Annotation of embedaddon/pcre/doc/pcretest.1, revision 1.1.1.2
1.1 misho 1: .TH PCRETEST 1
2: .SH NAME
3: pcretest - a program for testing Perl-compatible regular expressions.
4: .SH SYNOPSIS
5: .rs
6: .sp
7: .B pcretest "[options] [input file [output file]]"
8: .sp
9: \fBpcretest\fP was written as a test program for the PCRE regular expression
10: library itself, but it can also be used for experimenting with regular
11: expressions. This document describes the features of the test program; for
12: details of the regular expressions themselves, see the
13: .\" HREF
14: \fBpcrepattern\fP
15: .\"
16: documentation. For details of the PCRE library function calls and their
17: options, see the
18: .\" HREF
19: \fBpcreapi\fP
20: .\"
1.1.1.2 ! misho 21: and
! 22: .\" HREF
! 23: \fBpcre16\fP
! 24: .\"
1.1 misho 25: documentation. The input for \fBpcretest\fP is a sequence of regular expression
26: patterns and strings to be matched, as described below. The output shows the
27: result of each match. Options on the command line and the patterns control PCRE
28: options and exactly what is output.
29: .
30: .
1.1.1.2 ! misho 31: .SH "PCRE's 8-BIT and 16-BIT LIBRARIES"
! 32: .rs
! 33: .sp
! 34: From release 8.30, two separate PCRE libraries can be built. The original one
! 35: supports 8-bit character strings, whereas the newer 16-bit library supports
! 36: character strings encoded in 16-bit units. The \fBpcretest\fP program can be
! 37: used to test both libraries. However, it is itself still an 8-bit program,
! 38: reading 8-bit input and writing 8-bit output. When testing the 16-bit library,
! 39: the patterns and data strings are converted to 16-bit format before being
! 40: passed to the PCRE library functions. Results are converted to 8-bit for
! 41: output.
! 42: .P
! 43: References to functions and structures of the form \fBpcre[16]_xx\fP below
! 44: mean "\fBpcre_xx\fP when using the 8-bit library or \fBpcre16_xx\fP when using
! 45: the 16-bit library".
! 46: .
! 47: .
! 48: .SH "COMMAND LINE OPTIONS"
1.1 misho 49: .rs
50: .TP 10
1.1.1.2 ! misho 51: \fB-16\fP
! 52: If both the 8-bit and the 16-bit libraries have been built, this option causes
! 53: the 16-bit library to be used. If only the 16-bit library has been built, this
! 54: is the default (so has no effect). If only the 8-bit library has been built,
! 55: this option causes an error.
! 56: .TP 10
1.1 misho 57: \fB-b\fP
58: Behave as if each pattern has the \fB/B\fP (show byte code) modifier; the
59: internal form is output after compilation.
60: .TP 10
61: \fB-C\fP
62: Output the version number of the PCRE library, and all available information
1.1.1.2 ! misho 63: about the optional features that are included, and then exit. All other options
! 64: are ignored.
! 65: .TP 10
! 66: \fB-C\fP \fIoption\fP
! 67: Output information about a specific build-time option, then exit. This
! 68: functionality is intended for use in scripts such as \fBRunTest\fP. The
! 69: following options output the value indicated:
! 70: .sp
! 71: linksize the internal link size (2, 3, or 4)
! 72: newline the default newline setting:
! 73: CR, LF, CRLF, ANYCRLF, or ANY
! 74: .sp
! 75: The following options output 1 for true or zero for false:
! 76: .sp
! 77: jit just-in-time support is available
! 78: pcre16 the 16-bit library was built
! 79: pcre8 the 8-bit library was built
! 80: ucp Unicode property support is available
! 81: utf UTF-8 and/or UTF-16 support is available
1.1 misho 82: .TP 10
83: \fB-d\fP
84: Behave as if each pattern has the \fB/D\fP (debug) modifier; the internal
85: form and information about the compiled pattern is output after compilation;
86: \fB-d\fP is equivalent to \fB-b -i\fP.
87: .TP 10
88: \fB-dfa\fP
89: Behave as if each data line contains the \eD escape sequence; this causes the
1.1.1.2 ! misho 90: alternative matching function, \fBpcre[16]_dfa_exec()\fP, to be used instead of
! 91: the standard \fBpcre[16]_exec()\fP function (more detail is given below).
1.1 misho 92: .TP 10
93: \fB-help\fP
94: Output a brief summary these options and then exit.
95: .TP 10
96: \fB-i\fP
97: Behave as if each pattern has the \fB/I\fP modifier; information about the
98: compiled pattern is given after compilation.
99: .TP 10
100: \fB-M\fP
101: Behave as if each data line contains the \eM escape sequence; this causes
102: PCRE to discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings by
1.1.1.2 ! misho 103: calling \fBpcre[16]_exec()\fP repeatedly with different limits.
1.1 misho 104: .TP 10
105: \fB-m\fP
106: Output the size of each compiled pattern after it has been compiled. This is
1.1.1.2 ! misho 107: equivalent to adding \fB/M\fP to each regular expression. The size is given in
! 108: bytes for both libraries.
1.1 misho 109: .TP 10
110: \fB-o\fP \fIosize\fP
111: Set the number of elements in the output vector that is used when calling
1.1.1.2 ! misho 112: \fBpcre[16]_exec()\fP or \fBpcre[16]_dfa_exec()\fP to be \fIosize\fP. The
! 113: default value is 45, which is enough for 14 capturing subexpressions for
! 114: \fBpcre[16]_exec()\fP or 22 different matches for \fBpcre[16]_dfa_exec()\fP.
! 115: The vector size can be changed for individual matching calls by including \eO
! 116: in the data line (see below).
1.1 misho 117: .TP 10
118: \fB-p\fP
119: Behave as if each pattern has the \fB/P\fP modifier; the POSIX wrapper API is
120: used to call PCRE. None of the other options has any effect when \fB-p\fP is
1.1.1.2 ! misho 121: set. This option can be used only with the 8-bit library.
1.1 misho 122: .TP 10
123: \fB-q\fP
124: Do not output the version number of \fBpcretest\fP at the start of execution.
125: .TP 10
126: \fB-S\fP \fIsize\fP
127: On Unix-like systems, set the size of the run-time stack to \fIsize\fP
128: megabytes.
129: .TP 10
130: \fB-s\fP or \fB-s+\fP
131: Behave as if each pattern has the \fB/S\fP modifier; in other words, force each
132: pattern to be studied. If \fB-s+\fP is used, the PCRE_STUDY_JIT_COMPILE flag is
1.1.1.2 ! misho 133: passed to \fBpcre[16]_study()\fP, causing just-in-time optimization to be set
! 134: up if it is available. If the \fB/I\fP or \fB/D\fP option is present on a
! 135: pattern (requesting output about the compiled pattern), information about the
! 136: result of studying is not included when studying is caused only by \fB-s\fP and
! 137: neither \fB-i\fP nor \fB-d\fP is present on the command line. This behaviour
! 138: means that the output from tests that are run with and without \fB-s\fP should
! 139: be identical, except when options that output information about the actual
! 140: running of a match are set.
! 141: .sp
! 142: The \fB-M\fP, \fB-t\fP, and \fB-tm\fP options, which give information about
! 143: resources used, are likely to produce different output with and without
! 144: \fB-s\fP. Output may also differ if the \fB/C\fP option is present on an
! 145: individual pattern. This uses callouts to trace the the matching process, and
! 146: this may be different between studied and non-studied patterns. If the pattern
! 147: contains (*MARK) items there may also be differences, for the same reason. The
! 148: \fB-s\fP command line option can be overridden for specific patterns that
! 149: should never be studied (see the \fB/S\fP pattern modifier below).
1.1 misho 150: .TP 10
151: \fB-t\fP
152: Run each compile, study, and match many times with a timer, and output
153: resulting time per compile or match (in milliseconds). Do not set \fB-m\fP with
154: \fB-t\fP, because you will then get the size output a zillion times, and the
155: timing will be distorted. You can control the number of iterations that are
156: used for timing by following \fB-t\fP with a number (as a separate item on the
157: command line). For example, "-t 1000" would iterate 1000 times. The default is
158: to iterate 500000 times.
159: .TP 10
160: \fB-tm\fP
161: This is like \fB-t\fP except that it times only the matching phase, not the
162: compile or study phases.
163: .
164: .
165: .SH DESCRIPTION
166: .rs
167: .sp
168: If \fBpcretest\fP is given two filename arguments, it reads from the first and
169: writes to the second. If it is given only one filename argument, it reads from
170: that file and writes to stdout. Otherwise, it reads from stdin and writes to
171: stdout, and prompts for each line of input, using "re>" to prompt for regular
172: expressions, and "data>" to prompt for data lines.
173: .P
174: When \fBpcretest\fP is built, a configuration option can specify that it should
175: be linked with the \fBlibreadline\fP library. When this is done, if the input
176: is from a terminal, it is read using the \fBreadline()\fP function. This
177: provides line-editing and history facilities. The output from the \fB-help\fP
178: option states whether or not \fBreadline()\fP will be used.
179: .P
180: The program handles any number of sets of input on a single input file. Each
181: set starts with a regular expression, and continues with any number of data
182: lines to be matched against the pattern.
183: .P
184: Each data line is matched separately and independently. If you want to do
185: multi-line matches, you have to use the \en escape sequence (or \er or \er\en,
186: etc., depending on the newline setting) in a single line of input to encode the
187: newline sequences. There is no limit on the length of data lines; the input
188: buffer is automatically extended if it is too small.
189: .P
190: An empty line signals the end of the data lines, at which point a new regular
191: expression is read. The regular expressions are given enclosed in any
192: non-alphanumeric delimiters other than backslash, for example:
193: .sp
194: /(a|bc)x+yz/
195: .sp
196: White space before the initial delimiter is ignored. A regular expression may
197: be continued over several input lines, in which case the newline characters are
198: included within it. It is possible to include the delimiter within the pattern
199: by escaping it, for example
200: .sp
201: /abc\e/def/
202: .sp
203: If you do so, the escape and the delimiter form part of the pattern, but since
204: delimiters are always non-alphanumeric, this does not affect its interpretation.
205: If the terminating delimiter is immediately followed by a backslash, for
206: example,
207: .sp
208: /abc/\e
209: .sp
210: then a backslash is added to the end of the pattern. This is done to provide a
211: way of testing the error condition that arises if a pattern finishes with a
212: backslash, because
213: .sp
214: /abc\e/
215: .sp
216: is interpreted as the first line of a pattern that starts with "abc/", causing
217: pcretest to read the next line as a continuation of the regular expression.
218: .
219: .
220: .SH "PATTERN MODIFIERS"
221: .rs
222: .sp
223: A pattern may be followed by any number of modifiers, which are mostly single
224: characters. Following Perl usage, these are referred to below as, for example,
225: "the \fB/i\fP modifier", even though the delimiter of the pattern need not
226: always be a slash, and no slash is used when writing modifiers. White space may
227: appear between the final pattern delimiter and the first modifier, and between
228: the modifiers themselves.
229: .P
230: The \fB/i\fP, \fB/m\fP, \fB/s\fP, and \fB/x\fP modifiers set the PCRE_CASELESS,
231: PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when
1.1.1.2 ! misho 232: \fBpcre[16]_compile()\fP is called. These four modifier letters have the same
1.1 misho 233: effect as they do in Perl. For example:
234: .sp
235: /caseless/i
236: .sp
237: The following table shows additional modifiers for setting PCRE compile-time
238: options that do not correspond to anything in Perl:
239: .sp
1.1.1.2 ! misho 240: \fB/8\fP PCRE_UTF8 ) when using the 8-bit
! 241: \fB/?\fP PCRE_NO_UTF8_CHECK ) library
! 242: .sp
! 243: \fB/8\fP PCRE_UTF16 ) when using the 16-bit
! 244: \fB/?\fP PCRE_NO_UTF16_CHECK ) library
! 245: .sp
1.1 misho 246: \fB/A\fP PCRE_ANCHORED
247: \fB/C\fP PCRE_AUTO_CALLOUT
248: \fB/E\fP PCRE_DOLLAR_ENDONLY
249: \fB/f\fP PCRE_FIRSTLINE
250: \fB/J\fP PCRE_DUPNAMES
251: \fB/N\fP PCRE_NO_AUTO_CAPTURE
252: \fB/U\fP PCRE_UNGREEDY
253: \fB/W\fP PCRE_UCP
254: \fB/X\fP PCRE_EXTRA
255: \fB/Y\fP PCRE_NO_START_OPTIMIZE
256: \fB/<JS>\fP PCRE_JAVASCRIPT_COMPAT
257: \fB/<cr>\fP PCRE_NEWLINE_CR
258: \fB/<lf>\fP PCRE_NEWLINE_LF
259: \fB/<crlf>\fP PCRE_NEWLINE_CRLF
260: \fB/<anycrlf>\fP PCRE_NEWLINE_ANYCRLF
261: \fB/<any>\fP PCRE_NEWLINE_ANY
262: \fB/<bsr_anycrlf>\fP PCRE_BSR_ANYCRLF
263: \fB/<bsr_unicode>\fP PCRE_BSR_UNICODE
264: .sp
265: The modifiers that are enclosed in angle brackets are literal strings as shown,
266: including the angle brackets, but the letters within can be in either case.
267: This example sets multiline matching with CRLF as the line ending sequence:
268: .sp
269: /^abc/m<CRLF>
270: .sp
1.1.1.2 ! misho 271: As well as turning on the PCRE_UTF8/16 option, the \fB/8\fP modifier causes
! 272: all non-printing characters in output strings to be printed using the
! 273: \ex{hh...} notation. Otherwise, those less than 0x100 are output in hex without
! 274: the curly brackets.
! 275: .P
! 276: Full details of the PCRE options are given in the
1.1 misho 277: .\" HREF
278: \fBpcreapi\fP
279: .\"
280: documentation.
281: .
282: .
283: .SS "Finding all matches in a string"
284: .rs
285: .sp
286: Searching for all possible matches within each subject string can be requested
287: by the \fB/g\fP or \fB/G\fP modifier. After finding a match, PCRE is called
288: again to search the remainder of the subject string. The difference between
289: \fB/g\fP and \fB/G\fP is that the former uses the \fIstartoffset\fP argument to
1.1.1.2 ! misho 290: \fBpcre[16]_exec()\fP to start searching at a new point within the entire
! 291: string (which is in effect what Perl does), whereas the latter passes over a
! 292: shortened substring. This makes a difference to the matching process if the
! 293: pattern begins with a lookbehind assertion (including \eb or \eB).
1.1 misho 294: .P
1.1.1.2 ! misho 295: If any call to \fBpcre[16]_exec()\fP in a \fB/g\fP or \fB/G\fP sequence matches
! 296: an empty string, the next call is done with the PCRE_NOTEMPTY_ATSTART and
1.1 misho 297: PCRE_ANCHORED flags set in order to search for another, non-empty, match at the
298: same point. If this second match fails, the start offset is advanced, and the
299: normal match is retried. This imitates the way Perl handles such cases when
300: using the \fB/g\fP modifier or the \fBsplit()\fP function. Normally, the start
301: offset is advanced by one character, but if the newline convention recognizes
302: CRLF as a newline, and the current character is CR followed by LF, an advance
303: of two is used.
304: .
305: .
306: .SS "Other modifiers"
307: .rs
308: .sp
309: There are yet more modifiers for controlling the way \fBpcretest\fP
310: operates.
311: .P
312: The \fB/+\fP modifier requests that as well as outputting the substring that
313: matched the entire pattern, \fBpcretest\fP should in addition output the
314: remainder of the subject string. This is useful for tests where the subject
315: contains multiple copies of the same substring. If the \fB+\fP modifier appears
316: twice, the same action is taken for captured substrings. In each case the
317: remainder is output on the following line with a plus character following the
318: capture number. Note that this modifier must not immediately follow the /S
319: modifier because /S+ has another meaning.
320: .P
321: The \fB/=\fP modifier requests that the values of all potential captured
1.1.1.2 ! misho 322: parentheses be output after a match. By default, only those up to the highest
! 323: one actually used in the match are output (corresponding to the return code
! 324: from \fBpcre[16]_exec()\fP). Values in the offsets vector corresponding to
! 325: higher numbers should be set to -1, and these are output as "<unset>". This
! 326: modifier gives a way of checking that this is happening.
1.1 misho 327: .P
328: The \fB/B\fP modifier is a debugging feature. It requests that \fBpcretest\fP
1.1.1.2 ! misho 329: output a representation of the compiled code after compilation. Normally this
! 330: information contains length and offset values; however, if \fB/Z\fP is also
! 331: present, this data is replaced by spaces. This is a special feature for use in
! 332: the automatic test scripts; it ensures that the same output is generated for
! 333: different internal link sizes.
1.1 misho 334: .P
335: The \fB/D\fP modifier is a PCRE debugging feature, and is equivalent to
336: \fB/BI\fP, that is, both the \fB/B\fP and the \fB/I\fP modifiers.
337: .P
338: The \fB/F\fP modifier causes \fBpcretest\fP to flip the byte order of the
1.1.1.2 ! misho 339: 2-byte and 4-byte fields in the compiled pattern. This facility is for testing
! 340: the feature in PCRE that allows it to execute patterns that were compiled on a
! 341: host with a different endianness. This feature is not available when the POSIX
! 342: interface to PCRE is being used, that is, when the \fB/P\fP pattern modifier is
! 343: specified. See also the section about saving and reloading compiled patterns
! 344: below.
1.1 misho 345: .P
346: The \fB/I\fP modifier requests that \fBpcretest\fP output information about the
347: compiled pattern (whether it is anchored, has a fixed first character, and
1.1.1.2 ! misho 348: so on). It does this by calling \fBpcre[16]_fullinfo()\fP after compiling a
1.1 misho 349: pattern. If the pattern is studied, the results of that are also output.
350: .P
351: The \fB/K\fP modifier requests \fBpcretest\fP to show names from backtracking
1.1.1.2 ! misho 352: control verbs that are returned from calls to \fBpcre[16]_exec()\fP. It causes
! 353: \fBpcretest\fP to create a \fBpcre[16]_extra\fP block if one has not already
! 354: been created by a call to \fBpcre[16]_study()\fP, and to set the
! 355: PCRE_EXTRA_MARK flag and the \fBmark\fP field within it, every time that
! 356: \fBpcre[16]_exec()\fP is called. If the variable that the \fBmark\fP field
! 357: points to is non-NULL for a match, non-match, or partial match, \fBpcretest\fP
! 358: prints the string to which it points. For a match, this is shown on a line by
! 359: itself, tagged with "MK:". For a non-match it is added to the message.
1.1 misho 360: .P
361: The \fB/L\fP modifier must be followed directly by the name of a locale, for
362: example,
363: .sp
364: /pattern/Lfr_FR
365: .sp
366: For this reason, it must be the last modifier. The given locale is set,
1.1.1.2 ! misho 367: \fBpcre[16]_maketables()\fP is called to build a set of character tables for
! 368: the locale, and this is then passed to \fBpcre[16]_compile()\fP when compiling
! 369: the regular expression. Without an \fB/L\fP (or \fB/T\fP) modifier, NULL is
! 370: passed as the tables pointer; that is, \fB/L\fP applies only to the expression
! 371: on which it appears.
! 372: .P
! 373: The \fB/M\fP modifier causes the size in bytes of the memory block used to hold
! 374: the compiled pattern to be output. This does not include the size of the
! 375: \fBpcre[16]\fP block; it is just the actual compiled data. If the pattern is
! 376: successfully studied with the PCRE_STUDY_JIT_COMPILE option, the size of the
! 377: JIT compiled code is also output.
1.1 misho 378: .P
1.1.1.2 ! misho 379: If the \fB/S\fP modifier appears once, it causes \fBpcre[16]_study()\fP to be
1.1 misho 380: called after the expression has been compiled, and the results used when the
381: expression is matched. If \fB/S\fP appears twice, it suppresses studying, even
382: if it was requested externally by the \fB-s\fP command line option. This makes
383: it possible to specify that certain patterns are always studied, and others are
384: never studied, independently of \fB-s\fP. This feature is used in the test
385: files in a few cases where the output is different when the pattern is studied.
386: .P
387: If the \fB/S\fP modifier is immediately followed by a + character, the call to
1.1.1.2 ! misho 388: \fBpcre[16]_study()\fP is made with the PCRE_STUDY_JIT_COMPILE option,
! 389: requesting just-in-time optimization support if it is available. Note that
! 390: there is also a \fB/+\fP modifier; it must not be given immediately after
! 391: \fB/S\fP because this will be misinterpreted. If JIT studying is successful, it
! 392: will automatically be used when \fBpcre[16]_exec()\fP is run, except when
! 393: incompatible run-time options are specified. These include the partial matching
! 394: options; a complete list is given in the
1.1 misho 395: .\" HREF
396: \fBpcrejit\fP
397: .\"
398: documentation. See also the \fB\eJ\fP escape sequence below for a way of
399: setting the size of the JIT stack.
400: .P
401: The \fB/T\fP modifier must be followed by a single digit. It causes a specific
1.1.1.2 ! misho 402: set of built-in character tables to be passed to \fBpcre[16]_compile()\fP. It
! 403: is used in the standard PCRE tests to check behaviour with different character
1.1 misho 404: tables. The digit specifies the tables as follows:
405: .sp
406: 0 the default ASCII tables, as distributed in
407: pcre_chartables.c.dist
408: 1 a set of tables defining ISO 8859 characters
409: .sp
410: In table 1, some characters whose codes are greater than 128 are identified as
411: letters, digits, spaces, etc.
412: .
413: .
414: .SS "Using the POSIX wrapper API"
415: .rs
416: .sp
417: The \fB/P\fP modifier causes \fBpcretest\fP to call PCRE via the POSIX wrapper
1.1.1.2 ! misho 418: API rather than its native API. This supports only the 8-bit library. When
! 419: \fB/P\fP is set, the following modifiers set options for the \fBregcomp()\fP
! 420: function:
1.1 misho 421: .sp
422: /i REG_ICASE
423: /m REG_NEWLINE
424: /N REG_NOSUB
425: /s REG_DOTALL )
426: /U REG_UNGREEDY ) These options are not part of
427: /W REG_UCP ) the POSIX standard
428: /8 REG_UTF8 )
429: .sp
430: The \fB/+\fP modifier works as described above. All other modifiers are
431: ignored.
432: .
433: .
434: .SH "DATA LINES"
435: .rs
436: .sp
1.1.1.2 ! misho 437: Before each data line is passed to \fBpcre[16]_exec()\fP, leading and trailing
1.1 misho 438: white space is removed, and it is then scanned for \e escapes. Some of these
439: are pretty esoteric features, intended for checking out some of the more
440: complicated features of PCRE. If you are just testing "ordinary" regular
441: expressions, you probably don't need any of these. The following escapes are
442: recognized:
443: .sp
444: \ea alarm (BEL, \ex07)
445: \eb backspace (\ex08)
446: \ee escape (\ex27)
447: \ef form feed (\ex0c)
448: \en newline (\ex0a)
449: .\" JOIN
450: \eqdd set the PCRE_MATCH_LIMIT limit to dd
451: (any number of digits)
452: \er carriage return (\ex0d)
453: \et tab (\ex09)
454: \ev vertical tab (\ex0b)
1.1.1.2 ! misho 455: \ennn octal character (up to 3 octal digits); always
! 456: a byte unless > 255 in UTF-8 or 16-bit mode
1.1 misho 457: \exhh hexadecimal byte (up to 2 hex digits)
1.1.1.2 ! misho 458: \ex{hh...} hexadecimal character (any number of hex digits)
1.1 misho 459: .\" JOIN
1.1.1.2 ! misho 460: \eA pass the PCRE_ANCHORED option to \fBpcre[16]_exec()\fP
! 461: or \fBpcre[16]_dfa_exec()\fP
1.1 misho 462: .\" JOIN
1.1.1.2 ! misho 463: \eB pass the PCRE_NOTBOL option to \fBpcre[16]_exec()\fP
! 464: or \fBpcre[16]_dfa_exec()\fP
1.1 misho 465: .\" JOIN
1.1.1.2 ! misho 466: \eCdd call pcre[16]_copy_substring() for substring dd
1.1 misho 467: after a successful match (number less than 32)
468: .\" JOIN
1.1.1.2 ! misho 469: \eCname call pcre[16]_copy_named_substring() for substring
1.1 misho 470: "name" after a successful match (name termin-
471: ated by next non alphanumeric character)
472: .\" JOIN
473: \eC+ show the current captured substrings at callout
474: time
475: \eC- do not supply a callout function
476: .\" JOIN
477: \eC!n return 1 instead of 0 when callout number n is
478: reached
479: .\" JOIN
480: \eC!n!m return 1 instead of 0 when callout number n is
481: reached for the nth time
482: .\" JOIN
483: \eC*n pass the number n (may be negative) as callout
484: data; this is used as the callout return value
1.1.1.2 ! misho 485: \eD use the \fBpcre[16]_dfa_exec()\fP match function
! 486: \eF only shortest match for \fBpcre[16]_dfa_exec()\fP
1.1 misho 487: .\" JOIN
1.1.1.2 ! misho 488: \eGdd call pcre[16]_get_substring() for substring dd
1.1 misho 489: after a successful match (number less than 32)
490: .\" JOIN
1.1.1.2 ! misho 491: \eGname call pcre[16]_get_named_substring() for substring
1.1 misho 492: "name" after a successful match (name termin-
493: ated by next non-alphanumeric character)
494: .\" JOIN
495: \eJdd set up a JIT stack of dd kilobytes maximum (any
496: number of digits)
497: .\" JOIN
1.1.1.2 ! misho 498: \eL call pcre[16]_get_substringlist() after a
1.1 misho 499: successful match
500: .\" JOIN
501: \eM discover the minimum MATCH_LIMIT and
502: MATCH_LIMIT_RECURSION settings
503: .\" JOIN
1.1.1.2 ! misho 504: \eN pass the PCRE_NOTEMPTY option to \fBpcre[16]_exec()\fP
! 505: or \fBpcre[16]_dfa_exec()\fP; if used twice, pass the
1.1 misho 506: PCRE_NOTEMPTY_ATSTART option
507: .\" JOIN
508: \eOdd set the size of the output vector passed to
1.1.1.2 ! misho 509: \fBpcre[16]_exec()\fP to dd (any number of digits)
1.1 misho 510: .\" JOIN
1.1.1.2 ! misho 511: \eP pass the PCRE_PARTIAL_SOFT option to \fBpcre[16]_exec()\fP
! 512: or \fBpcre[16]_dfa_exec()\fP; if used twice, pass the
1.1 misho 513: PCRE_PARTIAL_HARD option
514: .\" JOIN
515: \eQdd set the PCRE_MATCH_LIMIT_RECURSION limit to dd
516: (any number of digits)
1.1.1.2 ! misho 517: \eR pass the PCRE_DFA_RESTART option to \fBpcre[16]_dfa_exec()\fP
1.1 misho 518: \eS output details of memory get/free calls during matching
519: .\" JOIN
1.1.1.2 ! misho 520: \eY pass the PCRE_NO_START_OPTIMIZE option to \fBpcre[16]_exec()\fP
! 521: or \fBpcre[16]_dfa_exec()\fP
1.1 misho 522: .\" JOIN
1.1.1.2 ! misho 523: \eZ pass the PCRE_NOTEOL option to \fBpcre[16]_exec()\fP
! 524: or \fBpcre[16]_dfa_exec()\fP
1.1 misho 525: .\" JOIN
1.1.1.2 ! misho 526: \e? pass the PCRE_NO_UTF[8|16]_CHECK option to
! 527: \fBpcre[16]_exec()\fP or \fBpcre[16]_dfa_exec()\fP
1.1 misho 528: .\" JOIN
529: \e>dd start the match at offset dd (optional "-"; then
530: any number of digits); this sets the \fIstartoffset\fP
1.1.1.2 ! misho 531: argument for \fBpcre[16]_exec()\fP or \fBpcre[16]_dfa_exec()\fP
1.1 misho 532: .\" JOIN
1.1.1.2 ! misho 533: \e<cr> pass the PCRE_NEWLINE_CR option to \fBpcre[16]_exec()\fP
! 534: or \fBpcre[16]_dfa_exec()\fP
1.1 misho 535: .\" JOIN
1.1.1.2 ! misho 536: \e<lf> pass the PCRE_NEWLINE_LF option to \fBpcre[16]_exec()\fP
! 537: or \fBpcre[16]_dfa_exec()\fP
1.1 misho 538: .\" JOIN
1.1.1.2 ! misho 539: \e<crlf> pass the PCRE_NEWLINE_CRLF option to \fBpcre[16]_exec()\fP
! 540: or \fBpcre[16]_dfa_exec()\fP
1.1 misho 541: .\" JOIN
1.1.1.2 ! misho 542: \e<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to \fBpcre[16]_exec()\fP
! 543: or \fBpcre[16]_dfa_exec()\fP
1.1 misho 544: .\" JOIN
1.1.1.2 ! misho 545: \e<any> pass the PCRE_NEWLINE_ANY option to \fBpcre[16]_exec()\fP
! 546: or \fBpcre[16]_dfa_exec()\fP
1.1 misho 547: .sp
1.1.1.2 ! misho 548: The use of \ex{hh...} is not dependent on the use of the \fB/8\fP modifier on
! 549: the pattern. It is recognized always. There may be any number of hexadecimal
! 550: digits inside the braces; invalid values provoke error messages.
! 551: .P
! 552: Note that \exhh specifies one byte rather than one character in UTF-8 mode;
! 553: this makes it possible to construct invalid UTF-8 sequences for testing
! 554: purposes. On the other hand, \ex{hh} is interpreted as a UTF-8 character in
! 555: UTF-8 mode, generating more than one byte if the value is greater than 127.
! 556: When testing the 8-bit library not in UTF-8 mode, \ex{hh} generates one byte
! 557: for values less than 256, and causes an error for greater values.
! 558: .P
! 559: In UTF-16 mode, all 4-digit \ex{hhhh} values are accepted. This makes it
! 560: possible to construct invalid UTF-16 sequences for testing purposes.
1.1 misho 561: .P
562: The escapes that specify line ending sequences are literal strings, exactly as
563: shown. No more than one newline setting should be present in any data line.
564: .P
565: A backslash followed by anything else just escapes the anything else. If
566: the very last character is a backslash, it is ignored. This gives a way of
567: passing an empty line as data, since a real empty line terminates the data
568: input.
569: .P
570: The \fB\eJ\fP escape provides a way of setting the maximum stack size that is
571: used by the just-in-time optimization code. It is ignored if JIT optimization
572: is not being used. Providing a stack that is larger than the default 32K is
573: necessary only for very complicated patterns.
574: .P
1.1.1.2 ! misho 575: If \eM is present, \fBpcretest\fP calls \fBpcre[16]_exec()\fP several times,
! 576: with different values in the \fImatch_limit\fP and \fImatch_limit_recursion\fP
! 577: fields of the \fBpcre[16]_extra\fP data structure, until it finds the minimum
! 578: numbers for each parameter that allow \fBpcre[16]_exec()\fP to complete without
1.1 misho 579: error. Because this is testing a specific feature of the normal interpretive
1.1.1.2 ! misho 580: \fBpcre[16]_exec()\fP execution, the use of any JIT optimization that might
! 581: have been set up by the \fB/S+\fP qualifier of \fB-s+\fP option is disabled.
1.1 misho 582: .P
583: The \fImatch_limit\fP number is a measure of the amount of backtracking
584: that takes place, and checking it out can be instructive. For most simple
585: matches, the number is quite small, but for patterns with very large numbers of
586: matching possibilities, it can become large very quickly with increasing length
587: of subject string. The \fImatch_limit_recursion\fP number is a measure of how
588: much stack (or, if PCRE is compiled with NO_RECURSE, how much heap) memory is
589: needed to complete the match attempt.
590: .P
591: When \eO is used, the value specified may be higher or lower than the size set
592: by the \fB-O\fP command line option (or defaulted to 45); \eO applies only to
1.1.1.2 ! misho 593: the call of \fBpcre[16]_exec()\fP for the line in which it appears.
1.1 misho 594: .P
595: If the \fB/P\fP modifier was present on the pattern, causing the POSIX wrapper
596: API to be used, the only option-setting sequences that have any effect are \eB,
597: \eN, and \eZ, causing REG_NOTBOL, REG_NOTEMPTY, and REG_NOTEOL, respectively,
598: to be passed to \fBregexec()\fP.
599: .
600: .
601: .SH "THE ALTERNATIVE MATCHING FUNCTION"
602: .rs
603: .sp
604: By default, \fBpcretest\fP uses the standard PCRE matching function,
1.1.1.2 ! misho 605: \fBpcre[16]_exec()\fP to match each data line. PCRE also supports an
! 606: alternative matching function, \fBpcre[16]_dfa_test()\fP, which operates in a
1.1 misho 607: different way, and has some restrictions. The differences between the two
608: functions are described in the
609: .\" HREF
610: \fBpcrematching\fP
611: .\"
612: documentation.
613: .P
614: If a data line contains the \eD escape sequence, or if the command line
1.1.1.2 ! misho 615: contains the \fB-dfa\fP option, the alternative matching function is used.
1.1 misho 616: This function finds all possible matches at a given point. If, however, the \eF
617: escape sequence is present in the data line, it stops after the first match is
618: found. This is always the shortest possible match.
619: .
620: .
621: .SH "DEFAULT OUTPUT FROM PCRETEST"
622: .rs
623: .sp
624: This section describes the output when the normal matching function,
1.1.1.2 ! misho 625: \fBpcre[16]_exec()\fP, is being used.
1.1 misho 626: .P
627: When a match succeeds, \fBpcretest\fP outputs the list of captured substrings
1.1.1.2 ! misho 628: that \fBpcre[16]_exec()\fP returns, starting with number 0 for the string that
1.1 misho 629: matched the whole pattern. Otherwise, it outputs "No match" when the return is
630: PCRE_ERROR_NOMATCH, and "Partial match:" followed by the partially matching
1.1.1.2 ! misho 631: substring when \fBpcre[16]_exec()\fP returns PCRE_ERROR_PARTIAL. (Note that
! 632: this is the entire substring that was inspected during the partial match; it
! 633: may include characters before the actual match start if a lookbehind assertion,
1.1 misho 634: \eK, \eb, or \eB was involved.) For any other return, \fBpcretest\fP outputs
635: the PCRE negative error number and a short descriptive phrase. If the error is
1.1.1.2 ! misho 636: a failed UTF string check, the offset of the start of the failing character and
! 637: the reason code are also output, provided that the size of the output vector is
! 638: at least two. Here is an example of an interactive \fBpcretest\fP run.
1.1 misho 639: .sp
640: $ pcretest
641: PCRE version 8.13 2011-04-30
642: .sp
643: re> /^abc(\ed+)/
644: data> abc123
645: 0: abc123
646: 1: 123
647: data> xyz
648: No match
649: .sp
650: Unset capturing substrings that are not followed by one that is set are not
1.1.1.2 ! misho 651: returned by \fBpcre[16]_exec()\fP, and are not shown by \fBpcretest\fP. In the
1.1 misho 652: following example, there are two capturing substrings, but when the first data
653: line is matched, the second, unset substring is not shown. An "internal" unset
654: substring is shown as "<unset>", as for the second data line.
655: .sp
656: re> /(a)|(b)/
657: data> a
658: 0: a
659: 1: a
660: data> b
661: 0: b
662: 1: <unset>
663: 2: b
664: .sp
1.1.1.2 ! misho 665: If the strings contain any non-printing characters, they are output as \exhh
! 666: escapes if the value is less than 256 and UTF mode is not set. Otherwise they
! 667: are output as \ex{hh...} escapes. See below for the definition of non-printing
! 668: characters. If the pattern has the \fB/+\fP modifier, the output for substring
! 669: 0 is followed by the the rest of the subject string, identified by "0+" like
! 670: this:
1.1 misho 671: .sp
672: re> /cat/+
673: data> cataract
674: 0: cat
675: 0+ aract
676: .sp
677: If the pattern has the \fB/g\fP or \fB/G\fP modifier, the results of successive
678: matching attempts are output in sequence, like this:
679: .sp
680: re> /\eBi(\ew\ew)/g
681: data> Mississippi
682: 0: iss
683: 1: ss
684: 0: iss
685: 1: ss
686: 0: ipp
687: 1: pp
688: .sp
689: "No match" is output only if the first match attempt fails. Here is an example
690: of a failure message (the offset 4 that is specified by \e>4 is past the end of
691: the subject string):
692: .sp
693: re> /xyz/
694: data> xyz\e>4
695: Error -24 (bad offset value)
696: .P
697: If any of the sequences \fB\eC\fP, \fB\eG\fP, or \fB\eL\fP are present in a
698: data line that is successfully matched, the substrings extracted by the
699: convenience functions are output with C, G, or L after the string number
700: instead of a colon. This is in addition to the normal full list. The string
701: length (that is, the return from the extraction function) is given in
702: parentheses after each string for \fB\eC\fP and \fB\eG\fP.
703: .P
704: Note that whereas patterns can be continued over several lines (a plain ">"
705: prompt is used for continuations), data lines may not. However newlines can be
706: included in data by means of the \en escape (or \er, \er\en, etc., depending on
707: the newline sequence setting).
708: .
709: .
710: .
711: .SH "OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION"
712: .rs
713: .sp
1.1.1.2 ! misho 714: When the alternative matching function, \fBpcre[16]_dfa_exec()\fP, is used (by
1.1 misho 715: means of the \eD escape sequence or the \fB-dfa\fP command line option), the
716: output consists of a list of all the matches that start at the first point in
717: the subject where there is at least one match. For example:
718: .sp
719: re> /(tang|tangerine|tan)/
720: data> yellow tangerine\eD
721: 0: tangerine
722: 1: tang
723: 2: tan
724: .sp
725: (Using the normal matching function on this data finds only "tang".) The
726: longest matching string is always given first (and numbered zero). After a
727: PCRE_ERROR_PARTIAL return, the output is "Partial match:", followed by the
728: partially matching substring. (Note that this is the entire substring that was
729: inspected during the partial match; it may include characters before the actual
730: match start if a lookbehind assertion, \eK, \eb, or \eB was involved.)
731: .P
732: If \fB/g\fP is present on the pattern, the search for further matches resumes
733: at the end of the longest match. For example:
734: .sp
735: re> /(tang|tangerine|tan)/g
736: data> yellow tangerine and tangy sultana\eD
737: 0: tangerine
738: 1: tang
739: 2: tan
740: 0: tang
741: 1: tan
742: 0: tan
743: .sp
744: Since the matching function does not support substring capture, the escape
745: sequences that are concerned with captured substrings are not relevant.
746: .
747: .
748: .SH "RESTARTING AFTER A PARTIAL MATCH"
749: .rs
750: .sp
751: When the alternative matching function has given the PCRE_ERROR_PARTIAL return,
752: indicating that the subject partially matched the pattern, you can restart the
753: match with additional subject data by means of the \eR escape sequence. For
754: example:
755: .sp
756: re> /^\ed?\ed(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\ed\ed$/
757: data> 23ja\eP\eD
758: Partial match: 23ja
759: data> n05\eR\eD
760: 0: n05
761: .sp
762: For further information about partial matching, see the
763: .\" HREF
764: \fBpcrepartial\fP
765: .\"
766: documentation.
767: .
768: .
769: .SH CALLOUTS
770: .rs
771: .sp
772: If the pattern contains any callout requests, \fBpcretest\fP's callout function
773: is called during matching. This works with both matching functions. By default,
774: the called function displays the callout number, the start and current
775: positions in the text at the callout time, and the next pattern item to be
1.1.1.2 ! misho 776: tested. For example:
1.1 misho 777: .sp
778: --->pqrabcdef
779: 0 ^ ^ \ed
780: .sp
1.1.1.2 ! misho 781: This output indicates that callout number 0 occurred for a match attempt
! 782: starting at the fourth character of the subject string, when the pointer was at
! 783: the seventh character of the data, and when the next pattern item was \ed. Just
! 784: one circumflex is output if the start and current positions are the same.
1.1 misho 785: .P
786: Callouts numbered 255 are assumed to be automatic callouts, inserted as a
787: result of the \fB/C\fP pattern modifier. In this case, instead of showing the
788: callout number, the offset in the pattern, preceded by a plus, is output. For
789: example:
790: .sp
791: re> /\ed?[A-E]\e*/C
792: data> E*
793: --->E*
794: +0 ^ \ed?
795: +3 ^ [A-E]
796: +8 ^^ \e*
797: +10 ^ ^
798: 0: E*
799: .sp
800: If a pattern contains (*MARK) items, an additional line is output whenever
801: a change of latest mark is passed to the callout function. For example:
802: .sp
803: re> /a(*MARK:X)bc/C
804: data> abc
805: --->abc
806: +0 ^ a
807: +1 ^^ (*MARK:X)
808: +10 ^^ b
809: Latest Mark: X
810: +11 ^ ^ c
811: +12 ^ ^
812: 0: abc
813: .sp
814: The mark changes between matching "a" and "b", but stays the same for the rest
815: of the match, so nothing more is output. If, as a result of backtracking, the
816: mark reverts to being unset, the text "<unset>" is output.
817: .P
818: The callout function in \fBpcretest\fP returns zero (carry on matching) by
819: default, but you can use a \eC item in a data line (as described above) to
820: change this and other parameters of the callout.
821: .P
822: Inserting callouts can be helpful when using \fBpcretest\fP to check
823: complicated regular expressions. For further information about callouts, see
824: the
825: .\" HREF
826: \fBpcrecallout\fP
827: .\"
828: documentation.
829: .
830: .
831: .
832: .SH "NON-PRINTING CHARACTERS"
833: .rs
834: .sp
835: When \fBpcretest\fP is outputting text in the compiled version of a pattern,
836: bytes other than 32-126 are always treated as non-printing characters are are
837: therefore shown as hex escapes.
838: .P
839: When \fBpcretest\fP is outputting text that is a matched part of a subject
840: string, it behaves in the same way, unless a different locale has been set for
841: the pattern (using the \fB/L\fP modifier). In this case, the \fBisprint()\fP
842: function to distinguish printing and non-printing characters.
843: .
844: .
845: .
846: .SH "SAVING AND RELOADING COMPILED PATTERNS"
847: .rs
848: .sp
849: The facilities described in this section are not available when the POSIX
850: interface to PCRE is being used, that is, when the \fB/P\fP pattern modifier is
851: specified.
852: .P
853: When the POSIX interface is not in use, you can cause \fBpcretest\fP to write a
854: compiled pattern to a file, by following the modifiers with > and a file name.
855: For example:
856: .sp
857: /pattern/im >/some/file
858: .sp
859: See the
860: .\" HREF
861: \fBpcreprecompile\fP
862: .\"
863: documentation for a discussion about saving and re-using compiled patterns.
864: Note that if the pattern was successfully studied with JIT optimization, the
865: JIT data cannot be saved.
866: .P
867: The data that is written is binary. The first eight bytes are the length of the
868: compiled pattern data followed by the length of the optional study data, each
869: written as four bytes in big-endian order (most significant byte first). If
870: there is no study data (either the pattern was not studied, or studying did not
871: return any data), the second length is zero. The lengths are followed by an
872: exact copy of the compiled pattern. If there is additional study data, this
873: (excluding any JIT data) follows immediately after the compiled pattern. After
874: writing the file, \fBpcretest\fP expects to read a new pattern.
875: .P
876: A saved pattern can be reloaded into \fBpcretest\fP by specifying < and a file
877: name instead of a pattern. The name of the file must not contain a < character,
878: as otherwise \fBpcretest\fP will interpret the line as a pattern delimited by <
879: characters.
880: For example:
881: .sp
882: re> </some/file
883: Compiled pattern loaded from /some/file
884: No study data
885: .sp
886: If the pattern was previously studied with the JIT optimization, the JIT
887: information cannot be saved and restored, and so is lost. When the pattern has
888: been loaded, \fBpcretest\fP proceeds to read data lines in the usual way.
889: .P
890: You can copy a file written by \fBpcretest\fP to a different host and reload it
891: there, even if the new host has opposite endianness to the one on which the
892: pattern was compiled. For example, you can compile on an i86 machine and run on
1.1.1.2 ! misho 893: a SPARC machine. When a pattern is reloaded on a host with different
! 894: endianness, the confirmation message is changed to:
! 895: .sp
! 896: Compiled pattern (byte-inverted) loaded from /some/file
! 897: .sp
! 898: The test suite contains some saved pre-compiled patterns with different
! 899: endianness. These are reloaded using "<!" instead of just "<". This suppresses
! 900: the "(byte-inverted)" text so that the output is the same on all hosts. It also
! 901: forces debugging output once the pattern has been reloaded.
1.1 misho 902: .P
903: File names for saving and reloading can be absolute or relative, but note that
904: the shell facility of expanding a file name that starts with a tilde (~) is not
905: available.
906: .P
907: The ability to save and reload files in \fBpcretest\fP is intended for testing
908: and experimentation. It is not intended for production use because only a
909: single pattern can be written to a file. Furthermore, there is no facility for
910: supplying custom character tables for use with a reloaded pattern. If the
911: original pattern was compiled with custom tables, an attempt to match a subject
912: string using a reloaded pattern is likely to cause \fBpcretest\fP to crash.
913: Finally, if you attempt to load a file that is not in the correct format, the
914: result is undefined.
915: .
916: .
917: .SH "SEE ALSO"
918: .rs
919: .sp
1.1.1.2 ! misho 920: \fBpcre\fP(3), \fBpcre16\fP(3), \fBpcreapi\fP(3), \fBpcrecallout\fP(3),
! 921: \fBpcrejit\fP, \fBpcrematching\fP(3), \fBpcrepartial\fP(d),
! 922: \fBpcrepattern\fP(3), \fBpcreprecompile\fP(3).
1.1 misho 923: .
924: .
925: .SH AUTHOR
926: .rs
927: .sp
928: .nf
929: Philip Hazel
930: University Computing Service
931: Cambridge CB2 3QH, England.
932: .fi
933: .
934: .
935: .SH REVISION
936: .rs
937: .sp
938: .nf
1.1.1.2 ! misho 939: Last updated: 14 January 2012
! 940: Copyright (c) 1997-2012 University of Cambridge.
1.1 misho 941: .fi
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>
![[BACK]](/icons/cvsweb/back.gif){kind=icon}
Return to pcretest.1 CVS log ![[TXT]](/icons/cvsweb/text.gif){kind=icon}
![[DIR]](/icons/cvsweb/dir.gif){kind=icon}
Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / pcre / doc