PCRETEST(1) PCRETEST(1)
-
NAME
pcretest - a program for testing Perl-compatible regular expressions.
+
SYNOPSIS
- pcretest [-C] [-d] [-dfa] [-i] [-m] [-o osize] [-p] [-t] [source]
- [destination]
+ pcretest [options] [source] [destination]
pcretest was written as a test program for the PCRE regular expression
library itself, but it can also be used for experimenting with regular
OPTIONS
+ -b Behave as if each regex has the /B (show bytecode) modifier;
+ the internal form is output after compilation.
+
-C Output the version number of the PCRE library, and all avail-
- able information about the optional features that are
+ able information about the optional features that are
included, and then exit.
- -d Behave as if each regex has the /D (debug) modifier; the
- internal form is output after compilation.
+ -d Behave as if each regex has the /D (debug) modifier; the
+ internal form and information about the compiled pattern is
+ output after compilation; -d is equivalent to -b -i.
-dfa Behave as if each data line contains the \D escape sequence;
this causes the alternative matching function,
pcre_dfa_exec(), to be used instead of the standard
pcre_exec() function (more detail is given below).
+ -help Output a brief summary these options and then exit.
+
-i Behave as if each regex has the /I modifier; information
about the compiled pattern is given after compilation.
pcretest, -s is a synonym for -m.
-o osize Set the number of elements in the output vector that is used
- when calling pcre_exec() to be osize. The default value is
- 45, which is enough for 14 capturing subexpressions. The vec-
- tor size can be changed for individual matching calls by
- including \O in the data line (see below).
+ when calling pcre_exec() or pcre_dfa_exec() to be osize. The
+ default value is 45, which is enough for 14 capturing subex-
+ pressions for pcre_exec() or 22 different matches for
+ pcre_dfa_exec(). The vector size can be changed for individ-
+ ual matching calls by including \O in the data line (see
+ below).
-p Behave as if each regex has the /P modifier; the POSIX wrap-
per API is used to call PCRE. None of the other options has
any effect when -p is set.
+ -q Do not output the version number of pcretest at the start of
+ execution.
+
+ -S size On Unix-like systems, set the size of the runtime stack to
+ size megabytes.
+
-t Run each compile, study, and match many times with a timer,
and output resulting time per compile or match (in millisec-
onds). Do not set -m with -t, because you will then get the
size output a zillion times, and the timing will be dis-
- torted.
+ torted. You can control the number of iterations that are
+ used for timing by following -t with a number (as a separate
+ item on the command line). For example, "-t 1000" would iter-
+ ate 1000 times. The default is to iterate 500000 times.
+
+ -tm This is like -t except that it times only the matching phase,
+ not the compile or study phases.
DESCRIPTION
ber of data lines to be matched against the pattern.
Each data line is matched separately and independently. If you want to
- do multiple-line matches, you have to use the \n escape sequence in a
- single line of input to encode the newline characters. The maximum
- length of data line is 30,000 characters.
+ do multi-line matches, you have to use the \n escape sequence (or \r or
+ \r\n, etc., depending on the newline setting) in a single line of input
+ to encode the newline sequences. There is no limit on the length of
+ data lines; the input buffer is automatically extended if it is too
+ small.
An empty line signals the end of the data lines, at which point a new
regular expression is read. The regular expressions are given enclosed
- in any non-alphanumeric delimiters other than backslash, for example
+ in any non-alphanumeric delimiters other than backslash, for example:
/(a|bc)x+yz/
The following table shows additional modifiers for setting PCRE options
that do not correspond to anything in Perl:
- /A PCRE_ANCHORED
- /C PCRE_AUTO_CALLOUT
- /E PCRE_DOLLAR_ENDONLY
- /f PCRE_FIRSTLINE
- /N PCRE_NO_AUTO_CAPTURE
- /U PCRE_UNGREEDY
- /X PCRE_EXTRA
+ /A PCRE_ANCHORED
+ /C PCRE_AUTO_CALLOUT
+ /E PCRE_DOLLAR_ENDONLY
+ /f PCRE_FIRSTLINE
+ /J PCRE_DUPNAMES
+ /N PCRE_NO_AUTO_CAPTURE
+ /U PCRE_UNGREEDY
+ /X PCRE_EXTRA
+ /<cr> PCRE_NEWLINE_CR
+ /<lf> PCRE_NEWLINE_LF
+ /<crlf> PCRE_NEWLINE_CRLF
+ /<anycrlf> PCRE_NEWLINE_ANYCRLF
+ /<any> PCRE_NEWLINE_ANY
+
+ Those specifying line ending sequencess are literal strings as shown.
+ This example sets multiline matching with CRLF as the line ending
+ sequence:
+
+ /^abc/m<crlf>
+
+ Details of the meanings of these PCRE options are given in the pcreapi
+ documentation.
+
+ Finding all matches in a string
- Searching for all possible matches within each subject string can be
- requested by the /g or /G modifier. After finding a match, PCRE is
+ Searching for all possible matches within each subject string can be
+ requested by the /g or /G modifier. After finding a match, PCRE is
called again to search the remainder of the subject string. The differ-
ence between /g and /G is that the former uses the startoffset argument
- to pcre_exec() to start searching at a new point within the entire
- string (which is in effect what Perl does), whereas the latter passes
- over a shortened substring. This makes a difference to the matching
+ to pcre_exec() to start searching at a new point within the entire
+ string (which is in effect what Perl does), whereas the latter passes
+ over a shortened substring. This makes a difference to the matching
process if the pattern begins with a lookbehind assertion (including \b
or \B).
- If any call to pcre_exec() in a /g or /G sequence matches an empty
- string, the next call is done with the PCRE_NOTEMPTY and PCRE_ANCHORED
- flags set in order to search for another, non-empty, match at the same
- point. If this second match fails, the start offset is advanced by
- one, and the normal match is retried. This imitates the way Perl han-
+ If any call to pcre_exec() in a /g or /G sequence matches an empty
+ string, the next call is done with the PCRE_NOTEMPTY and PCRE_ANCHORED
+ flags set in order to search for another, non-empty, match at the same
+ point. If this second match fails, the start offset is advanced by
+ one, and the normal match is retried. This imitates the way Perl han-
dles such cases when using the /g modifier or the split() function.
+ Other modifiers
+
There are yet more modifiers for controlling the way pcretest operates.
- The /+ modifier requests that as well as outputting the substring that
- matched the entire pattern, pcretest should in addition output the
- remainder of the subject string. This is useful for tests where the
+ The /+ modifier requests that as well as outputting the substring that
+ matched the entire pattern, pcretest should in addition output the
+ remainder of the subject string. This is useful for tests where the
subject contains multiple copies of the same substring.
+ The /B modifier is a debugging feature. It requests that pcretest out-
+ put a representation of the compiled byte code after compilation. Nor-
+ mally this information contains length and offset values; however, if
+ /Z is also present, this data is replaced by spaces. This is a special
+ feature for use in the automatic test scripts; it ensures that the same
+ output is generated for different internal link sizes.
+
The /L modifier must be followed directly by the name of a locale, for
example,
pattern. If the pattern is studied, the results of that are also out-
put.
- The /D modifier is a PCRE debugging feature, which also assumes /I. 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 /D modifier is a PCRE debugging feature, and is equivalent to /BI,
+ that is, both the /B and the /I modifiers.
The /F modifier causes pcretest to flip the byte order of the fields in
the compiled pattern that contain 2-byte and 4-byte numbers. This
nary" regular expressions, you probably don't need any of these. The
following escapes are recognized:
- \a alarm (= BEL)
- \b backspace
- \e escape
- \f formfeed
- \n newline
- \r carriage return
- \t tab
- \v vertical tab
+ \a alarm (BEL, \x07)
+ \b backspace (\x08)
+ \e escape (\x27)
+ \f formfeed (\x0c)
+ \n newline (\x0a)
+ \qdd set the PCRE_MATCH_LIMIT limit to dd
+ (any number of digits)
+ \r carriage return (\x0d)
+ \t tab (\x09)
+ \v vertical tab (\x0b)
\nnn octal character (up to 3 octal digits)
\xhh hexadecimal character (up to 2 hex digits)
\x{hh...} hexadecimal character, any number of digits
in UTF-8 mode
\A pass the PCRE_ANCHORED option to pcre_exec()
+ or pcre_dfa_exec()
\B pass the PCRE_NOTBOL option to pcre_exec()
+ or pcre_dfa_exec()
\Cdd call pcre_copy_substring() for substring dd
after a successful match (number less than 32)
\Cname call pcre_copy_named_substring() for substring
ated by next non-alphanumeric character)
\L call pcre_get_substringlist() after a
successful match
- \M discover the minimum MATCH_LIMIT setting
+ \M discover the minimum MATCH_LIMIT and
+ MATCH_LIMIT_RECURSION settings
\N pass the PCRE_NOTEMPTY option to pcre_exec()
+ or pcre_dfa_exec()
\Odd set the size of the output vector passed to
pcre_exec() to dd (any number of digits)
\P pass the PCRE_PARTIAL option to pcre_exec()
or pcre_dfa_exec()
+ \Qdd set the PCRE_MATCH_LIMIT_RECURSION limit to dd
+ (any number of digits)
\R pass the PCRE_DFA_RESTART option to pcre_dfa_exec()
\S output details of memory get/free calls during matching
\Z pass the PCRE_NOTEOL option to pcre_exec()
+ or pcre_dfa_exec()
\? pass the PCRE_NO_UTF8_CHECK option to
- pcre_exec()
+ pcre_exec() or pcre_dfa_exec()
\>dd start the match at offset dd (any number of digits);
this sets the startoffset argument for pcre_exec()
+ or pcre_dfa_exec()
+ \<cr> pass the PCRE_NEWLINE_CR option to pcre_exec()
+ or pcre_dfa_exec()
+ \<lf> pass the PCRE_NEWLINE_LF option to pcre_exec()
+ or pcre_dfa_exec()
+ \<crlf> pass the PCRE_NEWLINE_CRLF option to pcre_exec()
+ or pcre_dfa_exec()
+ \<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to pcre_exec()
+ or pcre_dfa_exec()
+ \<any> pass the PCRE_NEWLINE_ANY option to pcre_exec()
+ or pcre_dfa_exec()
+
+ The escapes that specify line ending sequences are literal strings,
+ exactly as shown. No more than one newline setting should be present in
+ any data line.
A backslash followed by anything else just escapes the anything else.
If the very last character is a backslash, it is ignored. This gives a
nates the data input.
If \M is present, pcretest calls pcre_exec() several times, with dif-
- ferent values in the match_limit field of the pcre_extra data struc-
- ture, until it finds the minimum number that is needed for pcre_exec()
- to complete. This number is a measure of the amount of recursion and
- backtracking that takes place, and checking it out can be instructive.
- For most simple matches, the number is quite small, but for patterns
- with very large numbers of matching possibilities, it can become large
- very quickly with increasing length of subject string.
-
- When \O is used, the value specified may be higher or lower than the
+ ferent values in the match_limit and match_limit_recursion fields of
+ the pcre_extra data structure, until it finds the minimum numbers for
+ each parameter that allow pcre_exec() to complete. The match_limit num-
+ ber is a measure of the amount of backtracking that takes place, and
+ checking it out can be instructive. For most simple matches, the number
+ is quite small, but for patterns with very large numbers of matching
+ possibilities, it can become large very quickly with increasing length
+ of subject string. The match_limit_recursion number is a measure of how
+ much stack (or, if PCRE is compiled with NO_RECURSE, how much heap)
+ memory is needed to complete the match attempt.
+
+ When \O is used, the value specified may be higher or lower than the
size set by the -O command line option (or defaulted to 45); \O applies
only to the call of pcre_exec() for the line in which it appears.
- If the /P modifier was present on the pattern, causing the POSIX wrap-
- per API to be used, only \B and \Z have any effect, causing REG_NOTBOL
- and REG_NOTEOL to be passed to regexec() respectively.
+ If the /P modifier was present on the pattern, causing the POSIX wrap-
+ per API to be used, the only option-setting sequences that have any
+ effect are \B and \Z, causing REG_NOTBOL and REG_NOTEOL, respectively,
+ to be passed to regexec().
The use of \x{hh...} to represent UTF-8 characters is not dependent on
the use of the /8 modifier on the pattern. It is recognized always.
is an example of an interactive pcretest run.
$ pcretest
- PCRE version 5.00 07-Sep-2004
+ PCRE version 7.0 30-Nov-2006
re> /^abc(\d+)/
data> abc123
If the strings contain any non-printing characters, they are output as
\0x escapes, or as \x{...} escapes if the /8 modifier was present on
- the pattern. If the pattern has the /+ modifier, the output for sub-
- string 0 is followed by the the rest of the subject string, identified
- by "0+" like this:
+ the pattern. See below for the definition of non-printing characters.
+ If the pattern has the /+ modifier, the output for substring 0 is fol-
+ lowed by the the rest of the subject string, identified by "0+" like
+ this:
re> /cat/+
data> cataract
0: cat
0+ aract
- If the pattern has the /g or /G modifier, the results of successive
+ If the pattern has the /g or /G modifier, the results of successive
matching attempts are output in sequence, like this:
re> /\Bi(\w\w)/g
"No match" is output only if the first match attempt fails.
- If any of the sequences \C, \G, or \L are present in a data line that
- is successfully matched, the substrings extracted by the convenience
+ If any of the sequences \C, \G, or \L are present in a data line that
+ is successfully matched, the substrings extracted by the convenience
functions are output with C, G, or L after the string number instead of
a colon. This is in addition to the normal full list. The string length
- (that is, the return from the extraction function) is given in paren-
+ (that is, the return from the extraction function) is given in paren-
theses after each string for \C and \G.
- Note that while patterns can be continued over several lines (a plain
+ Note that whereas patterns can be continued over several lines (a plain
">" prompt is used for continuations), data lines may not. However new-
- lines can be included in data by means of the \n escape.
+ lines can be included in data by means of the \n escape (or \r, \r\n,
+ etc., depending on the newline sequence setting).
OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION
(Using the normal matching function on this data finds only "tang".)
The longest matching string is always given first (and numbered zero).
- If /gP is present on the pattern, the search for further matches
- resumes at the end of the longest match. For example:
+ If /g is present on the pattern, the search for further matches resumes
+ at the end of the longest match. For example:
re> /(tang|tangerine|tan)/g
data> yellow tangerine and tangy sultana\D
can restart the match with additional subject data by means of the \R
escape sequence. For example:
- re> /^?(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)$/
+ re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
data> 23ja\P\D
Partial match: 23ja
data> n05\R\D
the pcrecallout documentation.
+NON-PRINTING CHARACTERS
+
+ When pcretest is outputting text in the compiled version of a pattern,
+ bytes other than 32-126 are always treated as non-printing characters
+ are are therefore shown as hex escapes.
+
+ When pcretest is outputting text that is a matched part of a subject
+ string, it behaves in the same way, unless a different locale has been
+ set for the pattern (using the /L modifier). In this case, the
+ isprint() function to distinguish printing and non-printing characters.
+
+
SAVING AND RELOADING COMPILED PATTERNS
The facilities described in this section are not available when the
a file that is not in the correct format, the result is undefined.
+SEE ALSO
+
+ pcre(3), pcreapi(3), pcrecallout(3), pcrematching(3), pcrepartial(d),
+ pcrepattern(3), pcreprecompile(3).
+
+
AUTHOR
Philip Hazel
- University Computing Service,
- Cambridge CB2 3QG, England.
+ University Computing Service
+ Cambridge CB2 3QH, England.
+
+
+REVISION
-Last updated: 28 February 2005
-Copyright (c) 1997-2005 University of Cambridge.
+ Last updated: 24 April 2007
+ Copyright (c) 1997-2007 University of Cambridge.
git://git.exim.org / exim.git / blobdiff