: different way, and has some restrictions. The differences between the two
775: functions are described in the
776: <a href="pcrematching.html"><b>pcrematching</b></a>
777: documentation.
778: </P>
779: <P>
780: If a data line contains the \D escape sequence, or if the command line
1.1.1.2 misho 781: contains the <b>-dfa</b> option, the alternative matching function is used.
1.1 misho 782: This function finds all possible matches at a given point. If, however, the \F
783: escape sequence is present in the data line, it stops after the first match is
784: found. This is always the shortest possible match.
785: </P>
1.1.1.4 ! misho 786: <br><a name="SEC9" href="#TOC1">DEFAULT OUTPUT FROM PCRETEST</a><br>
1.1 misho 787: <P>
788: This section describes the output when the normal matching function,
1.1.1.4 ! misho 789: <b>pcre[16|32]_exec()</b>, is being used.
1.1 misho 790: </P>
791: <P>
792: When a match succeeds, <b>pcretest</b> outputs the list of captured substrings
1.1.1.4 ! misho 793: that <b>pcre[16|32]_exec()</b> returns, starting with number 0 for the string that
1.1 misho 794: matched the whole pattern. Otherwise, it outputs "No match" when the return is
795: PCRE_ERROR_NOMATCH, and "Partial match:" followed by the partially matching
1.1.1.4 ! misho 796: substring when <b>pcre[16|32]_exec()</b> returns PCRE_ERROR_PARTIAL. (Note that
1.1.1.2 misho 797: this is the entire substring that was inspected during the partial match; it
798: may include characters before the actual match start if a lookbehind assertion,
1.1 misho 799: \K, \b, or \B was involved.) For any other return, <b>pcretest</b> outputs
800: the PCRE negative error number and a short descriptive phrase. If the error is
1.1.1.2 misho 801: a failed UTF string check, the offset of the start of the failing character and
802: the reason code are also output, provided that the size of the output vector is
803: at least two. Here is an example of an interactive <b>pcretest</b> run.
1.1 misho 804: <pre>
805: $ pcretest
806: PCRE version 8.13 2011-04-30
807:
808: re> /^abc(\d+)/
809: data> abc123
810: 0: abc123
811: 1: 123
812: data> xyz
813: No match
814: </pre>
815: Unset capturing substrings that are not followed by one that is set are not
1.1.1.4 ! misho 816: returned by <b>pcre[16|32]_exec()</b>, and are not shown by <b>pcretest</b>. In the
1.1 misho 817: following example, there are two capturing substrings, but when the first data
818: line is matched, the second, unset substring is not shown. An "internal" unset
819: substring is shown as "<unset>", as for the second data line.
820: <pre>
821: re> /(a)|(b)/
822: data> a
823: 0: a
824: 1: a
825: data> b
826: 0: b
827: 1: <unset>
828: 2: b
829: </pre>
1.1.1.2 misho 830: If the strings contain any non-printing characters, they are output as \xhh
831: escapes if the value is less than 256 and UTF mode is not set. Otherwise they
832: are output as \x{hh...} escapes. See below for the definition of non-printing
833: characters. If the pattern has the <b>/+</b> modifier, the output for substring
834: 0 is followed by the the rest of the subject string, identified by "0+" like
835: this:
1.1 misho 836: <pre>
837: re> /cat/+
838: data> cataract
839: 0: cat
840: 0+ aract
841: </pre>
842: If the pattern has the <b>/g</b> or <b>/G</b> modifier, the results of successive
843: matching attempts are output in sequence, like this:
844: <pre>
845: re> /\Bi(\w\w)/g
846: data> Mississippi
847: 0: iss
848: 1: ss
849: 0: iss
850: 1: ss
851: 0: ipp
852: 1: pp
853: </pre>
854: "No match" is output only if the first match attempt fails. Here is an example
855: of a failure message (the offset 4 that is specified by \>4 is past the end of
856: the subject string):
857: <pre>
858: re> /xyz/
859: data> xyz\>4
860: Error -24 (bad offset value)
861: </PRE>
862: </P>
863: <P>
864: If any of the sequences <b>\C</b>, <b>\G</b>, or <b>\L</b> are present in a
865: data line that is successfully matched, the substrings extracted by the
866: convenience functions are output with C, G, or L after the string number
867: instead of a colon. This is in addition to the normal full list. The string
868: length (that is, the return from the extraction function) is given in
869: parentheses after each string for <b>\C</b> and <b>\G</b>.
870: </P>
871: <P>
872: Note that whereas patterns can be continued over several lines (a plain ">"
873: prompt is used for continuations), data lines may not. However newlines can be
874: included in data by means of the \n escape (or \r, \r\n, etc., depending on
875: the newline sequence setting).
876: </P>
1.1.1.4 ! misho 877: <br><a name="SEC10" href="#TOC1">OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION</a><br>
1.1 misho 878: <P>
1.1.1.4 ! misho 879: When the alternative matching function, <b>pcre[16|32]_dfa_exec()</b>, is used (by
1.1 misho 880: means of the \D escape sequence or the <b>-dfa</b> command line option), the
881: output consists of a list of all the matches that start at the first point in
882: the subject where there is at least one match. For example:
883: <pre>
884: re> /(tang|tangerine|tan)/
885: data> yellow tangerine\D
886: 0: tangerine
887: 1: tang
888: 2: tan
889: </pre>
890: (Using the normal matching function on this data finds only "tang".) The
891: longest matching string is always given first (and numbered zero). After a
892: PCRE_ERROR_PARTIAL return, the output is "Partial match:", followed by the
893: partially matching substring. (Note that this is the entire substring that was
894: inspected during the partial match; it may include characters before the actual
895: match start if a lookbehind assertion, \K, \b, or \B was involved.)
896: </P>
897: <P>
898: If <b>/g</b> is present on the pattern, the search for further matches resumes
899: at the end of the longest match. For example:
900: <pre>
901: re> /(tang|tangerine|tan)/g
902: data> yellow tangerine and tangy sultana\D
903: 0: tangerine
904: 1: tang
905: 2: tan
906: 0: tang
907: 1: tan
908: 0: tan
909: </pre>
910: Since the matching function does not support substring capture, the escape
911: sequences that are concerned with captured substrings are not relevant.
912: </P>
1.1.1.4 ! misho 913: <br><a name="SEC11" href="#TOC1">RESTARTING AFTER A PARTIAL MATCH</a><br>
1.1 misho 914: <P>
915: When the alternative matching function has given the PCRE_ERROR_PARTIAL return,
916: indicating that the subject partially matched the pattern, you can restart the
917: match with additional subject data by means of the \R escape sequence. For
918: example:
919: <pre>
920: re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
921: data> 23ja\P\D
922: Partial match: 23ja
923: data> n05\R\D
924: 0: n05
925: </pre>
926: For further information about partial matching, see the
927: <a href="pcrepartial.html"><b>pcrepartial</b></a>
928: documentation.
929: </P>
1.1.1.4 ! misho 930: <br><a name="SEC12" href="#TOC1">CALLOUTS</a><br>
1.1 misho 931: <P>
932: If the pattern contains any callout requests, <b>pcretest</b>'s callout function
933: is called during matching. This works with both matching functions. By default,
934: the called function displays the callout number, the start and current
935: positions in the text at the callout time, and the next pattern item to be
1.1.1.2 misho 936: tested. For example:
1.1 misho 937: <pre>
938: --->pqrabcdef
939: 0 ^ ^ \d
940: </pre>
1.1.1.2 misho 941: This output indicates that callout number 0 occurred for a match attempt
942: starting at the fourth character of the subject string, when the pointer was at
943: the seventh character of the data, and when the next pattern item was \d. Just
944: one circumflex is output if the start and current positions are the same.
1.1 misho 945: </P>
946: <P>
947: Callouts numbered 255 are assumed to be automatic callouts, inserted as a
948: result of the <b>/C</b> pattern modifier. In this case, instead of showing the
949: callout number, the offset in the pattern, preceded by a plus, is output. For
950: example:
951: <pre>
952: re> /\d?[A-E]\*/C
953: data> E*
954: --->E*
955: +0 ^ \d?
956: +3 ^ [A-E]
957: +8 ^^ \*
958: +10 ^ ^
959: 0: E*
960: </pre>
961: If a pattern contains (*MARK) items, an additional line is output whenever
962: a change of latest mark is passed to the callout function. For example:
963: <pre>
964: re> /a(*MARK:X)bc/C
965: data> abc
966: --->abc
967: +0 ^ a
968: +1 ^^ (*MARK:X)
969: +10 ^^ b
970: Latest Mark: X
971: +11 ^ ^ c
972: +12 ^ ^
973: 0: abc
974: </pre>
975: The mark changes between matching "a" and "b", but stays the same for the rest
976: of the match, so nothing more is output. If, as a result of backtracking, the
977: mark reverts to being unset, the text "<unset>" is output.
978: </P>
979: <P>
980: The callout function in <b>pcretest</b> returns zero (carry on matching) by
981: default, but you can use a \C item in a data line (as described above) to
982: change this and other parameters of the callout.
983: </P>
984: <P>
985: Inserting callouts can be helpful when using <b>pcretest</b> to check
986: complicated regular expressions. For further information about callouts, see
987: the
988: <a href="pcrecallout.html"><b>pcrecallout</b></a>
989: documentation.
990: </P>
1.1.1.4 ! misho 991: <br><a name="SEC13" href="#TOC1">NON-PRINTING CHARACTERS</a><br>
1.1 misho 992: <P>
993: When <b>pcretest</b> is outputting text in the compiled version of a pattern,
994: bytes other than 32-126 are always treated as non-printing characters are are
995: therefore shown as hex escapes.
996: </P>
997: <P>
998: When <b>pcretest</b> is outputting text that is a matched part of a subject
999: string, it behaves in the same way, unless a different locale has been set for
1000: the pattern (using the <b>/L</b> modifier). In this case, the <b>isprint()</b>
1001: function to distinguish printing and non-printing characters.
1002: </P>
1.1.1.4 ! misho 1003: <br><a name="SEC14" href="#TOC1">SAVING AND RELOADING COMPILED PATTERNS</a><br>
1.1 misho 1004: <P>
1005: The facilities described in this section are not available when the POSIX
1006: interface to PCRE is being used, that is, when the <b>/P</b> pattern modifier is
1007: specified.
1008: </P>
1009: <P>
1010: When the POSIX interface is not in use, you can cause <b>pcretest</b> to write a
1011: compiled pattern to a file, by following the modifiers with > and a file name.
1012: For example:
1013: <pre>
1014: /pattern/im >/some/file
1015: </pre>
1016: See the
1017: <a href="pcreprecompile.html"><b>pcreprecompile</b></a>
1018: documentation for a discussion about saving and re-using compiled patterns.
1019: Note that if the pattern was successfully studied with JIT optimization, the
1020: JIT data cannot be saved.
1021: </P>
1022: <P>
1023: The data that is written is binary. The first eight bytes are the length of the
1024: compiled pattern data followed by the length of the optional study data, each
1025: written as four bytes in big-endian order (most significant byte first). If
1026: there is no study data (either the pattern was not studied, or studying did not
1027: return any data), the second length is zero. The lengths are followed by an
1028: exact copy of the compiled pattern. If there is additional study data, this
1029: (excluding any JIT data) follows immediately after the compiled pattern. After
1030: writing the file, <b>pcretest</b> expects to read a new pattern.
1031: </P>
1032: <P>
1033: A saved pattern can be reloaded into <b>pcretest</b> by specifying < and a file
1034: name instead of a pattern. The name of the file must not contain a < character,
1035: as otherwise <b>pcretest</b> will interpret the line as a pattern delimited by <
1036: characters.
1037: For example:
1038: <pre>
1039: re> </some/file
1040: Compiled pattern loaded from /some/file
1041: No study data
1042: </pre>
1043: If the pattern was previously studied with the JIT optimization, the JIT
1044: information cannot be saved and restored, and so is lost. When the pattern has
1045: been loaded, <b>pcretest</b> proceeds to read data lines in the usual way.
1046: </P>
1047: <P>
1048: You can copy a file written by <b>pcretest</b> to a different host and reload it
1049: there, even if the new host has opposite endianness to the one on which the
1050: pattern was compiled. For example, you can compile on an i86 machine and run on
1.1.1.2 misho 1051: a SPARC machine. When a pattern is reloaded on a host with different
1052: endianness, the confirmation message is changed to:
1053: <pre>
1054: Compiled pattern (byte-inverted) loaded from /some/file
1055: </pre>
1056: The test suite contains some saved pre-compiled patterns with different
1057: endianness. These are reloaded using "<!" instead of just "<". This suppresses
1058: the "(byte-inverted)" text so that the output is the same on all hosts. It also
1059: forces debugging output once the pattern has been reloaded.
1.1 misho 1060: </P>
1061: <P>
1062: File names for saving and reloading can be absolute or relative, but note that
1063: the shell facility of expanding a file name that starts with a tilde (~) is not
1064: available.
1065: </P>
1066: <P>
1067: The ability to save and reload files in <b>pcretest</b> is intended for testing
1068: and experimentation. It is not intended for production use because only a
1069: single pattern can be written to a file. Furthermore, there is no facility for
1070: supplying custom character tables for use with a reloaded pattern. If the
1071: original pattern was compiled with custom tables, an attempt to match a subject
1072: string using a reloaded pattern is likely to cause <b>pcretest</b> to crash.
1073: Finally, if you attempt to load a file that is not in the correct format, the
1074: result is undefined.
1075: </P>
1.1.1.4 ! misho 1076: <br><a name="SEC15" href="#TOC1">SEE ALSO</a><br>
1.1 misho 1077: <P>
1.1.1.4 ! misho 1078: <b>pcre</b>(3), <b>pcre16</b>(3), <b>pcre32</b>(3), <b>pcreapi</b>(3),
! 1079: <b>pcrecallout</b>(3),
1.1.1.2 misho 1080: <b>pcrejit</b>, <b>pcrematching</b>(3), <b>pcrepartial</b>(d),
1081: <b>pcrepattern</b>(3), <b>pcreprecompile</b>(3).
1.1 misho 1082: </P>
1.1.1.4 ! misho 1083: <br><a name="SEC16" href="#TOC1">AUTHOR</a><br>
1.1 misho 1084: <P>
1085: Philip Hazel
1086: <br>
1087: University Computing Service
1088: <br>
1089: Cambridge CB2 3QH, England.
1090: <br>
1091: </P>
1.1.1.4 ! misho 1092: <br><a name="SEC17" href="#TOC1">REVISION</a><br>
1.1 misho 1093: <P>
1.1.1.4 ! misho 1094: Last updated: 26 April 2013
1.1 misho 1095: <br>
1.1.1.4 ! misho 1096: Copyright © 1997-2013 University of Cambridge.
1.1 misho 1097: <br>
1098: <p>
1099: Return to the <a href="index.html">PCRE index page</a>.
1100: </p>
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