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revision 73 by nigel, Sat Feb 24 21:40:30 2007 UTC revision 553 by ph10, Fri Oct 22 15:57:50 2010 UTC
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2  .SH NAME  .SH NAME
3  pcretest - a program for testing Perl-compatible regular expressions.  pcretest - a program for testing Perl-compatible regular expressions.
4  .SH SYNOPSIS  .SH SYNOPSIS
5  .B pcretest "[-d] [-i] [-m] [-o osize] [-p] [-t] [source] [destination]"  .rs
6    .sp
7  \fBpcretest\fR was written as a test program for the PCRE regular expression  .B pcretest "[options] [source] [destination]"
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  library itself, but it can also be used for experimenting with regular
11  expressions. This document describes the features of the test program; for  expressions. This document describes the features of the test program; for
12  details of the regular expressions themselves, see the  details of the regular expressions themselves, see the
13  .\" HREF  .\" HREF
14  \fBpcrepattern\fR  \fBpcrepattern\fP
15  .\"  .\"
16  documentation. For details of PCRE and its options, see the  documentation. For details of the PCRE library function calls and their
17    options, see the
18  .\" HREF  .\" HREF
19  \fBpcreapi\fR  \fBpcreapi\fP
20  .\"  .\"
21  documentation.  documentation.
22    .
23    .
24  .SH OPTIONS  .SH OPTIONS
25  .rs  .rs
 .sp  
26  .TP 10  .TP 10
27  \fB-C\fR  \fB-b\fP
28    Behave as if each regex has the \fB/B\fP (show bytecode) modifier; the internal
29    form is output after compilation.
30    .TP 10
31    \fB-C\fP
32  Output the version number of the PCRE library, and all available information  Output the version number of the PCRE library, and all available information
33  about the optional features that are included, and then exit.  about the optional features that are included, and then exit.
34  .TP 10  .TP 10
35  \fB-d\fR  \fB-d\fP
36  Behave as if each regex had the \fB/D\fR modifier (see below); the internal  Behave as if each regex has the \fB/D\fP (debug) modifier; the internal
37  form is output after compilation.  form and information about the compiled pattern is output after compilation;
38    \fB-d\fP is equivalent to \fB-b -i\fP.
39  .TP 10  .TP 10
40  \fB-i\fR  \fB-dfa\fP
41  Behave as if each regex had the \fB/I\fR modifier; information about the  Behave as if each data line contains the \eD escape sequence; this causes the
42    alternative matching function, \fBpcre_dfa_exec()\fP, to be used instead of the
43    standard \fBpcre_exec()\fP function (more detail is given below).
44    .TP 10
45    \fB-help\fP
46    Output a brief summary these options and then exit.
47    .TP 10
48    \fB-i\fP
49    Behave as if each regex has the \fB/I\fP modifier; information about the
50  compiled pattern is given after compilation.  compiled pattern is given after compilation.
51  .TP 10  .TP 10
52  \fB-m\fR  \fB-M\fP
53    Behave as if each data line contains the \eM escape sequence; this causes
54    PCRE to discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings by
55    calling \fBpcre_exec()\fP repeatedly with different limits.
56    .TP 10
57    \fB-m\fP
58  Output the size of each compiled pattern after it has been compiled. This is  Output the size of each compiled pattern after it has been compiled. This is
59  equivalent to adding /M to each regular expression. For compatibility with  equivalent to adding \fB/M\fP to each regular expression. For compatibility
60  earlier versions of pcretest, \fB-s\fR is a synonym for \fB-m\fR.  with earlier versions of pcretest, \fB-s\fP is a synonym for \fB-m\fP.
61    .TP 10
62    \fB-o\fP \fIosize\fP
63    Set the number of elements in the output vector that is used when calling
64    \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP to be \fIosize\fP. The default value
65    is 45, which is enough for 14 capturing subexpressions for \fBpcre_exec()\fP or
66    22 different matches for \fBpcre_dfa_exec()\fP. The vector size can be
67    changed for individual matching calls by including \eO in the data line (see
68    below).
69  .TP 10  .TP 10
70  \fB-o\fR \fIosize\fR  \fB-p\fP
71  Set the number of elements in the output vector that is used when calling PCRE  Behave as if each regex has the \fB/P\fP modifier; the POSIX wrapper API is
72  to be \fIosize\fR. The default value is 45, which is enough for 14 capturing  used to call PCRE. None of the other options has any effect when \fB-p\fP is
73  subexpressions. The vector size can be changed for individual matching calls by  set.
 including \\O in the data line (see below).  
 .TP 10  
 \fB-p\fR  
 Behave as if each regex has \fB/P\fR modifier; the POSIX wrapper API is used  
 to call PCRE. None of the other options has any effect when \fB-p\fR is set.  
74  .TP 10  .TP 10
75  \fB-t\fR  \fB-q\fP
76    Do not output the version number of \fBpcretest\fP at the start of execution.
77    .TP 10
78    \fB-S\fP \fIsize\fP
79    On Unix-like systems, set the size of the runtime stack to \fIsize\fP
80    megabytes.
81    .TP 10
82    \fB-t\fP
83  Run each compile, study, and match many times with a timer, and output  Run each compile, study, and match many times with a timer, and output
84  resulting time per compile or match (in milliseconds). Do not set \fB-t\fR with  resulting time per compile or match (in milliseconds). Do not set \fB-m\fP with
85  \fB-m\fR, because you will then get the size output 20000 times and the timing  \fB-t\fP, because you will then get the size output a zillion times, and the
86  will be distorted.  timing will be distorted. You can control the number of iterations that are
87    used for timing by following \fB-t\fP with a number (as a separate item on the
88    command line). For example, "-t 1000" would iterate 1000 times. The default is
89    to iterate 500000 times.
90    .TP 10
91    \fB-tm\fP
92    This is like \fB-t\fP except that it times only the matching phase, not the
93    compile or study phases.
94    .
95    .
96  .SH DESCRIPTION  .SH DESCRIPTION
97  .rs  .rs
98  .sp  .sp
99  If \fBpcretest\fR is given two filename arguments, it reads from the first and  If \fBpcretest\fP is given two filename arguments, it reads from the first and
100  writes to the second. If it is given only one filename argument, it reads from  writes to the second. If it is given only one filename argument, it reads from
101  that file and writes to stdout. Otherwise, it reads from stdin and writes to  that file and writes to stdout. Otherwise, it reads from stdin and writes to
102  stdout, and prompts for each line of input, using "re>" to prompt for regular  stdout, and prompts for each line of input, using "re>" to prompt for regular
103  expressions, and "data>" to prompt for data lines.  expressions, and "data>" to prompt for data lines.
104    .P
105    When \fBpcretest\fP is built, a configuration option can specify that it should
106    be linked with the \fBlibreadline\fP library. When this is done, if the input
107    is from a terminal, it is read using the \fBreadline()\fP function. This
108    provides line-editing and history facilities. The output from the \fB-help\fP
109    option states whether or not \fBreadline()\fP will be used.
110    .P
111  The program handles any number of sets of input on a single input file. Each  The program handles any number of sets of input on a single input file. Each
112  set starts with a regular expression, and continues with any number of data  set starts with a regular expression, and continues with any number of data
113  lines to be matched against the pattern.  lines to be matched against the pattern.
114    .P
115  Each line is matched separately and independently. If you want to do  Each data line is matched separately and independently. If you want to do
116  multiple-line matches, you have to use the \\n escape sequence in a single line  multi-line matches, you have to use the \en escape sequence (or \er or \er\en,
117  of input to encode the newline characters. The maximum length of data line is  etc., depending on the newline setting) in a single line of input to encode the
118  30,000 characters.  newline sequences. There is no limit on the length of data lines; the input
119    buffer is automatically extended if it is too small.
120    .P
121  An empty line signals the end of the data lines, at which point a new regular  An empty line signals the end of the data lines, at which point a new regular
122  expression is read. The regular expressions are given enclosed in any  expression is read. The regular expressions are given enclosed in any
123  non-alphameric delimiters other than backslash, for example  non-alphanumeric delimiters other than backslash, for example:
124    .sp
125    /(a|bc)x+yz/    /(a|bc)x+yz/
126    .sp
127  White space before the initial delimiter is ignored. A regular expression may  White space before the initial delimiter is ignored. A regular expression may
128  be continued over several input lines, in which case the newline characters are  be continued over several input lines, in which case the newline characters are
129  included within it. It is possible to include the delimiter within the pattern  included within it. It is possible to include the delimiter within the pattern
130  by escaping it, for example  by escaping it, for example
131    .sp
132    /abc\\/def/    /abc\e/def/
133    .sp
134  If you do so, the escape and the delimiter form part of the pattern, but since  If you do so, the escape and the delimiter form part of the pattern, but since
135  delimiters are always non-alphameric, this does not affect its interpretation.  delimiters are always non-alphanumeric, this does not affect its interpretation.
136  If the terminating delimiter is immediately followed by a backslash, for  If the terminating delimiter is immediately followed by a backslash, for
137  example,  example,
138    .sp
139    /abc/\\    /abc/\e
140    .sp
141  then a backslash is added to the end of the pattern. This is done to provide a  then a backslash is added to the end of the pattern. This is done to provide a
142  way of testing the error condition that arises if a pattern finishes with a  way of testing the error condition that arises if a pattern finishes with a
143  backslash, because  backslash, because
144    .sp
145    /abc\\/    /abc\e/
146    .sp
147  is interpreted as the first line of a pattern that starts with "abc/", causing  is interpreted as the first line of a pattern that starts with "abc/", causing
148  pcretest to read the next line as a continuation of the regular expression.  pcretest to read the next line as a continuation of the regular expression.
149    .
150  .SH PATTERN MODIFIERS  .
151    .SH "PATTERN MODIFIERS"
152  .rs  .rs
153  .sp  .sp
154  The pattern may be followed by \fBi\fR, \fBm\fR, \fBs\fR, or \fBx\fR to set the  A pattern may be followed by any number of modifiers, which are mostly single
155  PCRE_CASELESS, PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options,  characters. Following Perl usage, these are referred to below as, for example,
156  respectively. For example:  "the \fB/i\fP modifier", even though the delimiter of the pattern need not
157    always be a slash, and no slash is used when writing modifiers. Whitespace may
158    appear between the final pattern delimiter and the first modifier, and between
159    the modifiers themselves.
160    .P
161    The \fB/i\fP, \fB/m\fP, \fB/s\fP, and \fB/x\fP modifiers set the PCRE_CASELESS,
162    PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when
163    \fBpcre_compile()\fP is called. These four modifier letters have the same
164    effect as they do in Perl. For example:
165    .sp
166    /caseless/i    /caseless/i
167    .sp
168  These modifier letters have the same effect as they do in Perl. There are  The following table shows additional modifiers for setting PCRE compile-time
169  others that set PCRE options that do not correspond to anything in Perl:  options that do not correspond to anything in Perl:
170  \fB/A\fR, \fB/E\fR, \fB/N\fR, \fB/U\fR, and \fB/X\fR set PCRE_ANCHORED,  .sp
171  PCRE_DOLLAR_ENDONLY, PCRE_NO_AUTO_CAPTURE, PCRE_UNGREEDY, and PCRE_EXTRA    \fB/8\fP              PCRE_UTF8
172  respectively.    \fB/?\fP              PCRE_NO_UTF8_CHECK
173      \fB/A\fP              PCRE_ANCHORED
174      \fB/C\fP              PCRE_AUTO_CALLOUT
175      \fB/E\fP              PCRE_DOLLAR_ENDONLY
176      \fB/f\fP              PCRE_FIRSTLINE
177      \fB/J\fP              PCRE_DUPNAMES
178      \fB/N\fP              PCRE_NO_AUTO_CAPTURE
179      \fB/U\fP              PCRE_UNGREEDY
180      \fB/W\fP              PCRE_UCP
181      \fB/X\fP              PCRE_EXTRA
182      \fB/<JS>\fP           PCRE_JAVASCRIPT_COMPAT
183      \fB/<cr>\fP           PCRE_NEWLINE_CR
184      \fB/<lf>\fP           PCRE_NEWLINE_LF
185      \fB/<crlf>\fP         PCRE_NEWLINE_CRLF
186      \fB/<anycrlf>\fP      PCRE_NEWLINE_ANYCRLF
187      \fB/<any>\fP          PCRE_NEWLINE_ANY
188      \fB/<bsr_anycrlf>\fP  PCRE_BSR_ANYCRLF
189      \fB/<bsr_unicode>\fP  PCRE_BSR_UNICODE
190    .sp
191    The modifiers that are enclosed in angle brackets are literal strings as shown,
192    including the angle brackets, but the letters can be in either case. This
193    example sets multiline matching with CRLF as the line ending sequence:
194    .sp
195      /^abc/m<crlf>
196    .sp
197    As well as turning on the PCRE_UTF8 option, the \fB/8\fP modifier also causes
198    any non-printing characters in output strings to be printed using the
199    \ex{hh...} notation if they are valid UTF-8 sequences. Full details of the PCRE
200    options are given in the
201    .\" HREF
202    \fBpcreapi\fP
203    .\"
204    documentation.
205    .
206    .
207    .SS "Finding all matches in a string"
208    .rs
209    .sp
210  Searching for all possible matches within each subject string can be requested  Searching for all possible matches within each subject string can be requested
211  by the \fB/g\fR or \fB/G\fR modifier. After finding a match, PCRE is called  by the \fB/g\fP or \fB/G\fP modifier. After finding a match, PCRE is called
212  again to search the remainder of the subject string. The difference between  again to search the remainder of the subject string. The difference between
213  \fB/g\fR and \fB/G\fR is that the former uses the \fIstartoffset\fR argument to  \fB/g\fP and \fB/G\fP is that the former uses the \fIstartoffset\fP argument to
214  \fBpcre_exec()\fR to start searching at a new point within the entire string  \fBpcre_exec()\fP to start searching at a new point within the entire string
215  (which is in effect what Perl does), whereas the latter passes over a shortened  (which is in effect what Perl does), whereas the latter passes over a shortened
216  substring. This makes a difference to the matching process if the pattern  substring. This makes a difference to the matching process if the pattern
217  begins with a lookbehind assertion (including \\b or \\B).  begins with a lookbehind assertion (including \eb or \eB).
218    .P
219  If any call to \fBpcre_exec()\fR in a \fB/g\fR or \fB/G\fR sequence matches an  If any call to \fBpcre_exec()\fP in a \fB/g\fP or \fB/G\fP sequence matches an
220  empty string, the next call is done with the PCRE_NOTEMPTY and PCRE_ANCHORED  empty string, the next call is done with the PCRE_NOTEMPTY_ATSTART and
221  flags set in order to search for another, non-empty, match at the same point.  PCRE_ANCHORED flags set in order to search for another, non-empty, match at the
222  If this second match fails, the start offset is advanced by one, and the normal  same point. If this second match fails, the start offset is advanced by one
223  match is retried. This imitates the way Perl handles such cases when using the  character, and the normal match is retried. This imitates the way Perl handles
224  \fB/g\fR modifier or the \fBsplit()\fR function.  such cases when using the \fB/g\fP modifier or the \fBsplit()\fP function.
225    .
226  There are a number of other modifiers for controlling the way \fBpcretest\fR  .
227    .SS "Other modifiers"
228    .rs
229    .sp
230    There are yet more modifiers for controlling the way \fBpcretest\fP
231  operates.  operates.
232    .P
233  The \fB/+\fR modifier requests that as well as outputting the substring that  The \fB/+\fP modifier requests that as well as outputting the substring that
234  matched the entire pattern, pcretest should in addition output the remainder of  matched the entire pattern, pcretest should in addition output the remainder of
235  the subject string. This is useful for tests where the subject contains  the subject string. This is useful for tests where the subject contains
236  multiple copies of the same substring.  multiple copies of the same substring.
237    .P
238  The \fB/L\fR modifier must be followed directly by the name of a locale, for  The \fB/B\fP modifier is a debugging feature. It requests that \fBpcretest\fP
239    output a representation of the compiled byte code after compilation. Normally
240    this information contains length and offset values; however, if \fB/Z\fP is
241    also present, this data is replaced by spaces. This is a special feature for
242    use in the automatic test scripts; it ensures that the same output is generated
243    for different internal link sizes.
244    .P
245    The \fB/D\fP modifier is a PCRE debugging feature, and is equivalent to
246    \fB/BI\fP, that is, both the \fB/B\fP and the \fB/I\fP modifiers.
247    .P
248    The \fB/F\fP modifier causes \fBpcretest\fP to flip the byte order of the
249    fields in the compiled pattern that contain 2-byte and 4-byte numbers. This
250    facility is for testing the feature in PCRE that allows it to execute patterns
251    that were compiled on a host with a different endianness. This feature is not
252    available when the POSIX interface to PCRE is being used, that is, when the
253    \fB/P\fP pattern modifier is specified. See also the section about saving and
254    reloading compiled patterns below.
255    .P
256    The \fB/I\fP modifier requests that \fBpcretest\fP output information about the
257    compiled pattern (whether it is anchored, has a fixed first character, and
258    so on). It does this by calling \fBpcre_fullinfo()\fP after compiling a
259    pattern. If the pattern is studied, the results of that are also output.
260    .P
261    The \fB/K\fP modifier requests \fBpcretest\fP to show names from backtracking
262    control verbs that are returned from calls to \fBpcre_exec()\fP. It causes
263    \fBpcretest\fP to create a \fBpcre_extra\fP block if one has not already been
264    created by a call to \fBpcre_study()\fP, and to set the PCRE_EXTRA_MARK flag
265    and the \fBmark\fP field within it, every time that \fBpcre_exec()\fP is
266    called. If the variable that the \fBmark\fP field points to is non-NULL for a
267    match, non-match, or partial match, \fBpcretest\fP prints the string to which
268    it points. For a match, this is shown on a line by itself, tagged with "MK:".
269    For a non-match it is added to the message.
270    .P
271    The \fB/L\fP modifier must be followed directly by the name of a locale, for
272  example,  example,
273    .sp
274    /pattern/Lfr    /pattern/Lfr_FR
275    .sp
276  For this reason, it must be the last modifier letter. The given locale is set,  For this reason, it must be the last modifier. The given locale is set,
277  \fBpcre_maketables()\fR is called to build a set of character tables for the  \fBpcre_maketables()\fP is called to build a set of character tables for the
278  locale, and this is then passed to \fBpcre_compile()\fR when compiling the  locale, and this is then passed to \fBpcre_compile()\fP when compiling the
279  regular expression. Without an \fB/L\fR modifier, NULL is passed as the tables  regular expression. Without an \fB/L\fP (or \fB/T\fP) modifier, NULL is passed
280  pointer; that is, \fB/L\fR applies only to the expression on which it appears.  as the tables pointer; that is, \fB/L\fP applies only to the expression on
281    which it appears.
282  The \fB/I\fR modifier requests that \fBpcretest\fR output information about the  .P
283  compiled expression (whether it is anchored, has a fixed first character, and  The \fB/M\fP modifier causes the size of memory block used to hold the compiled
284  so on). It does this by calling \fBpcre_fullinfo()\fR after compiling an  pattern to be output.
285  expression, and outputting the information it gets back. If the pattern is  .P
286  studied, the results of that are also output.  The \fB/S\fP modifier causes \fBpcre_study()\fP to be called after the
   
 The \fB/D\fR modifier is a PCRE debugging feature, which also assumes \fB/I\fR.  
 It causes the internal form of compiled regular expressions to be output after  
 compilation. If the pattern was studied, the information returned is also  
 output.  
   
 The \fB/S\fR modifier causes \fBpcre_study()\fR to be called after the  
287  expression has been compiled, and the results used when the expression is  expression has been compiled, and the results used when the expression is
288  matched.  matched.
289    .P
290  The \fB/M\fR modifier causes the size of memory block used to hold the compiled  The \fB/T\fP modifier must be followed by a single digit. It causes a specific
291  pattern to be output.  set of built-in character tables to be passed to \fBpcre_compile()\fP. It is
292    used in the standard PCRE tests to check behaviour with different character
293  The \fB/P\fR modifier causes \fBpcretest\fR to call PCRE via the POSIX wrapper  tables. The digit specifies the tables as follows:
294  API rather than its native API. When this is done, all other modifiers except  .sp
295  \fB/i\fR, \fB/m\fR, and \fB/+\fR are ignored. REG_ICASE is set if \fB/i\fR is    0   the default ASCII tables, as distributed in
296  present, and REG_NEWLINE is set if \fB/m\fR is present. The wrapper functions          pcre_chartables.c.dist
297  force PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless REG_NEWLINE is set.    1   a set of tables defining ISO 8859 characters
298    .sp
299  The \fB/8\fR modifier causes \fBpcretest\fR to call PCRE with the PCRE_UTF8  In table 1, some characters whose codes are greater than 128 are identified as
300  option set. This turns on support for UTF-8 character handling in PCRE,  letters, digits, spaces, etc.
301  provided that it was compiled with this support enabled. This modifier also  .
302  causes any non-printing characters in output strings to be printed using the  .
303  \\x{hh...} notation if they are valid UTF-8 sequences.  .SS "Using the POSIX wrapper API"
   
 If the \fB/?\fR modifier is used with \fB/8\fR, it causes \fBpcretest\fR to  
 call \fBpcre_compile()\fR with the PCRE_NO_UTF8_CHECK option, to suppress the  
 checking of the string for UTF-8 validity.  
   
 .SH CALLOUTS  
304  .rs  .rs
305  .sp  .sp
306  If the pattern contains any callout requests, \fBpcretest\fR's callout function  The \fB/P\fP modifier causes \fBpcretest\fP to call PCRE via the POSIX wrapper
307  will be called. By default, it displays the callout number, and the start and  API rather than its native API. When \fB/P\fP is set, the following modifiers
308  current positions in the text at the callout time. For example, the output  set options for the \fBregcomp()\fP function:
309    .sp
310    --->pqrabcdef    /i    REG_ICASE
311      0    ^  ^    /m    REG_NEWLINE
312      /N    REG_NOSUB
313  indicates that callout number 0 occurred for a match attempt starting at the    /s    REG_DOTALL     )
314  fourth character of the subject string, when the pointer was at the seventh    /U    REG_UNGREEDY   ) These options are not part of
315  character. The callout function returns zero (carry on matching) by default.    /W    REG_UCP        )   the POSIX standard
316      /8    REG_UTF8       )
317  Inserting callouts may be helpful when using \fBpcretest\fR to check  .sp
318  complicated regular expressions. For further information about callouts, see  The \fB/+\fP modifier works as described above. All other modifiers are
319  the  ignored.
320  .\" HREF  .
321  \fBpcrecallout\fR  .
322  .\"  .SH "DATA LINES"
 documentation.  
   
 For testing the PCRE library, additional control of callout behaviour is  
 available via escape sequences in the data, as described in the following  
 section. In particular, it is possible to pass in a number as callout data (the  
 default is zero). If the callout function receives a non-zero number, it  
 returns that value instead of zero.  
   
 .SH DATA LINES  
323  .rs  .rs
324  .sp  .sp
325  Before each data line is passed to \fBpcre_exec()\fR, leading and trailing  Before each data line is passed to \fBpcre_exec()\fP, leading and trailing
326  whitespace is removed, and it is then scanned for \\ escapes. Some of these are  whitespace is removed, and it is then scanned for \e escapes. Some of these are
327  pretty esoteric features, intended for checking out some of the more  pretty esoteric features, intended for checking out some of the more
328  complicated features of PCRE. If you are just testing "ordinary" regular  complicated features of PCRE. If you are just testing "ordinary" regular
329  expressions, you probably don't need any of these. The following escapes are  expressions, you probably don't need any of these. The following escapes are
330  recognized:  recognized:
331    .sp
332    \\a         alarm (= BEL)    \ea         alarm (BEL, \ex07)
333    \\b         backspace    \eb         backspace (\ex08)
334    \\e         escape    \ee         escape (\ex27)
335    \\f         formfeed    \ef         formfeed (\ex0c)
336    \\n         newline    \en         newline (\ex0a)
337    \\r         carriage return  .\" JOIN
338    \\t         tab    \eqdd       set the PCRE_MATCH_LIMIT limit to dd
339    \\v         vertical tab                 (any number of digits)
340    \\nnn       octal character (up to 3 octal digits)    \er         carriage return (\ex0d)
341    \\xhh       hexadecimal character (up to 2 hex digits)    \et         tab (\ex09)
342    \\x{hh...}  hexadecimal character, any number of digits    \ev         vertical tab (\ex0b)
343      \ennn       octal character (up to 3 octal digits)
344      \exhh       hexadecimal character (up to 2 hex digits)
345    .\" JOIN
346      \ex{hh...}  hexadecimal character, any number of digits
347                 in UTF-8 mode                 in UTF-8 mode
348    \\A         pass the PCRE_ANCHORED option to \fBpcre_exec()\fR  .\" JOIN
349    \\B         pass the PCRE_NOTBOL option to \fBpcre_exec()\fR    \eA         pass the PCRE_ANCHORED option to \fBpcre_exec()\fP
350    \\Cdd       call pcre_copy_substring() for substring dd                 or \fBpcre_dfa_exec()\fP
351                 after a successful match (any decimal number  .\" JOIN
352                 less than 32)    \eB         pass the PCRE_NOTBOL option to \fBpcre_exec()\fP
353    \\Cname     call pcre_copy_named_substring() for substring                 or \fBpcre_dfa_exec()\fP
354    .\" JOIN
355      \eCdd       call pcre_copy_substring() for substring dd
356                   after a successful match (number less than 32)
357    .\" JOIN
358      \eCname     call pcre_copy_named_substring() for substring
359                 "name" after a successful match (name termin-                 "name" after a successful match (name termin-
360                 ated by next non alphanumeric character)                 ated by next non alphanumeric character)
361    \\C+        show the current captured substrings at callout  .\" JOIN
362      \eC+        show the current captured substrings at callout
363                 time                 time
364    \\C-        do not supply a callout function    \eC-        do not supply a callout function
365    \\C!n       return 1 instead of 0 when callout number n is  .\" JOIN
366      \eC!n       return 1 instead of 0 when callout number n is
367                 reached                 reached
368    \\C!n!m     return 1 instead of 0 when callout number n is  .\" JOIN
369      \eC!n!m     return 1 instead of 0 when callout number n is
370                 reached for the nth time                 reached for the nth time
371    \\C*n       pass the number n (may be negative) as callout  .\" JOIN
372                 data    \eC*n       pass the number n (may be negative) as callout
373    \\Gdd       call pcre_get_substring() for substring dd                 data; this is used as the callout return value
374                 after a successful match (any decimal number    \eD         use the \fBpcre_dfa_exec()\fP match function
375                 less than 32)    \eF         only shortest match for \fBpcre_dfa_exec()\fP
376    \\Gname     call pcre_get_named_substring() for substring  .\" JOIN
377      \eGdd       call pcre_get_substring() for substring dd
378                   after a successful match (number less than 32)
379    .\" JOIN
380      \eGname     call pcre_get_named_substring() for substring
381                 "name" after a successful match (name termin-                 "name" after a successful match (name termin-
382                 ated by next non-alphanumeric character)                 ated by next non-alphanumeric character)
383    \\L         call pcre_get_substringlist() after a  .\" JOIN
384      \eL         call pcre_get_substringlist() after a
385                 successful match                 successful match
386    \\M         discover the minimum MATCH_LIMIT setting  .\" JOIN
387    \\N         pass the PCRE_NOTEMPTY option to \fBpcre_exec()\fR    \eM         discover the minimum MATCH_LIMIT and
388    \\Odd       set the size of the output vector passed to                 MATCH_LIMIT_RECURSION settings
389                 \fBpcre_exec()\fR to dd (any number of decimal  .\" JOIN
390                 digits)    \eN         pass the PCRE_NOTEMPTY option to \fBpcre_exec()\fP
391    \\S         output details of memory get/free calls during matching                 or \fBpcre_dfa_exec()\fP; if used twice, pass the
392    \\Z         pass the PCRE_NOTEOL option to \fBpcre_exec()\fR                 PCRE_NOTEMPTY_ATSTART option
393    \\?         pass the PCRE_NO_UTF8_CHECK option to  .\" JOIN
394                 \fBpcre_exec()\fR    \eOdd       set the size of the output vector passed to
395                   \fBpcre_exec()\fP to dd (any number of digits)
396  If \\M is present, \fBpcretest\fR calls \fBpcre_exec()\fR several times, with  .\" JOIN
397  different values in the \fImatch_limit\fR field of the \fBpcre_extra\fR data    \eP         pass the PCRE_PARTIAL_SOFT option to \fBpcre_exec()\fP
398  structure, until it finds the minimum number that is needed for                 or \fBpcre_dfa_exec()\fP; if used twice, pass the
399  \fBpcre_exec()\fR to complete. This number is a measure of the amount of                 PCRE_PARTIAL_HARD option
400  recursion and backtracking that takes place, and checking it out can be  .\" JOIN
401  instructive. For most simple matches, the number is quite small, but for    \eQdd       set the PCRE_MATCH_LIMIT_RECURSION limit to dd
402  patterns with very large numbers of matching possibilities, it can become large                 (any number of digits)
403  very quickly with increasing length of subject string.    \eR         pass the PCRE_DFA_RESTART option to \fBpcre_dfa_exec()\fP
404      \eS         output details of memory get/free calls during matching
405  When \\O is used, it may be higher or lower than the size set by the \fB-O\fR  .\" JOIN
406  option (or defaulted to 45); \\O applies only to the call of \fBpcre_exec()\fR    \eY         pass the PCRE_NO_START_OPTIMIZE option to \fBpcre_exec()\fP
407  for the line in which it appears.                 or \fBpcre_dfa_exec()\fP
408    .\" JOIN
409  A backslash followed by anything else just escapes the anything else. If the    \eZ         pass the PCRE_NOTEOL option to \fBpcre_exec()\fP
410  very last character is a backslash, it is ignored. This gives a way of passing                 or \fBpcre_dfa_exec()\fP
411  an empty line as data, since a real empty line terminates the data input.  .\" JOIN
412      \e?         pass the PCRE_NO_UTF8_CHECK option to
413  If \fB/P\fR was present on the regex, causing the POSIX wrapper API to be used,                 \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP
414  only \fB\B\fR, and \fB\Z\fR have any effect, causing REG_NOTBOL and REG_NOTEOL    \e>dd       start the match at offset dd (any number of digits);
415  to be passed to \fBregexec()\fR respectively.  .\" JOIN
416                   this sets the \fIstartoffset\fP argument for \fBpcre_exec()\fP
417  The use of \\x{hh...} to represent UTF-8 characters is not dependent on the use                 or \fBpcre_dfa_exec()\fP
418  of the \fB/8\fR modifier on the pattern. It is recognized always. There may be  .\" JOIN
419      \e<cr>      pass the PCRE_NEWLINE_CR option to \fBpcre_exec()\fP
420                   or \fBpcre_dfa_exec()\fP
421    .\" JOIN
422      \e<lf>      pass the PCRE_NEWLINE_LF option to \fBpcre_exec()\fP
423                   or \fBpcre_dfa_exec()\fP
424    .\" JOIN
425      \e<crlf>    pass the PCRE_NEWLINE_CRLF option to \fBpcre_exec()\fP
426                   or \fBpcre_dfa_exec()\fP
427    .\" JOIN
428      \e<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to \fBpcre_exec()\fP
429                   or \fBpcre_dfa_exec()\fP
430    .\" JOIN
431      \e<any>     pass the PCRE_NEWLINE_ANY option to \fBpcre_exec()\fP
432                   or \fBpcre_dfa_exec()\fP
433    .sp
434    The escapes that specify line ending sequences are literal strings, exactly as
435    shown. No more than one newline setting should be present in any data line.
436    .P
437    A backslash followed by anything else just escapes the anything else. If
438    the very last character is a backslash, it is ignored. This gives a way of
439    passing an empty line as data, since a real empty line terminates the data
440    input.
441    .P
442    If \eM is present, \fBpcretest\fP calls \fBpcre_exec()\fP several times, with
443    different values in the \fImatch_limit\fP and \fImatch_limit_recursion\fP
444    fields of the \fBpcre_extra\fP data structure, until it finds the minimum
445    numbers for each parameter that allow \fBpcre_exec()\fP to complete. The
446    \fImatch_limit\fP number is a measure of the amount of backtracking that takes
447    place, and checking it out can be instructive. For most simple matches, the
448    number is quite small, but for patterns with very large numbers of matching
449    possibilities, it can become large very quickly with increasing length of
450    subject string. The \fImatch_limit_recursion\fP number is a measure of how much
451    stack (or, if PCRE is compiled with NO_RECURSE, how much heap) memory is needed
452    to complete the match attempt.
453    .P
454    When \eO is used, the value specified may be higher or lower than the size set
455    by the \fB-O\fP command line option (or defaulted to 45); \eO applies only to
456    the call of \fBpcre_exec()\fP for the line in which it appears.
457    .P
458    If the \fB/P\fP modifier was present on the pattern, causing the POSIX wrapper
459    API to be used, the only option-setting sequences that have any effect are \eB,
460    \eN, and \eZ, causing REG_NOTBOL, REG_NOTEMPTY, and REG_NOTEOL, respectively,
461    to be passed to \fBregexec()\fP.
462    .P
463    The use of \ex{hh...} to represent UTF-8 characters is not dependent on the use
464    of the \fB/8\fP modifier on the pattern. It is recognized always. There may be
465  any number of hexadecimal digits inside the braces. The result is from one to  any number of hexadecimal digits inside the braces. The result is from one to
466  six bytes, encoded according to the UTF-8 rules.  six bytes, encoded according to the original UTF-8 rules of RFC 2279. This
467    allows for values in the range 0 to 0x7FFFFFFF. Note that not all of those are
468  .SH OUTPUT FROM PCRETEST  valid Unicode code points, or indeed valid UTF-8 characters according to the
469    later rules in RFC 3629.
470    .
471    .
472    .SH "THE ALTERNATIVE MATCHING FUNCTION"
473    .rs
474    .sp
475    By default, \fBpcretest\fP uses the standard PCRE matching function,
476    \fBpcre_exec()\fP to match each data line. From release 6.0, PCRE supports an
477    alternative matching function, \fBpcre_dfa_test()\fP, which operates in a
478    different way, and has some restrictions. The differences between the two
479    functions are described in the
480    .\" HREF
481    \fBpcrematching\fP
482    .\"
483    documentation.
484    .P
485    If a data line contains the \eD escape sequence, or if the command line
486    contains the \fB-dfa\fP option, the alternative matching function is called.
487    This function finds all possible matches at a given point. If, however, the \eF
488    escape sequence is present in the data line, it stops after the first match is
489    found. This is always the shortest possible match.
490    .
491    .
492    .SH "DEFAULT OUTPUT FROM PCRETEST"
493  .rs  .rs
494  .sp  .sp
495    This section describes the output when the normal matching function,
496    \fBpcre_exec()\fP, is being used.
497    .P
498  When a match succeeds, pcretest outputs the list of captured substrings that  When a match succeeds, pcretest outputs the list of captured substrings that
499  \fBpcre_exec()\fR returns, starting with number 0 for the string that matched  \fBpcre_exec()\fP returns, starting with number 0 for the string that matched
500  the whole pattern. Here is an example of an interactive pcretest run.  the whole pattern. Otherwise, it outputs "No match" when the return is
501    PCRE_ERROR_NOMATCH, and "Partial match:" followed by the partially matching
502    substring when \fBpcre_exec()\fP returns PCRE_ERROR_PARTIAL. (Note that this is
503    the entire substring that was inspected during the partial match; it may
504    include characters before the actual match start if a lookbehind assertion,
505    \eK, \eb, or \eB was involved.) For any other returns, it outputs the PCRE
506    negative error number. Here is an example of an interactive \fBpcretest\fP run.
507    .sp
508    $ pcretest    $ pcretest
509    PCRE version 4.00 08-Jan-2003    PCRE version 7.0 30-Nov-2006
510    .sp
511      re> /^abc(\\d+)/      re> /^abc(\ed+)/
512    data> abc123    data> abc123
513     0: abc123     0: abc123
514     1: 123     1: 123
515    data> xyz    data> xyz
516    No match    No match
517    .sp
518  If the strings contain any non-printing characters, they are output as \\0x  Note that unset capturing substrings that are not followed by one that is set
519  escapes, or as \\x{...} escapes if the \fB/8\fR modifier was present on the  are not returned by \fBpcre_exec()\fP, and are not shown by \fBpcretest\fP. In
520  pattern. If the pattern has the \fB/+\fR modifier, then the output for  the following example, there are two capturing substrings, but when the first
521  substring 0 is followed by the the rest of the subject string, identified by  data line is matched, the second, unset substring is not shown. An "internal"
522  "0+" like this:  unset substring is shown as "<unset>", as for the second data line.
523    .sp
524        re> /(a)|(b)/
525      data> a
526       0: a
527       1: a
528      data> b
529       0: b
530       1: <unset>
531       2: b
532    .sp
533    If the strings contain any non-printing characters, they are output as \e0x
534    escapes, or as \ex{...} escapes if the \fB/8\fP modifier was present on the
535    pattern. See below for the definition of non-printing characters. If the
536    pattern has the \fB/+\fP modifier, the output for substring 0 is followed by
537    the the rest of the subject string, identified by "0+" like this:
538    .sp
539      re> /cat/+      re> /cat/+
540    data> cataract    data> cataract
541     0: cat     0: cat
542     0+ aract     0+ aract
543    .sp
544  If the pattern has the \fB/g\fR or \fB/G\fR modifier, the results of successive  If the pattern has the \fB/g\fP or \fB/G\fP modifier, the results of successive
545  matching attempts are output in sequence, like this:  matching attempts are output in sequence, like this:
546    .sp
547      re> /\\Bi(\\w\\w)/g      re> /\eBi(\ew\ew)/g
548    data> Mississippi    data> Mississippi
549     0: iss     0: iss
550     1: ss     1: ss
# Line 335  matching attempts are output in sequence Line 552  matching attempts are output in sequence
552     1: ss     1: ss
553     0: ipp     0: ipp
554     1: pp     1: pp
555    .sp
556  "No match" is output only if the first match attempt fails.  "No match" is output only if the first match attempt fails.
557    .P
558  If any of the sequences \fB\\C\fR, \fB\\G\fR, or \fB\\L\fR are present in a  If any of the sequences \fB\eC\fP, \fB\eG\fP, or \fB\eL\fP are present in a
559  data line that is successfully matched, the substrings extracted by the  data line that is successfully matched, the substrings extracted by the
560  convenience functions are output with C, G, or L after the string number  convenience functions are output with C, G, or L after the string number
561  instead of a colon. This is in addition to the normal full list. The string  instead of a colon. This is in addition to the normal full list. The string
562  length (that is, the return from the extraction function) is given in  length (that is, the return from the extraction function) is given in
563  parentheses after each string for \fB\\C\fR and \fB\\G\fR.  parentheses after each string for \fB\eC\fP and \fB\eG\fP.
564    .P
565  Note that while patterns can be continued over several lines (a plain ">"  Note that whereas patterns can be continued over several lines (a plain ">"
566  prompt is used for continuations), data lines may not. However newlines can be  prompt is used for continuations), data lines may not. However newlines can be
567  included in data by means of the \\n escape.  included in data by means of the \en escape (or \er, \er\en, etc., depending on
568    the newline sequence setting).
569    .
570    .
571    .
572    .SH "OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION"
573    .rs
574    .sp
575    When the alternative matching function, \fBpcre_dfa_exec()\fP, is used (by
576    means of the \eD escape sequence or the \fB-dfa\fP command line option), the
577    output consists of a list of all the matches that start at the first point in
578    the subject where there is at least one match. For example:
579    .sp
580        re> /(tang|tangerine|tan)/
581      data> yellow tangerine\eD
582       0: tangerine
583       1: tang
584       2: tan
585    .sp
586    (Using the normal matching function on this data finds only "tang".) The
587    longest matching string is always given first (and numbered zero). After a
588    PCRE_ERROR_PARTIAL return, the output is "Partial match:", followed by the
589    partially matching substring. (Note that this is the entire substring that was
590    inspected during the partial match; it may include characters before the actual
591    match start if a lookbehind assertion, \eK, \eb, or \eB was involved.)
592    .P
593    If \fB/g\fP is present on the pattern, the search for further matches resumes
594    at the end of the longest match. For example:
595    .sp
596        re> /(tang|tangerine|tan)/g
597      data> yellow tangerine and tangy sultana\eD
598       0: tangerine
599       1: tang
600       2: tan
601       0: tang
602       1: tan
603       0: tan
604    .sp
605    Since the matching function does not support substring capture, the escape
606    sequences that are concerned with captured substrings are not relevant.
607    .
608    .
609    .SH "RESTARTING AFTER A PARTIAL MATCH"
610    .rs
611    .sp
612    When the alternative matching function has given the PCRE_ERROR_PARTIAL return,
613    indicating that the subject partially matched the pattern, you can restart the
614    match with additional subject data by means of the \eR escape sequence. For
615    example:
616    .sp
617        re> /^\ed?\ed(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\ed\ed$/
618      data> 23ja\eP\eD
619      Partial match: 23ja
620      data> n05\eR\eD
621       0: n05
622    .sp
623    For further information about partial matching, see the
624    .\" HREF
625    \fBpcrepartial\fP
626    .\"
627    documentation.
628    .
629    .
630    .SH CALLOUTS
631    .rs
632    .sp
633    If the pattern contains any callout requests, \fBpcretest\fP's callout function
634    is called during matching. This works with both matching functions. By default,
635    the called function displays the callout number, the start and current
636    positions in the text at the callout time, and the next pattern item to be
637    tested. For example, the output
638    .sp
639      --->pqrabcdef
640        0    ^  ^     \ed
641    .sp
642    indicates that callout number 0 occurred for a match attempt starting at the
643    fourth character of the subject string, when the pointer was at the seventh
644    character of the data, and when the next pattern item was \ed. Just one
645    circumflex is output if the start and current positions are the same.
646    .P
647    Callouts numbered 255 are assumed to be automatic callouts, inserted as a
648    result of the \fB/C\fP pattern modifier. In this case, instead of showing the
649    callout number, the offset in the pattern, preceded by a plus, is output. For
650    example:
651    .sp
652        re> /\ed?[A-E]\e*/C
653      data> E*
654      --->E*
655       +0 ^      \ed?
656       +3 ^      [A-E]
657       +8 ^^     \e*
658      +10 ^ ^
659       0: E*
660    .sp
661    The callout function in \fBpcretest\fP returns zero (carry on matching) by
662    default, but you can use a \eC item in a data line (as described above) to
663    change this.
664    .P
665    Inserting callouts can be helpful when using \fBpcretest\fP to check
666    complicated regular expressions. For further information about callouts, see
667    the
668    .\" HREF
669    \fBpcrecallout\fP
670    .\"
671    documentation.
672    .
673    .
674    .
675    .SH "NON-PRINTING CHARACTERS"
676    .rs
677    .sp
678    When \fBpcretest\fP is outputting text in the compiled version of a pattern,
679    bytes other than 32-126 are always treated as non-printing characters are are
680    therefore shown as hex escapes.
681    .P
682    When \fBpcretest\fP is outputting text that is a matched part of a subject
683    string, it behaves in the same way, unless a different locale has been set for
684    the pattern (using the \fB/L\fP modifier). In this case, the \fBisprint()\fP
685    function to distinguish printing and non-printing characters.
686    .
687    .
688    .
689    .SH "SAVING AND RELOADING COMPILED PATTERNS"
690    .rs
691    .sp
692    The facilities described in this section are not available when the POSIX
693    inteface to PCRE is being used, that is, when the \fB/P\fP pattern modifier is
694    specified.
695    .P
696    When the POSIX interface is not in use, you can cause \fBpcretest\fP to write a
697    compiled pattern to a file, by following the modifiers with > and a file name.
698    For example:
699    .sp
700      /pattern/im >/some/file
701    .sp
702    See the
703    .\" HREF
704    \fBpcreprecompile\fP
705    .\"
706    documentation for a discussion about saving and re-using compiled patterns.
707    .P
708    The data that is written is binary. The first eight bytes are the length of the
709    compiled pattern data followed by the length of the optional study data, each
710    written as four bytes in big-endian order (most significant byte first). If
711    there is no study data (either the pattern was not studied, or studying did not
712    return any data), the second length is zero. The lengths are followed by an
713    exact copy of the compiled pattern. If there is additional study data, this
714    follows immediately after the compiled pattern. After writing the file,
715    \fBpcretest\fP expects to read a new pattern.
716    .P
717    A saved pattern can be reloaded into \fBpcretest\fP by specifing < and a file
718    name instead of a pattern. The name of the file must not contain a < character,
719    as otherwise \fBpcretest\fP will interpret the line as a pattern delimited by <
720    characters.
721    For example:
722    .sp
723       re> </some/file
724      Compiled regex loaded from /some/file
725      No study data
726    .sp
727    When the pattern has been loaded, \fBpcretest\fP proceeds to read data lines in
728    the usual way.
729    .P
730    You can copy a file written by \fBpcretest\fP to a different host and reload it
731    there, even if the new host has opposite endianness to the one on which the
732    pattern was compiled. For example, you can compile on an i86 machine and run on
733    a SPARC machine.
734    .P
735    File names for saving and reloading can be absolute or relative, but note that
736    the shell facility of expanding a file name that starts with a tilde (~) is not
737    available.
738    .P
739    The ability to save and reload files in \fBpcretest\fP is intended for testing
740    and experimentation. It is not intended for production use because only a
741    single pattern can be written to a file. Furthermore, there is no facility for
742    supplying custom character tables for use with a reloaded pattern. If the
743    original pattern was compiled with custom tables, an attempt to match a subject
744    string using a reloaded pattern is likely to cause \fBpcretest\fP to crash.
745    Finally, if you attempt to load a file that is not in the correct format, the
746    result is undefined.
747    .
748    .
749    .SH "SEE ALSO"
750    .rs
751    .sp
752    \fBpcre\fP(3), \fBpcreapi\fP(3), \fBpcrecallout\fP(3), \fBpcrematching\fP(3),
753    \fBpcrepartial\fP(d), \fBpcrepattern\fP(3), \fBpcreprecompile\fP(3).
754    .
755    .
756  .SH AUTHOR  .SH AUTHOR
757  .rs  .rs
758  .sp  .sp
759  Philip Hazel <ph10@cam.ac.uk>  .nf
760  .br  Philip Hazel
761  University Computing Service,  University Computing Service
762  .br  Cambridge CB2 3QH, England.
763  Cambridge CB2 3QG, England.  .fi
764    .
765  .in 0  .
766  Last updated: 09 December 2003  .SH REVISION
767  .br  .rs
768  Copyright (c) 1997-2003 University of Cambridge.  .sp
769    .nf
770    Last updated: 22 October 2010
771    Copyright (c) 1997-2010 University of Cambridge.
772    .fi

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