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PCRETEST(1) General Commands Manual PCRETEST(1)
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NAME
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pcretest - a program for testing Perl-compatible regular expressions.
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SYNOPSIS
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pcretest [options] [input file [output file]]
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pcretest was written as a test program for the PCRE regular expression
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library itself, but it can also be used for experimenting with regular
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expressions. This document describes the features of the test program;
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for details of the regular expressions themselves, see the pcrepattern
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documentation. For details of the PCRE library function calls and their
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options, see the pcreapi , pcre16 and pcre32 documentation.
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The input for pcretest is a sequence of regular expression patterns and
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strings to be matched, as described below. The output shows the result
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of each match. Options on the command line and the patterns control
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PCRE options and exactly what is output.
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As PCRE has evolved, it has acquired many different features, and as a
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result, pcretest now has rather a lot of obscure options for testing
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every possible feature. Some of these options are specifically designed
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for use in conjunction with the test script and data files that are
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distributed as part of PCRE, and are unlikely to be of use otherwise.
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They are all documented here, but without much justification.
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INPUT DATA FORMAT
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Input to pcretest is processed line by line, either by calling the C
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library's fgets() function, or via the libreadline library (see below).
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In Unix-like environments, fgets() treats any bytes other than newline
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as data characters. However, in some Windows environments character 26
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(hex 1A) causes an immediate end of file, and no further data is read.
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For maximum portability, therefore, it is safest to use only ASCII
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characters in pcretest input files.
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The input is processed using using C's string functions, so must not
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contain binary zeroes, even though in Unix-like environments, fgets()
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treats any bytes other than newline as data characters.
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PCRE's 8-BIT, 16-BIT AND 32-BIT LIBRARIES
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From release 8.30, two separate PCRE libraries can be built. The origi-
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nal one supports 8-bit character strings, whereas the newer 16-bit li-
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brary supports character strings encoded in 16-bit units. From release
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8.32, a third library can be built, supporting character strings en-
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coded in 32-bit units. The pcretest program can be used to test all
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three libraries. However, it is itself still an 8-bit program, reading
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8-bit input and writing 8-bit output. When testing the 16-bit or
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32-bit library, the patterns and data strings are converted to 16- or
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32-bit format before being passed to the PCRE library functions. Re-
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sults are converted to 8-bit for output.
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References to functions and structures of the form pcre[16|32]_xx below
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mean "pcre_xx when using the 8-bit library, pcre16_xx when using the
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16-bit library, or pcre32_xx when using the 32-bit library".
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COMMAND LINE OPTIONS
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-8 If the 8-bit library has been built, this option causes it to
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be used (this is the default). If the 8-bit library has not
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been built, this option causes an error.
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-16 If the 16-bit library has been built, this option causes it
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to be used. If only the 16-bit library has been built, this
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is the default. If the 16-bit library has not been built,
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this option causes an error.
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-32 If the 32-bit library has been built, this option causes it
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to be used. If only the 32-bit library has been built, this
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is the default. If the 32-bit library has not been built,
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this option causes an error.
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-b Behave as if each pattern has the /B (show byte code) modi-
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fier; the internal form is output after compilation.
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-C Output the version number of the PCRE library, and all avail-
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able information about the optional features that are in-
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cluded, and then exit with zero exit code. All other options
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are ignored.
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-C option Output information about a specific build-time option, then
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exit. This functionality is intended for use in scripts such
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as RunTest. The following options output the value and set
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the exit code as indicated:
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ebcdic-nl the code for LF (= NL) in an EBCDIC environment:
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0x15 or 0x25
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0 if used in an ASCII environment
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exit code is always 0
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linksize the configured internal link size (2, 3, or 4)
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exit code is set to the link size
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newline the default newline setting:
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CR, LF, CRLF, ANYCRLF, or ANY
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exit code is always 0
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bsr the default setting for what \R matches:
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ANYCRLF or ANY
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exit code is always 0
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The following options output 1 for true or 0 for false, and
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set the exit code to the same value:
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ebcdic compiled for an EBCDIC environment
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jit just-in-time support is available
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pcre16 the 16-bit library was built
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pcre32 the 32-bit library was built
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pcre8 the 8-bit library was built
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ucp Unicode property support is available
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utf UTF-8 and/or UTF-16 and/or UTF-32 support
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is available
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If an unknown option is given, an error message is output;
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the exit code is 0.
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-d Behave as if each pattern has the /D (debug) modifier; the
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internal form and information about the compiled pattern is
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output after compilation; -d is equivalent to -b -i.
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-dfa Behave as if each data line contains the \D escape sequence;
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this causes the alternative matching function,
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pcre[16|32]_dfa_exec(), to be used instead of the standard
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pcre[16|32]_exec() function (more detail is given below).
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-help Output a brief summary these options and then exit.
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-i Behave as if each pattern has the /I modifier; information
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about the compiled pattern is given after compilation.
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-M Behave as if each data line contains the \M escape sequence;
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this causes PCRE to discover the minimum MATCH_LIMIT and
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MATCH_LIMIT_RECURSION settings by calling pcre[16|32]_exec()
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repeatedly with different limits.
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-m Output the size of each compiled pattern after it has been
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compiled. This is equivalent to adding /M to each regular ex-
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pression. The size is given in bytes for both libraries.
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-O Behave as if each pattern has the /O modifier, that is dis-
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able auto-possessification for all patterns.
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-o osize Set the number of elements in the output vector that is used
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when calling pcre[16|32]_exec() or pcre[16|32]_dfa_exec() to
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be osize. The default value is 45, which is enough for 14
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capturing subexpressions for pcre[16|32]_exec() or 22 differ-
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ent matches for pcre[16|32]_dfa_exec(). The vector size can
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be changed for individual matching calls by including \O in
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the data line (see below).
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-p Behave as if each pattern has the /P modifier; the POSIX
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wrapper API is used to call PCRE. None of the other options
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has any effect when -p is set. This option can be used only
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with the 8-bit library.
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-q Do not output the version number of pcretest at the start of
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execution.
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-S size On Unix-like systems, set the size of the run-time stack to
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size megabytes.
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-s or -s+ Behave as if each pattern has the /S modifier; in other
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words, force each pattern to be studied. If -s+ is used, all
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the JIT compile options are passed to pcre[16|32]_study(),
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causing just-in-time optimization to be set up if it is
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available, for both full and partial matching. Specific JIT
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compile options can be selected by following -s+ with a digit
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in the range 1 to 7, which selects the JIT compile modes as
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follows:
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1 normal match only
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2 soft partial match only
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3 normal match and soft partial match
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4 hard partial match only
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6 soft and hard partial match
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7 all three modes (default)
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If -s++ is used instead of -s+ (with or without a following
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digit), the text "(JIT)" is added to the first output line
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after a match or no match when JIT-compiled code was actually
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used.
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Note that there are pattern options that can override -s, ei-
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ther specifying no studying at all, or suppressing JIT compi-
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lation.
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If the /I or /D option is present on a pattern (requesting
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output about the compiled pattern), information about the re-
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sult of studying is not included when studying is caused only
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by -s and neither -i nor -d is present on the command line.
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This behaviour means that the output from tests that are run
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with and without -s should be identical, except when options
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that output information about the actual running of a match
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are set.
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The -M, -t, and -tm options, which give information about re-
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sources used, are likely to produce different output with and
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without -s. Output may also differ if the /C option is
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present on an individual pattern. This uses callouts to trace
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the the matching process, and this may be different between
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studied and non-studied patterns. If the pattern contains
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(*MARK) items there may also be differences, for the same
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reason. The -s command line option can be overridden for spe-
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cific patterns that should never be studied (see the /S pat-
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tern modifier below).
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-t Run each compile, study, and match many times with a timer,
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and output the resulting times per compile, study, or match
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(in milliseconds). Do not set -m with -t, because you will
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then get the size output a zillion times, and the timing will
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be distorted. You can control the number of iterations that
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are used for timing by following -t with a number (as a sepa-
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rate item on the command line). For example, "-t 1000" iter-
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ates 1000 times. The default is to iterate 500000 times.
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-tm This is like -t except that it times only the matching phase,
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not the compile or study phases.
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-T -TM These behave like -t and -tm, but in addition, at the end of
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a run, the total times for all compiles, studies, and matches
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are output.
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DESCRIPTION
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If pcretest is given two filename arguments, it reads from the first
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and writes to the second. If it is given only one filename argument, it
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reads from that file and writes to stdout. Otherwise, it reads from
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stdin and writes to stdout, and prompts for each line of input, using
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"re>" to prompt for regular expressions, and "data>" to prompt for data
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lines.
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When pcretest is built, a configuration option can specify that it
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should be linked with the libreadline library. When this is done, if
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the input is from a terminal, it is read using the readline() function.
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This provides line-editing and history facilities. The output from the
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-help option states whether or not readline() will be used.
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The program handles any number of sets of input on a single input file.
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Each set starts with a regular expression, and continues with any num-
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ber of data lines to be matched against that pattern.
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Each data line is matched separately and independently. If you want to
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do multi-line matches, you have to use the \n escape sequence (or \r or
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\r\n, etc., depending on the newline setting) in a single line of input
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to encode the newline sequences. There is no limit on the length of
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data lines; the input buffer is automatically extended if it is too
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small.
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An empty line signals the end of the data lines, at which point a new
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regular expression is read. The regular expressions are given enclosed
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in any non-alphanumeric delimiters other than backslash, for example:
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/(a|bc)x+yz/
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White space before the initial delimiter is ignored. A regular expres-
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sion may be continued over several input lines, in which case the new-
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line characters are included within it. It is possible to include the
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delimiter within the pattern by escaping it, for example
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/abc\/def/
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If you do so, the escape and the delimiter form part of the pattern,
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but since delimiters are always non-alphanumeric, this does not affect
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its interpretation. If the terminating delimiter is immediately fol-
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lowed by a backslash, for example,
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/abc/\
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then a backslash is added to the end of the pattern. This is done to
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provide a way of testing the error condition that arises if a pattern
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finishes with a backslash, because
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/abc\/
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is interpreted as the first line of a pattern that starts with "abc/",
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causing pcretest to read the next line as a continuation of the regular
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expression.
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PATTERN MODIFIERS
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A pattern may be followed by any number of modifiers, which are mostly
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single characters, though some of these can be qualified by further
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characters. Following Perl usage, these are referred to below as, for
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example, "the /i modifier", even though the delimiter of the pattern
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need not always be a slash, and no slash is used when writing modi-
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fiers. White space may appear between the final pattern delimiter and
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the first modifier, and between the modifiers themselves. For refer-
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ence, here is a complete list of modifiers. They fall into several
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groups that are described in detail in the following sections.
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/8 set UTF mode
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/9 set PCRE_NEVER_UTF (locks out UTF mode)
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/? disable UTF validity check
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/+ show remainder of subject after match
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/= show all captures (not just those that are set)
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/A set PCRE_ANCHORED
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/B show compiled code
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/C set PCRE_AUTO_CALLOUT
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/D same as /B plus /I
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/E set PCRE_DOLLAR_ENDONLY
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/F flip byte order in compiled pattern
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/f set PCRE_FIRSTLINE
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/G find all matches (shorten string)
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/g find all matches (use startoffset)
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/I show information about pattern
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/i set PCRE_CASELESS
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/J set PCRE_DUPNAMES
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/K show backtracking control names
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/L set locale
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/M show compiled memory size
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/m set PCRE_MULTILINE
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/N set PCRE_NO_AUTO_CAPTURE
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/O set PCRE_NO_AUTO_POSSESS
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/P use the POSIX wrapper
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/Q test external stack check function
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/S study the pattern after compilation
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/s set PCRE_DOTALL
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/T select character tables
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/U set PCRE_UNGREEDY
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/W set PCRE_UCP
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/X set PCRE_EXTRA
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/x set PCRE_EXTENDED
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/Y set PCRE_NO_START_OPTIMIZE
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/Z don't show lengths in /B output
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/<any> set PCRE_NEWLINE_ANY
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/<anycrlf> set PCRE_NEWLINE_ANYCRLF
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/<cr> set PCRE_NEWLINE_CR
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/<crlf> set PCRE_NEWLINE_CRLF
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/<lf> set PCRE_NEWLINE_LF
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/<bsr_anycrlf> set PCRE_BSR_ANYCRLF
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/<bsr_unicode> set PCRE_BSR_UNICODE
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/<JS> set PCRE_JAVASCRIPT_COMPAT
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Perl-compatible modifiers
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The /i, /m, /s, and /x modifiers set the PCRE_CASELESS, PCRE_MULTILINE,
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PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when
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pcre[16|32]_compile() is called. These four modifier letters have the
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same effect as they do in Perl. For example:
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/caseless/i
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Modifiers for other PCRE options
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The following table shows additional modifiers for setting PCRE com-
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pile-time options that do not correspond to anything in Perl:
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/8 PCRE_UTF8 ) when using the 8-bit
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/? PCRE_NO_UTF8_CHECK ) library
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/8 PCRE_UTF16 ) when using the 16-bit
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/? PCRE_NO_UTF16_CHECK ) library
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/8 PCRE_UTF32 ) when using the 32-bit
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/? PCRE_NO_UTF32_CHECK ) library
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/9 PCRE_NEVER_UTF
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/A PCRE_ANCHORED
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/C PCRE_AUTO_CALLOUT
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/E PCRE_DOLLAR_ENDONLY
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/f PCRE_FIRSTLINE
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/J PCRE_DUPNAMES
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/N PCRE_NO_AUTO_CAPTURE
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/O PCRE_NO_AUTO_POSSESS
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/U PCRE_UNGREEDY
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/W PCRE_UCP
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/X PCRE_EXTRA
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/Y PCRE_NO_START_OPTIMIZE
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/<any> PCRE_NEWLINE_ANY
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/<anycrlf> PCRE_NEWLINE_ANYCRLF
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/<cr> PCRE_NEWLINE_CR
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/<crlf> PCRE_NEWLINE_CRLF
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/<lf> PCRE_NEWLINE_LF
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/<bsr_anycrlf> PCRE_BSR_ANYCRLF
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/<bsr_unicode> PCRE_BSR_UNICODE
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/<JS> PCRE_JAVASCRIPT_COMPAT
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The modifiers that are enclosed in angle brackets are literal strings
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as shown, including the angle brackets, but the letters within can be
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in either case. This example sets multiline matching with CRLF as the
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line ending sequence:
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/^abc/m<CRLF>
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As well as turning on the PCRE_UTF8/16/32 option, the /8 modifier
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causes all non-printing characters in output strings to be printed us-
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ing the \x{hh...} notation. Otherwise, those less than 0x100 are output
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in hex without the curly brackets.
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Full details of the PCRE options are given in the pcreapi documenta-
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tion.
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Finding all matches in a string
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Searching for all possible matches within each subject string can be
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requested by the /g or /G modifier. After finding a match, PCRE is
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called again to search the remainder of the subject string. The differ-
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ence between /g and /G is that the former uses the startoffset argument
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to pcre[16|32]_exec() to start searching at a new point within the en-
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tire string (which is in effect what Perl does), whereas the latter
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passes over a shortened substring. This makes a difference to the
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matching process if the pattern begins with a lookbehind assertion (in-
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cluding \b or \B).
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If any call to pcre[16|32]_exec() in a /g or /G sequence matches an
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empty string, the next call is done with the PCRE_NOTEMPTY_ATSTART and
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PCRE_ANCHORED flags set in order to search for another, non-empty,
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match at the same point. If this second match fails, the start offset
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is advanced, and the normal match is retried. This imitates the way
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Perl handles such cases when using the /g modifier or the split() func-
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| 422 |
tion. Normally, the start offset is advanced by one character, but if
|
| 423 |
the newline convention recognizes CRLF as a newline, and the current
|
| 424 |
character is CR followed by LF, an advance of two is used.
|
| 425 |
|
| 426 |
Other modifiers
|
| 427 |
|
| 428 |
There are yet more modifiers for controlling the way pcretest operates.
|
| 429 |
|
| 430 |
The /+ modifier requests that as well as outputting the substring that
|
| 431 |
matched the entire pattern, pcretest should in addition output the re-
|
| 432 |
mainder of the subject string. This is useful for tests where the sub-
|
| 433 |
ject contains multiple copies of the same substring. If the + modifier
|
| 434 |
appears twice, the same action is taken for captured substrings. In
|
| 435 |
each case the remainder is output on the following line with a plus
|
| 436 |
character following the capture number. Note that this modifier must
|
| 437 |
not immediately follow the /S modifier because /S+ and /S++ have other
|
| 438 |
meanings.
|
| 439 |
|
| 440 |
The /= modifier requests that the values of all potential captured
|
| 441 |
parentheses be output after a match. By default, only those up to the
|
| 442 |
highest one actually used in the match are output (corresponding to the
|
| 443 |
return code from pcre[16|32]_exec()). Values in the offsets vector cor-
|
| 444 |
responding to higher numbers should be set to -1, and these are output
|
| 445 |
as "<unset>". This modifier gives a way of checking that this is hap-
|
| 446 |
pening.
|
| 447 |
|
| 448 |
The /B modifier is a debugging feature. It requests that pcretest out-
|
| 449 |
put a representation of the compiled code after compilation. Normally
|
| 450 |
this information contains length and offset values; however, if /Z is
|
| 451 |
also present, this data is replaced by spaces. This is a special fea-
|
| 452 |
ture for use in the automatic test scripts; it ensures that the same
|
| 453 |
output is generated for different internal link sizes.
|
| 454 |
|
| 455 |
The /D modifier is a PCRE debugging feature, and is equivalent to /BI,
|
| 456 |
that is, both the /B and the /I modifiers.
|
| 457 |
|
| 458 |
The /F modifier causes pcretest to flip the byte order of the 2-byte
|
| 459 |
and 4-byte fields in the compiled pattern. This facility is for testing
|
| 460 |
the feature in PCRE that allows it to execute patterns that were com-
|
| 461 |
piled on a host with a different endianness. This feature is not avail-
|
| 462 |
able when the POSIX interface to PCRE is being used, that is, when the
|
| 463 |
/P pattern modifier is specified. See also the section about saving and
|
| 464 |
reloading compiled patterns below.
|
| 465 |
|
| 466 |
The /I modifier requests that pcretest output information about the
|
| 467 |
compiled pattern (whether it is anchored, has a fixed first character,
|
| 468 |
and so on). It does this by calling pcre[16|32]_fullinfo() after com-
|
| 469 |
piling a pattern. If the pattern is studied, the results of that are
|
| 470 |
also output. In this output, the word "char" means a non-UTF character,
|
| 471 |
that is, the value of a single data item (8-bit, 16-bit, or 32-bit, de-
|
| 472 |
pending on the library that is being tested).
|
| 473 |
|
| 474 |
The /K modifier requests pcretest to show names from backtracking con-
|
| 475 |
trol verbs that are returned from calls to pcre[16|32]_exec(). It
|
| 476 |
causes pcretest to create a pcre[16|32]_extra block if one has not al-
|
| 477 |
ready been created by a call to pcre[16|32]_study(), and to set the
|
| 478 |
PCRE_EXTRA_MARK flag and the mark field within it, every time that
|
| 479 |
pcre[16|32]_exec() is called. If the variable that the mark field
|
| 480 |
points to is non-NULL for a match, non-match, or partial match,
|
| 481 |
pcretest prints the string to which it points. For a match, this is
|
| 482 |
shown on a line by itself, tagged with "MK:". For a non-match it is
|
| 483 |
added to the message.
|
| 484 |
|
| 485 |
The /L modifier must be followed directly by the name of a locale, for
|
| 486 |
example,
|
| 487 |
|
| 488 |
/pattern/Lfr_FR
|
| 489 |
|
| 490 |
For this reason, it must be the last modifier. The given locale is set,
|
| 491 |
pcre[16|32]_maketables() is called to build a set of character tables
|
| 492 |
for the locale, and this is then passed to pcre[16|32]_compile() when
|
| 493 |
compiling the regular expression. Without an /L (or /T) modifier, NULL
|
| 494 |
is passed as the tables pointer; that is, /L applies only to the ex-
|
| 495 |
pression on which it appears.
|
| 496 |
|
| 497 |
The /M modifier causes the size in bytes of the memory block used to
|
| 498 |
hold the compiled pattern to be output. This does not include the size
|
| 499 |
of the pcre[16|32] block; it is just the actual compiled data. If the
|
| 500 |
pattern is successfully studied with the PCRE_STUDY_JIT_COMPILE option,
|
| 501 |
the size of the JIT compiled code is also output.
|
| 502 |
|
| 503 |
The /Q modifier is used to test the use of pcre_stack_guard. It must be
|
| 504 |
followed by '0' or '1', specifying the return code to be given from an
|
| 505 |
external function that is passed to PCRE and used for stack checking
|
| 506 |
during compilation (see the pcreapi documentation for details).
|
| 507 |
|
| 508 |
The /S modifier causes pcre[16|32]_study() to be called after the ex-
|
| 509 |
pression has been compiled, and the results used when the expression is
|
| 510 |
matched. There are a number of qualifying characters that may follow
|
| 511 |
/S. They may appear in any order.
|
| 512 |
|
| 513 |
If /S is followed by an exclamation mark, pcre[16|32]_study() is called
|
| 514 |
with the PCRE_STUDY_EXTRA_NEEDED option, causing it always to return a
|
| 515 |
pcre_extra block, even when studying discovers no useful information.
|
| 516 |
|
| 517 |
If /S is followed by a second S character, it suppresses studying, even
|
| 518 |
if it was requested externally by the -s command line option. This
|
| 519 |
makes it possible to specify that certain patterns are always studied,
|
| 520 |
and others are never studied, independently of -s. This feature is used
|
| 521 |
in the test files in a few cases where the output is different when the
|
| 522 |
pattern is studied.
|
| 523 |
|
| 524 |
If the /S modifier is followed by a + character, the call to
|
| 525 |
pcre[16|32]_study() is made with all the JIT study options, requesting
|
| 526 |
just-in-time optimization support if it is available, for both normal
|
| 527 |
and partial matching. If you want to restrict the JIT compiling modes,
|
| 528 |
you can follow /S+ with a digit in the range 1 to 7:
|
| 529 |
|
| 530 |
1 normal match only
|
| 531 |
2 soft partial match only
|
| 532 |
3 normal match and soft partial match
|
| 533 |
4 hard partial match only
|
| 534 |
6 soft and hard partial match
|
| 535 |
7 all three modes (default)
|
| 536 |
|
| 537 |
If /S++ is used instead of /S+ (with or without a following digit), the
|
| 538 |
text "(JIT)" is added to the first output line after a match or no
|
| 539 |
match when JIT-compiled code was actually used.
|
| 540 |
|
| 541 |
Note that there is also an independent /+ modifier; it must not be
|
| 542 |
given immediately after /S or /S+ because this will be misinterpreted.
|
| 543 |
|
| 544 |
If JIT studying is successful, the compiled JIT code will automatically
|
| 545 |
be used when pcre[16|32]_exec() is run, except when incompatible run-
|
| 546 |
time options are specified. For more details, see the pcrejit documen-
|
| 547 |
tation. See also the \J escape sequence below for a way of setting the
|
| 548 |
size of the JIT stack.
|
| 549 |
|
| 550 |
Finally, if /S is followed by a minus character, JIT compilation is
|
| 551 |
suppressed, even if it was requested externally by the -s command line
|
| 552 |
option. This makes it possible to specify that JIT is never to be used
|
| 553 |
for certain patterns.
|
| 554 |
|
| 555 |
The /T modifier must be followed by a single digit. It causes a spe-
|
| 556 |
cific set of built-in character tables to be passed to pcre[16|32]_com-
|
| 557 |
pile(). It is used in the standard PCRE tests to check behaviour with
|
| 558 |
different character tables. The digit specifies the tables as follows:
|
| 559 |
|
| 560 |
0 the default ASCII tables, as distributed in
|
| 561 |
pcre_chartables.c.dist
|
| 562 |
1 a set of tables defining ISO 8859 characters
|
| 563 |
|
| 564 |
In table 1, some characters whose codes are greater than 128 are iden-
|
| 565 |
tified as letters, digits, spaces, etc.
|
| 566 |
|
| 567 |
Using the POSIX wrapper API
|
| 568 |
|
| 569 |
The /P modifier causes pcretest to call PCRE via the POSIX wrapper API
|
| 570 |
rather than its native API. This supports only the 8-bit library. When
|
| 571 |
/P is set, the following modifiers set options for the regcomp() func-
|
| 572 |
tion:
|
| 573 |
|
| 574 |
/i REG_ICASE
|
| 575 |
/m REG_NEWLINE
|
| 576 |
/N REG_NOSUB
|
| 577 |
/s REG_DOTALL )
|
| 578 |
/U REG_UNGREEDY ) These options are not part of
|
| 579 |
/W REG_UCP ) the POSIX standard
|
| 580 |
/8 REG_UTF8 )
|
| 581 |
|
| 582 |
The /+ modifier works as described above. All other modifiers are ig-
|
| 583 |
nored.
|
| 584 |
|
| 585 |
Locking out certain modifiers
|
| 586 |
|
| 587 |
PCRE can be compiled with or without support for certain features such
|
| 588 |
as UTF-8/16/32 or Unicode properties. Accordingly, the standard tests
|
| 589 |
are split up into a number of different files that are selected for
|
| 590 |
running depending on which features are available. When updating the
|
| 591 |
tests, it is all too easy to put a new test into the wrong file by mis-
|
| 592 |
take; for example, to put a test that requires UTF support into a file
|
| 593 |
that is used when it is not available. To help detect such mistakes as
|
| 594 |
early as possible, there is a facility for locking out specific modi-
|
| 595 |
fiers. If an input line for pcretest starts with the string "< forbid "
|
| 596 |
the following sequence of characters is taken as a list of forbidden
|
| 597 |
modifiers. For example, in the test files that must not use UTF or Uni-
|
| 598 |
code property support, this line appears:
|
| 599 |
|
| 600 |
< forbid 8W
|
| 601 |
|
| 602 |
This locks out the /8 and /W modifiers. An immediate error is given if
|
| 603 |
they are subsequently encountered. If the character string contains <
|
| 604 |
but not >, all the multi-character modifiers that begin with < are
|
| 605 |
locked out. Otherwise, such modifiers must be explicitly listed, for
|
| 606 |
example:
|
| 607 |
|
| 608 |
< forbid <JS><cr>
|
| 609 |
|
| 610 |
There must be a single space between < and "forbid" for this feature to
|
| 611 |
be recognised. If there is not, the line is interpreted either as a re-
|
| 612 |
quest to re-load a pre-compiled pattern (see "SAVING AND RELOADING COM-
|
| 613 |
PILED PATTERNS" below) or, if there is a another < character, as a pat-
|
| 614 |
tern that uses < as its delimiter.
|
| 615 |
|
| 616 |
|
| 617 |
DATA LINES
|
| 618 |
|
| 619 |
Before each data line is passed to pcre[16|32]_exec(), leading and
|
| 620 |
trailing white space is removed, and it is then scanned for \ escapes.
|
| 621 |
Some of these are pretty esoteric features, intended for checking out
|
| 622 |
some of the more complicated features of PCRE. If you are just testing
|
| 623 |
"ordinary" regular expressions, you probably don't need any of these.
|
| 624 |
The following escapes are recognized:
|
| 625 |
|
| 626 |
\a alarm (BEL, \x07)
|
| 627 |
\b backspace (\x08)
|
| 628 |
\e escape (\x27)
|
| 629 |
\f form feed (\x0c)
|
| 630 |
\n newline (\x0a)
|
| 631 |
\qdd set the PCRE_MATCH_LIMIT limit to dd
|
| 632 |
(any number of digits)
|
| 633 |
\r carriage return (\x0d)
|
| 634 |
\t tab (\x09)
|
| 635 |
\v vertical tab (\x0b)
|
| 636 |
\nnn octal character (up to 3 octal digits); always
|
| 637 |
a byte unless > 255 in UTF-8 or 16-bit or 32-bit mode
|
| 638 |
\o{dd...} octal character (any number of octal digits}
|
| 639 |
\xhh hexadecimal byte (up to 2 hex digits)
|
| 640 |
\x{hh...} hexadecimal character (any number of hex digits)
|
| 641 |
\A pass the PCRE_ANCHORED option to pcre[16|32]_exec()
|
| 642 |
or pcre[16|32]_dfa_exec()
|
| 643 |
\B pass the PCRE_NOTBOL option to pcre[16|32]_exec()
|
| 644 |
or pcre[16|32]_dfa_exec()
|
| 645 |
\Cdd call pcre[16|32]_copy_substring() for substring dd
|
| 646 |
after a successful match (number less than 32)
|
| 647 |
\Cname call pcre[16|32]_copy_named_substring() for substring
|
| 648 |
"name" after a successful match (name termin-
|
| 649 |
ated by next non alphanumeric character)
|
| 650 |
\C+ show the current captured substrings at callout
|
| 651 |
time
|
| 652 |
\C- do not supply a callout function
|
| 653 |
\C!n return 1 instead of 0 when callout number n is
|
| 654 |
reached
|
| 655 |
\C!n!m return 1 instead of 0 when callout number n is
|
| 656 |
reached for the nth time
|
| 657 |
\C*n pass the number n (may be negative) as callout
|
| 658 |
data; this is used as the callout return value
|
| 659 |
\D use the pcre[16|32]_dfa_exec() match function
|
| 660 |
\F only shortest match for pcre[16|32]_dfa_exec()
|
| 661 |
\Gdd call pcre[16|32]_get_substring() for substring dd
|
| 662 |
after a successful match (number less than 32)
|
| 663 |
\Gname call pcre[16|32]_get_named_substring() for substring
|
| 664 |
"name" after a successful match (name termin-
|
| 665 |
ated by next non-alphanumeric character)
|
| 666 |
\Jdd set up a JIT stack of dd kilobytes maximum (any
|
| 667 |
number of digits)
|
| 668 |
\L call pcre[16|32]_get_substringlist() after a
|
| 669 |
successful match
|
| 670 |
\M discover the minimum MATCH_LIMIT and
|
| 671 |
MATCH_LIMIT_RECURSION settings
|
| 672 |
\N pass the PCRE_NOTEMPTY option to pcre[16|32]_exec()
|
| 673 |
or pcre[16|32]_dfa_exec(); if used twice, pass the
|
| 674 |
PCRE_NOTEMPTY_ATSTART option
|
| 675 |
\Odd set the size of the output vector passed to
|
| 676 |
pcre[16|32]_exec() to dd (any number of digits)
|
| 677 |
\P pass the PCRE_PARTIAL_SOFT option to pcre[16|32]_exec()
|
| 678 |
or pcre[16|32]_dfa_exec(); if used twice, pass the
|
| 679 |
PCRE_PARTIAL_HARD option
|
| 680 |
\Qdd set the PCRE_MATCH_LIMIT_RECURSION limit to dd
|
| 681 |
(any number of digits)
|
| 682 |
\R pass the PCRE_DFA_RESTART option to pcre[16|32]_dfa_exec()
|
| 683 |
\S output details of memory get/free calls during matching
|
| 684 |
\Y pass the PCRE_NO_START_OPTIMIZE option to
|
| 685 |
pcre[16|32]_exec()
|
| 686 |
or pcre[16|32]_dfa_exec()
|
| 687 |
\Z pass the PCRE_NOTEOL option to pcre[16|32]_exec()
|
| 688 |
or pcre[16|32]_dfa_exec()
|
| 689 |
\? pass the PCRE_NO_UTF[8|16|32]_CHECK option to
|
| 690 |
pcre[16|32]_exec() or pcre[16|32]_dfa_exec()
|
| 691 |
\>dd start the match at offset dd (optional "-"; then
|
| 692 |
any number of digits); this sets the startoffset
|
| 693 |
argument for pcre[16|32]_exec() or
|
| 694 |
pcre[16|32]_dfa_exec()
|
| 695 |
\<cr> pass the PCRE_NEWLINE_CR option to pcre[16|32]_exec()
|
| 696 |
or pcre[16|32]_dfa_exec()
|
| 697 |
\<lf> pass the PCRE_NEWLINE_LF option to pcre[16|32]_exec()
|
| 698 |
or pcre[16|32]_dfa_exec()
|
| 699 |
\<crlf> pass the PCRE_NEWLINE_CRLF option to pcre[16|32]_exec()
|
| 700 |
or pcre[16|32]_dfa_exec()
|
| 701 |
\<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to pcre[16|32]_exec()
|
| 702 |
or pcre[16|32]_dfa_exec()
|
| 703 |
\<any> pass the PCRE_NEWLINE_ANY option to pcre[16|32]_exec()
|
| 704 |
or pcre[16|32]_dfa_exec()
|
| 705 |
|
| 706 |
The use of \x{hh...} is not dependent on the use of the /8 modifier on
|
| 707 |
the pattern. It is recognized always. There may be any number of hexa-
|
| 708 |
decimal digits inside the braces; invalid values provoke error mes-
|
| 709 |
sages.
|
| 710 |
|
| 711 |
Note that \xhh specifies one byte rather than one character in UTF-8
|
| 712 |
mode; this makes it possible to construct invalid UTF-8 sequences for
|
| 713 |
testing purposes. On the other hand, \x{hh} is interpreted as a UTF-8
|
| 714 |
character in UTF-8 mode, generating more than one byte if the value is
|
| 715 |
greater than 127. When testing the 8-bit library not in UTF-8 mode,
|
| 716 |
\x{hh} generates one byte for values less than 256, and causes an error
|
| 717 |
for greater values.
|
| 718 |
|
| 719 |
In UTF-16 mode, all 4-digit \x{hhhh} values are accepted. This makes it
|
| 720 |
possible to construct invalid UTF-16 sequences for testing purposes.
|
| 721 |
|
| 722 |
In UTF-32 mode, all 4- to 8-digit \x{...} values are accepted. This
|
| 723 |
makes it possible to construct invalid UTF-32 sequences for testing
|
| 724 |
purposes.
|
| 725 |
|
| 726 |
The escapes that specify line ending sequences are literal strings, ex-
|
| 727 |
actly as shown. No more than one newline setting should be present in
|
| 728 |
any data line.
|
| 729 |
|
| 730 |
A backslash followed by anything else just escapes the anything else.
|
| 731 |
If the very last character is a backslash, it is ignored. This gives a
|
| 732 |
way of passing an empty line as data, since a real empty line termi-
|
| 733 |
nates the data input.
|
| 734 |
|
| 735 |
The \J escape provides a way of setting the maximum stack size that is
|
| 736 |
used by the just-in-time optimization code. It is ignored if JIT opti-
|
| 737 |
mization is not being used. Providing a stack that is larger than the
|
| 738 |
default 32K is necessary only for very complicated patterns.
|
| 739 |
|
| 740 |
If \M is present, pcretest calls pcre[16|32]_exec() several times, with
|
| 741 |
different values in the match_limit and match_limit_recursion fields of
|
| 742 |
the pcre[16|32]_extra data structure, until it finds the minimum num-
|
| 743 |
bers for each parameter that allow pcre[16|32]_exec() to complete with-
|
| 744 |
out error. Because this is testing a specific feature of the normal in-
|
| 745 |
terpretive pcre[16|32]_exec() execution, the use of any JIT optimiza-
|
| 746 |
tion that might have been set up by the /S+ qualifier of -s+ option is
|
| 747 |
disabled.
|
| 748 |
|
| 749 |
The match_limit number is a measure of the amount of backtracking that
|
| 750 |
takes place, and checking it out can be instructive. For most simple
|
| 751 |
matches, the number is quite small, but for patterns with very large
|
| 752 |
numbers of matching possibilities, it can become large very quickly
|
| 753 |
with increasing length of subject string. The match_limit_recursion
|
| 754 |
number is a measure of how much stack (or, if PCRE is compiled with
|
| 755 |
NO_RECURSE, how much heap) memory is needed to complete the match at-
|
| 756 |
tempt.
|
| 757 |
|
| 758 |
When \O is used, the value specified may be higher or lower than the
|
| 759 |
size set by the -O command line option (or defaulted to 45); \O applies
|
| 760 |
only to the call of pcre[16|32]_exec() for the line in which it ap-
|
| 761 |
pears.
|
| 762 |
|
| 763 |
If the /P modifier was present on the pattern, causing the POSIX wrap-
|
| 764 |
per API to be used, the only option-setting sequences that have any ef-
|
| 765 |
fect are \B, \N, and \Z, causing REG_NOTBOL, REG_NOTEMPTY, and REG_NO-
|
| 766 |
TEOL, respectively, to be passed to regexec().
|
| 767 |
|
| 768 |
|
| 769 |
THE ALTERNATIVE MATCHING FUNCTION
|
| 770 |
|
| 771 |
By default, pcretest uses the standard PCRE matching function,
|
| 772 |
pcre[16|32]_exec() to match each data line. PCRE also supports an al-
|
| 773 |
ternative matching function, pcre[16|32]_dfa_test(), which operates in
|
| 774 |
a different way, and has some restrictions. The differences between the
|
| 775 |
two functions are described in the pcrematching documentation.
|
| 776 |
|
| 777 |
If a data line contains the \D escape sequence, or if the command line
|
| 778 |
contains the -dfa option, the alternative matching function is used.
|
| 779 |
This function finds all possible matches at a given point. If, however,
|
| 780 |
the \F escape sequence is present in the data line, it stops after the
|
| 781 |
first match is found. This is always the shortest possible match.
|
| 782 |
|
| 783 |
|
| 784 |
DEFAULT OUTPUT FROM PCRETEST
|
| 785 |
|
| 786 |
This section describes the output when the normal matching function,
|
| 787 |
pcre[16|32]_exec(), is being used.
|
| 788 |
|
| 789 |
When a match succeeds, pcretest outputs the list of captured substrings
|
| 790 |
that pcre[16|32]_exec() returns, starting with number 0 for the string
|
| 791 |
that matched the whole pattern. Otherwise, it outputs "No match" when
|
| 792 |
the return is PCRE_ERROR_NOMATCH, and "Partial match:" followed by the
|
| 793 |
partially matching substring when pcre[16|32]_exec() returns PCRE_ER-
|
| 794 |
ROR_PARTIAL. (Note that this is the entire substring that was inspected
|
| 795 |
during the partial match; it may include characters before the actual
|
| 796 |
match start if a lookbehind assertion, \K, \b, or \B was involved.) For
|
| 797 |
any other return, pcretest outputs the PCRE negative error number and a
|
| 798 |
short descriptive phrase. If the error is a failed UTF string check,
|
| 799 |
the offset of the start of the failing character and the reason code
|
| 800 |
are also output, provided that the size of the output vector is at
|
| 801 |
least two. Here is an example of an interactive pcretest run.
|
| 802 |
|
| 803 |
$ pcretest
|
| 804 |
PCRE version 8.13 2011-04-30
|
| 805 |
|
| 806 |
re> /^abc(\d+)/
|
| 807 |
data> abc123
|
| 808 |
0: abc123
|
| 809 |
1: 123
|
| 810 |
data> xyz
|
| 811 |
No match
|
| 812 |
|
| 813 |
Unset capturing substrings that are not followed by one that is set are
|
| 814 |
not returned by pcre[16|32]_exec(), and are not shown by pcretest. In
|
| 815 |
the following example, there are two capturing substrings, but when the
|
| 816 |
first data line is matched, the second, unset substring is not shown.
|
| 817 |
An "internal" unset substring is shown as "<unset>", as for the second
|
| 818 |
data line.
|
| 819 |
|
| 820 |
re> /(a)|(b)/
|
| 821 |
data> a
|
| 822 |
0: a
|
| 823 |
1: a
|
| 824 |
data> b
|
| 825 |
0: b
|
| 826 |
1: <unset>
|
| 827 |
2: b
|
| 828 |
|
| 829 |
If the strings contain any non-printing characters, they are output as
|
| 830 |
\xhh escapes if the value is less than 256 and UTF mode is not set.
|
| 831 |
Otherwise they are output as \x{hh...} escapes. See below for the defi-
|
| 832 |
nition of non-printing characters. If the pattern has the /+ modifier,
|
| 833 |
the output for substring 0 is followed by the the rest of the subject
|
| 834 |
string, identified by "0+" like this:
|
| 835 |
|
| 836 |
re> /cat/+
|
| 837 |
data> cataract
|
| 838 |
0: cat
|
| 839 |
0+ aract
|
| 840 |
|
| 841 |
If the pattern has the /g or /G modifier, the results of successive
|
| 842 |
matching attempts are output in sequence, like this:
|
| 843 |
|
| 844 |
re> /\Bi(\w\w)/g
|
| 845 |
data> Mississippi
|
| 846 |
0: iss
|
| 847 |
1: ss
|
| 848 |
0: iss
|
| 849 |
1: ss
|
| 850 |
0: ipp
|
| 851 |
1: pp
|
| 852 |
|
| 853 |
"No match" is output only if the first match attempt fails. Here is an
|
| 854 |
example of a failure message (the offset 4 that is specified by \>4 is
|
| 855 |
past the end of the subject string):
|
| 856 |
|
| 857 |
re> /xyz/
|
| 858 |
data> xyz\>4
|
| 859 |
Error -24 (bad offset value)
|
| 860 |
|
| 861 |
If any of the sequences \C, \G, or \L are present in a data line that
|
| 862 |
is successfully matched, the substrings extracted by the convenience
|
| 863 |
functions are output with C, G, or L after the string number instead of
|
| 864 |
a colon. This is in addition to the normal full list. The string length
|
| 865 |
(that is, the return from the extraction function) is given in paren-
|
| 866 |
theses after each string for \C and \G.
|
| 867 |
|
| 868 |
Note that whereas patterns can be continued over several lines (a plain
|
| 869 |
">" prompt is used for continuations), data lines may not. However new-
|
| 870 |
lines can be included in data by means of the \n escape (or \r, \r\n,
|
| 871 |
etc., depending on the newline sequence setting).
|
| 872 |
|
| 873 |
|
| 874 |
OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION
|
| 875 |
|
| 876 |
When the alternative matching function, pcre[16|32]_dfa_exec(), is used
|
| 877 |
(by means of the \D escape sequence or the -dfa command line option),
|
| 878 |
the output consists of a list of all the matches that start at the
|
| 879 |
first point in the subject where there is at least one match. For exam-
|
| 880 |
ple:
|
| 881 |
|
| 882 |
re> /(tang|tangerine|tan)/
|
| 883 |
data> yellow tangerine\D
|
| 884 |
0: tangerine
|
| 885 |
1: tang
|
| 886 |
2: tan
|
| 887 |
|
| 888 |
(Using the normal matching function on this data finds only "tang".)
|
| 889 |
The longest matching string is always given first (and numbered zero).
|
| 890 |
After a PCRE_ERROR_PARTIAL return, the output is "Partial match:", fol-
|
| 891 |
lowed by the partially matching substring. (Note that this is the en-
|
| 892 |
tire substring that was inspected during the partial match; it may in-
|
| 893 |
clude characters before the actual match start if a lookbehind asser-
|
| 894 |
tion, \K, \b, or \B was involved.)
|
| 895 |
|
| 896 |
If /g is present on the pattern, the search for further matches resumes
|
| 897 |
at the end of the longest match. For example:
|
| 898 |
|
| 899 |
re> /(tang|tangerine|tan)/g
|
| 900 |
data> yellow tangerine and tangy sultana\D
|
| 901 |
0: tangerine
|
| 902 |
1: tang
|
| 903 |
2: tan
|
| 904 |
0: tang
|
| 905 |
1: tan
|
| 906 |
0: tan
|
| 907 |
|
| 908 |
Since the matching function does not support substring capture, the es-
|
| 909 |
cape sequences that are concerned with captured substrings are not rel-
|
| 910 |
evant.
|
| 911 |
|
| 912 |
|
| 913 |
RESTARTING AFTER A PARTIAL MATCH
|
| 914 |
|
| 915 |
When the alternative matching function has given the PCRE_ERROR_PARTIAL
|
| 916 |
return, indicating that the subject partially matched the pattern, you
|
| 917 |
can restart the match with additional subject data by means of the \R
|
| 918 |
escape sequence. For example:
|
| 919 |
|
| 920 |
re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
|
| 921 |
data> 23ja\P\D
|
| 922 |
Partial match: 23ja
|
| 923 |
data> n05\R\D
|
| 924 |
0: n05
|
| 925 |
|
| 926 |
For further information about partial matching, see the pcrepartial
|
| 927 |
documentation.
|
| 928 |
|
| 929 |
|
| 930 |
CALLOUTS
|
| 931 |
|
| 932 |
If the pattern contains any callout requests, pcretest's callout func-
|
| 933 |
tion is called during matching. This works with both matching func-
|
| 934 |
tions. By default, the called function displays the callout number, the
|
| 935 |
start and current positions in the text at the callout time, and the
|
| 936 |
next pattern item to be tested. For example:
|
| 937 |
|
| 938 |
--->pqrabcdef
|
| 939 |
0 ^ ^ \d
|
| 940 |
|
| 941 |
This output indicates that callout number 0 occurred for a match at-
|
| 942 |
tempt starting at the fourth character of the subject string, when the
|
| 943 |
pointer was at the seventh character of the data, and when the next
|
| 944 |
pattern item was \d. Just one circumflex is output if the start and
|
| 945 |
current positions are the same.
|
| 946 |
|
| 947 |
Callouts numbered 255 are assumed to be automatic callouts, inserted as
|
| 948 |
a result of the /C pattern modifier. In this case, instead of showing
|
| 949 |
the callout number, the offset in the pattern, preceded by a plus, is
|
| 950 |
output. For example:
|
| 951 |
|
| 952 |
re> /\d?[A-E]\*/C
|
| 953 |
data> E*
|
| 954 |
--->E*
|
| 955 |
+0 ^ \d?
|
| 956 |
+3 ^ [A-E]
|
| 957 |
+8 ^^ \*
|
| 958 |
+10 ^ ^
|
| 959 |
0: E*
|
| 960 |
|
| 961 |
If a pattern contains (*MARK) items, an additional line is output when-
|
| 962 |
ever a change of latest mark is passed to the callout function. For ex-
|
| 963 |
ample:
|
| 964 |
|
| 965 |
re> /a(*MARK:X)bc/C
|
| 966 |
data> abc
|
| 967 |
--->abc
|
| 968 |
+0 ^ a
|
| 969 |
+1 ^^ (*MARK:X)
|
| 970 |
+10 ^^ b
|
| 971 |
Latest Mark: X
|
| 972 |
+11 ^ ^ c
|
| 973 |
+12 ^ ^
|
| 974 |
0: abc
|
| 975 |
|
| 976 |
The mark changes between matching "a" and "b", but stays the same for
|
| 977 |
the rest of the match, so nothing more is output. If, as a result of
|
| 978 |
backtracking, the mark reverts to being unset, the text "<unset>" is
|
| 979 |
output.
|
| 980 |
|
| 981 |
The callout function in pcretest returns zero (carry on matching) by
|
| 982 |
default, but you can use a \C item in a data line (as described above)
|
| 983 |
to change this and other parameters of the callout.
|
| 984 |
|
| 985 |
Inserting callouts can be helpful when using pcretest to check compli-
|
| 986 |
cated regular expressions. For further information about callouts, see
|
| 987 |
the pcrecallout documentation.
|
| 988 |
|
| 989 |
|
| 990 |
NON-PRINTING CHARACTERS
|
| 991 |
|
| 992 |
When pcretest is outputting text in the compiled version of a pattern,
|
| 993 |
bytes other than 32-126 are always treated as non-printing characters
|
| 994 |
are are therefore shown as hex escapes.
|
| 995 |
|
| 996 |
When pcretest is outputting text that is a matched part of a subject
|
| 997 |
string, it behaves in the same way, unless a different locale has been
|
| 998 |
set for the pattern (using the /L modifier). In this case, the is-
|
| 999 |
print() function to distinguish printing and non-printing characters.
|
| 1000 |
|
| 1001 |
|
| 1002 |
SAVING AND RELOADING COMPILED PATTERNS
|
| 1003 |
|
| 1004 |
The facilities described in this section are not available when the
|
| 1005 |
POSIX interface to PCRE is being used, that is, when the /P pattern
|
| 1006 |
modifier is specified.
|
| 1007 |
|
| 1008 |
When the POSIX interface is not in use, you can cause pcretest to write
|
| 1009 |
a compiled pattern to a file, by following the modifiers with > and a
|
| 1010 |
file name. For example:
|
| 1011 |
|
| 1012 |
/pattern/im >/some/file
|
| 1013 |
|
| 1014 |
See the pcreprecompile documentation for a discussion about saving and
|
| 1015 |
re-using compiled patterns. Note that if the pattern was successfully
|
| 1016 |
studied with JIT optimization, the JIT data cannot be saved.
|
| 1017 |
|
| 1018 |
The data that is written is binary. The first eight bytes are the
|
| 1019 |
length of the compiled pattern data followed by the length of the op-
|
| 1020 |
tional study data, each written as four bytes in big-endian order (most
|
| 1021 |
significant byte first). If there is no study data (either the pattern
|
| 1022 |
was not studied, or studying did not return any data), the second
|
| 1023 |
length is zero. The lengths are followed by an exact copy of the com-
|
| 1024 |
piled pattern. If there is additional study data, this (excluding any
|
| 1025 |
JIT data) follows immediately after the compiled pattern. After writing
|
| 1026 |
the file, pcretest expects to read a new pattern.
|
| 1027 |
|
| 1028 |
A saved pattern can be reloaded into pcretest by specifying < and a
|
| 1029 |
file name instead of a pattern. There must be no space between < and
|
| 1030 |
the file name, which must not contain a < character, as otherwise
|
| 1031 |
pcretest will interpret the line as a pattern delimited by < charac-
|
| 1032 |
ters. For example:
|
| 1033 |
|
| 1034 |
re> </some/file
|
| 1035 |
Compiled pattern loaded from /some/file
|
| 1036 |
No study data
|
| 1037 |
|
| 1038 |
If the pattern was previously studied with the JIT optimization, the
|
| 1039 |
JIT information cannot be saved and restored, and so is lost. When the
|
| 1040 |
pattern has been loaded, pcretest proceeds to read data lines in the
|
| 1041 |
usual way.
|
| 1042 |
|
| 1043 |
You can copy a file written by pcretest to a different host and reload
|
| 1044 |
it there, even if the new host has opposite endianness to the one on
|
| 1045 |
which the pattern was compiled. For example, you can compile on an i86
|
| 1046 |
machine and run on a SPARC machine. When a pattern is reloaded on a
|
| 1047 |
host with different endianness, the confirmation message is changed to:
|
| 1048 |
|
| 1049 |
Compiled pattern (byte-inverted) loaded from /some/file
|
| 1050 |
|
| 1051 |
The test suite contains some saved pre-compiled patterns with different
|
| 1052 |
endianness. These are reloaded using "<!" instead of just "<". This
|
| 1053 |
suppresses the "(byte-inverted)" text so that the output is the same on
|
| 1054 |
all hosts. It also forces debugging output once the pattern has been
|
| 1055 |
reloaded.
|
| 1056 |
|
| 1057 |
File names for saving and reloading can be absolute or relative, but
|
| 1058 |
note that the shell facility of expanding a file name that starts with
|
| 1059 |
a tilde (~) is not available.
|
| 1060 |
|
| 1061 |
The ability to save and reload files in pcretest is intended for test-
|
| 1062 |
ing and experimentation. It is not intended for production use because
|
| 1063 |
only a single pattern can be written to a file. Furthermore, there is
|
| 1064 |
no facility for supplying custom character tables for use with a
|
| 1065 |
reloaded pattern. If the original pattern was compiled with custom ta-
|
| 1066 |
bles, an attempt to match a subject string using a reloaded pattern is
|
| 1067 |
likely to cause pcretest to crash. Finally, if you attempt to load a
|
| 1068 |
file that is not in the correct format, the result is undefined.
|
| 1069 |
|
| 1070 |
|
| 1071 |
SEE ALSO
|
| 1072 |
|
| 1073 |
pcre(3), pcre16(3), pcre32(3), pcreapi(3), pcrecallout(3), pcrejit,
|
| 1074 |
pcrematching(3), pcrepartial(d), pcrepattern(3), pcreprecompile(3).
|
| 1075 |
|
| 1076 |
|
| 1077 |
AUTHOR
|
| 1078 |
|
| 1079 |
Philip Hazel
|
| 1080 |
University Computing Service
|
| 1081 |
Cambridge CB2 3QH, England.
|
| 1082 |
|
| 1083 |
|
| 1084 |
REVISION
|
| 1085 |
|
| 1086 |
Last updated: 10 February 2020
|
| 1087 |
Copyright (c) 1997-2020 University of Cambridge.
|
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| 
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