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@@ -1,319 +1,450 @@
-NAME
- pcretest - a program for testing Perl-compatible regular
- expressions.
+PCRETEST(1) PCRETEST(1)
+
+NAME
+ pcretest - a program for testing Perl-compatible regular expressions.
SYNOPSIS
- pcretest [-d] [-i] [-m] [-o osize] [-p] [-t] [source] [des-
- tination]
- pcretest was written as a test program for the PCRE regular
- expression library itself, but it can also be used for
- experimenting with regular expressions. This man page
- describes the features of the test program; for details of
- the regular expressions themselves, see the pcre man page.
+ pcretest [-C] [-d] [-i] [-m] [-o osize] [-p] [-t] [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
+ expressions. This document describes the features of the test program;
+ for details of the regular expressions themselves, see the pcrepattern
+ documentation. For details of the PCRE library function calls and their
+ options, see the pcreapi documentation.
OPTIONS
- -d Behave as if each regex had the /D modifier (see
- below); the internal form is output after compila-
- tion.
-
- -i Behave as if each regex had the /I modifier;
- information about the compiled pattern is given
- after compilation.
-
- -m Output the size of each compiled pattern after it
- has been compiled. This is equivalent to adding /M
- to each regular expression. For compatibility with
- earlier versions of pcretest, -s is a synonym for
- -m.
-
- -o osize Set the number of elements in the output vector
- that is used when calling PCRE to be osize. The
- default value is 45, which is enough for 14 cap-
- turing subexpressions. The vector size can be
- changed for individual matching calls by including
- \O in the data line (see below).
- -p Behave as if each regex has /P modifier; the POSIX
- wrapper API is used to call PCRE. None of the
- other options has any effect when -p is set.
+ -C Output the version number of the PCRE library, and all avail-
+ able information about the optional features that are
+ included, and then exit.
- -t Run each compile, study, and match 20000 times
- with a timer, and output resulting time per com-
- pile or match (in milliseconds). Do not set -t
- with -m, because you will then get the size output
- 20000 times and the timing will be distorted.
+ -d Behave as if each regex had the /D (debug) modifier; the
+ internal form is output after compilation.
+ -i Behave as if each regex had the /I modifier; information
+ about the compiled pattern is given after compilation.
+ -m Output the size of each compiled pattern after it has been
+ compiled. This is equivalent to adding /M to each regular
+ expression. For compatibility with earlier versions of
+ pcretest, -s is a synonym for -m.
-DESCRIPTION
- If pcretest is given two filename arguments, it reads from
- the first and writes to the second. If it is given only one
-
+ -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).
+ -p Behave as if each regex has /P modifier; the POSIX wrapper
+ API is used to call PCRE. None of the other options has any
+ effect when -p is set.
+ -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.
-SunOS 5.8 Last change: 1
+DESCRIPTION
+ If pcretest is given two filename arguments, it reads from the first
+ and writes to the second. If it is given only one filename argument, it
+ reads from that file and writes to stdout. Otherwise, it reads from
+ stdin and writes to stdout, and prompts for each line of input, using
+ "re>" to prompt for regular expressions, and "data>" to prompt for data
+ lines.
- filename argument, it reads from that file and writes to
- stdout. Otherwise, it reads from stdin and writes to stdout,
- and prompts for each line of input, using "re>" to prompt
- for regular expressions, and "data>" to prompt for data
- lines.
+ The program handles any number of sets of input on a single input file.
+ Each set starts with a regular expression, and continues with any num-
+ ber of data lines to be matched against the pattern.
- The program handles any number of sets of input on a single
- input file. Each set starts with a regular expression, and
- continues with any number of data lines to be matched
- against the pattern. 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-
- alphameric delimiters other than backslash, for example
+ 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.
- /(a|bc)x+yz/
+ 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
- White space before the initial delimiter is ignored. A regu-
- lar expression may be continued over several input lines, in
- which case the newline characters are included within it. It
- is possible to include the delimiter within the pattern by
- escaping it, for example
+ /(a|bc)x+yz/
- /abc\/def/
+ White space before the initial delimiter is ignored. A regular expres-
+ sion may be continued over several input lines, in which case the new-
+ line characters are included within it. It is possible to include the
+ delimiter within the pattern by escaping it, for example
- If you do so, the escape and the delimiter form part of the
- pattern, but since delimiters are always non-alphameric,
- this does not affect its interpretation. If the terminating
- delimiter is immediately followed by a backslash, for exam-
- ple,
+ /abc\/def/
- /abc/\
+ If you do so, the escape and the delimiter form part of the pattern,
+ but since delimiters are always non-alphanumeric, this does not affect
+ its interpretation. If the terminating delimiter is immediately fol-
+ lowed by a backslash, for example,
- then a backslash is added to the end of the pattern. This is
- done to provide a way of testing the error condition that
- arises if a pattern finishes with a backslash, because
+ /abc/\
- /abc\/
+ then a backslash is added to the end of the pattern. This is done to
+ provide a way of testing the error condition that arises if a pattern
+ finishes with a backslash, because
- is interpreted as the first line of a pattern that starts
- with "abc/", causing pcretest to read the next line as a
- continuation of the regular expression.
+ /abc\/
+ is interpreted as the first line of a pattern that starts with "abc/",
+ causing pcretest to read the next line as a continuation of the regular
+ expression.
PATTERN MODIFIERS
- The pattern may be followed by i, m, s, or x to set the
- PCRE_CASELESS, PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED
- options, respectively. For example:
-
- /caseless/i
-
- These modifier letters have the same effect as they do in
- Perl. There are others which set PCRE options that do not
- correspond to anything in Perl: /A, /E, and /X set
- PCRE_ANCHORED, PCRE_DOLLAR_ENDONLY, and PCRE_EXTRA respec-
- tively.
-
- 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 difference 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 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 handles such
- cases when using the /g modifier or the split() function.
-
- There are a number of other modifiers for controlling the
- way pcretest operates.
-
- The /+ modifier requests that as well as outputting the sub-
- string 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 /L modifier must be followed directly by the name of a
- locale, for example,
-
- /pattern/Lfr
-
- For this reason, it must be the last modifier letter. The
- given locale is set, pcre_maketables() is called to build a
- set of character tables for the locale, and this is then
- passed to pcre_compile() when compiling the regular expres-
- sion. Without an /L modifier, NULL is passed as the tables
- pointer; that is, /L applies only to the expression on which
- it appears.
-
- The /I modifier requests that pcretest output information
- about the compiled expression (whether it is anchored, has a
- fixed first character, and so on). It does this by calling
- pcre_fullinfo() after compiling an expression, and output-
- ting the information it gets back. If the pattern is stu-
- died, the results of that are also output.
- 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.
-
- The /S modifier causes pcre_study() to be called after the
- expression has been compiled, and the results used when the
- expression is matched.
-
- The /M modifier causes the size of memory block used to hold
- the compiled pattern to be output.
-
- The /P modifier causes pcretest to call PCRE via the POSIX
- wrapper API rather than its native API. When this is done,
- all other modifiers except /i, /m, and /+ are ignored.
- REG_ICASE is set if /i is present, and REG_NEWLINE is set if
- /m is present. The wrapper functions force
- PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless
- REG_NEWLINE is set.
-
- The /8 modifier causes pcretest to call PCRE with the
- PCRE_UTF8 option set. This turns on the (currently incom-
- plete) support for UTF-8 character handling in PCRE, pro-
- vided that it was compiled with this support enabled. This
- modifier also causes any non-printing characters in output
- strings to be printed using the \x{hh...} notation if they
- are valid UTF-8 sequences.
+ A pattern may be followed by any number of modifiers, which are mostly
+ single characters. Following Perl usage, these are referred to below
+ as, for example, "the /i modifier", even though the delimiter of the
+ pattern need not always be a slash, and no slash is used when writing
+ modifiers. Whitespace may appear between the final pattern delimiter
+ and the first modifier, and between the modifiers themselves.
+
+ The /i, /m, /s, and /x modifiers set the PCRE_CASELESS, PCRE_MULTILINE,
+ PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when pcre_com-
+ pile() is called. These four modifier letters have the same effect as
+ they do in Perl. For example:
+
+ /caseless/i
+
+ 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
+ /N PCRE_NO_AUTO_CAPTURE
+ /U PCRE_UNGREEDY
+ /X PCRE_EXTRA
+
+ 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
+ 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-
+ dles such cases when using the /g modifier or the split() function.
+
+ 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
+ subject contains multiple copies of the same substring.
+
+ The /L modifier must be followed directly by the name of a locale, for
+ example,
+
+ /pattern/Lfr_FR
+
+ For this reason, it must be the last modifier. The given locale is set,
+ pcre_maketables() is called to build a set of character tables for the
+ locale, and this is then passed to pcre_compile() when compiling the
+ regular expression. Without an /L modifier, NULL is passed as the
+ tables pointer; that is, /L applies only to the expression on which it
+ appears.
+
+ The /I modifier requests that pcretest output information about the
+ compiled pattern (whether it is anchored, has a fixed first character,
+ and so on). It does this by calling pcre_fullinfo() after compiling a
+ 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 /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
+ facility is for testing the feature in PCRE that allows it to execute
+ patterns that were compiled on a host with a different endianness. This
+ feature is not available when the POSIX interface to PCRE is being
+ used, that is, when the /P pattern modifier is specified. See also the
+ section about saving and reloading compiled patterns below.
+
+ The /S modifier causes pcre_study() to be called after the expression
+ has been compiled, and the results used when the expression is matched.
+
+ The /M modifier causes the size of memory block used to hold the com-
+ piled pattern to be output.
+
+ The /P modifier causes pcretest to call PCRE via the POSIX wrapper API
+ rather than its native API. When this is done, all other modifiers
+ except /i, /m, and /+ are ignored. REG_ICASE is set if /i is present,
+ and REG_NEWLINE is set if /m is present. The wrapper functions force
+ PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless REG_NEWLINE is set.
+
+ The /8 modifier causes pcretest to call PCRE with the PCRE_UTF8 option
+ set. This turns on support for UTF-8 character handling in PCRE, pro-
+ vided that it was compiled with this support enabled. This modifier
+ also causes any non-printing characters in output strings to be printed
+ using the \x{hh...} notation if they are valid UTF-8 sequences.
+
+ If the /? modifier is used with /8, it causes pcretest to call
+ pcre_compile() with the PCRE_NO_UTF8_CHECK option, to suppress the
+ checking of the string for UTF-8 validity.
DATA LINES
- Before each data line is passed to pcre_exec(), leading and
- trailing whitespace is removed, and it is then scanned for \
- escapes. The following are recognized:
-
- \a alarm (= BEL)
- \b backspace
- \e escape
- \f formfeed
- \n newline
- \r carriage return
- \t tab
- \v vertical tab
- \nnn octal character (up to 3 octal digits)
- \xhh hexadecimal character (up to 2 hex digits)
- \x{hh...} hexadecimal UTF-8 character
-
- \A pass the PCRE_ANCHORED option to pcre_exec()
- \B pass the PCRE_NOTBOL option to pcre_exec()
- \Cdd call pcre_copy_substring() for substring dd
- after a successful match (any decimal number
- less than 32)
- \Gdd call pcre_get_substring() for substring dd
-
- after a successful match (any decimal number
- less than 32)
- \L call pcre_get_substringlist() after a
- successful match
- \N pass the PCRE_NOTEMPTY option to pcre_exec()
- \Odd set the size of the output vector passed to
- pcre_exec() to dd (any number of decimal
- digits)
- \Z pass the PCRE_NOTEOL option to pcre_exec()
-
- When \O is used, it may be higher or lower than the size set
- by the -O option (or defaulted to 45); \O applies only to
- the call of pcre_exec() for the line in which it appears.
-
- A backslash followed by anything else just escapes the any-
- thing else. If the very last character is a backslash, it is
- ignored. This gives a way of passing an empty line as data,
- since a real empty line terminates the data input.
-
- If /P was present on the regex, causing the POSIX wrapper
- API to be used, only B, and Z have any effect, causing
- REG_NOTBOL and REG_NOTEOL to be passed to regexec() respec-
- tively.
-
- 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. There may be any number of hexadecimal
- digits inside the braces. The result is from one to six
- bytes, encoded according to the UTF-8 rules.
+ Before each data line is passed to pcre_exec(), leading and trailing
+ whitespace is removed, and it is then scanned for \ escapes. Some of
+ these are pretty esoteric features, intended for checking out some of
+ the more complicated features of PCRE. If you are just testing "ordi-
+ 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
+ \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()
+ \B pass the PCRE_NOTBOL option to pcre_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
+ "name" after a successful match (name termin-
+ ated by next non alphanumeric character)
+ \C+ show the current captured substrings at callout
+ time
+ \C- do not supply a callout function
+ \C!n return 1 instead of 0 when callout number n is
+ reached
+ \C!n!m return 1 instead of 0 when callout number n is
+ reached for the nth time
+ \C*n pass the number n (may be negative) as callout
+ data; this is used as the callout return value
+ \Gdd call pcre_get_substring() for substring dd
+ after a successful match (number less than 32)
+ \Gname call pcre_get_named_substring() for substring
+ "name" after a successful match (name termin-
+ ated by next non-alphanumeric character)
+ \L call pcre_get_substringlist() after a
+ successful match
+ \M discover the minimum MATCH_LIMIT setting
+ \N pass the PCRE_NOTEMPTY option to pcre_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()
+ \S output details of memory get/free calls during matching
+ \Z pass the PCRE_NOTEOL option to pcre_exec()
+ \? pass the PCRE_NO_UTF8_CHECK option to
+ pcre_exec()
+ \>dd start the match at offset dd (any number of digits);
+ this sets the startoffset argument for pcre_exec()
+
+ 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
+ way of passing an empty line as data, since a real empty line termi-
+ 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
+ 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.
+
+ 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.
+ There may be any number of hexadecimal digits inside the braces. The
+ result is from one to six bytes, encoded according to the UTF-8 rules.
OUTPUT FROM PCRETEST
- When a match succeeds, pcretest outputs the list of captured
- substrings that pcre_exec() returns, starting with number 0
- for the string that matched the whole pattern. Here is an
- example of an interactive pcretest run.
-
- $ pcretest
- PCRE version 2.06 08-Jun-1999
-
- re> /^abc(\d+)/
- data> abc123
- 0: abc123
- 1: 123
- data> xyz
- No match
-
- 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, then the output for substring 0 is followed 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 matching attempts are output in sequence, like
- this:
-
- re> /\Bi(\w\w)/g
- data> Mississippi
- 0: iss
- 1: ss
- 0: iss
- 1: ss
- 0: ipp
- 1: pp
-
- "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 functions are output with C, G, or L
- after the string number instead of a colon. This is in addi-
- tion to the normal full list. The string length (that is,
- the return from the extraction function) is given in
- parentheses after each string for \C and \G.
-
- Note that while patterns can be continued over several lines
- (a plain ">" prompt is used for continuations), data lines
- may not. However newlines can be included in data by means
- of the \n escape.
+ When a match succeeds, pcretest outputs the list of captured substrings
+ that pcre_exec() returns, starting with number 0 for the string that
+ matched the whole pattern. Otherwise, it outputs "No match" or "Partial
+ match" when pcre_exec() returns PCRE_ERROR_NOMATCH or PCRE_ERROR_PAR-
+ TIAL, respectively, and otherwise the PCRE negative error number. Here
+ is an example of an interactive pcretest run.
+
+ $ pcretest
+ PCRE version 5.00 07-Sep-2004
+
+ re> /^abc(\d+)/
+ data> abc123
+ 0: abc123
+ 1: 123
+ data> xyz
+ No match
+
+ 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:
+
+ re> /cat/+
+ data> cataract
+ 0: cat
+ 0+ aract
+
+ 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
+ data> Mississippi
+ 0: iss
+ 1: ss
+ 0: iss
+ 1: ss
+ 0: ipp
+ 1: pp
+
+ "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
+ 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-
+ theses after each string for \C and \G.
+
+ Note that while 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.
+
+
+CALLOUTS
+
+ If the pattern contains any callout requests, pcretest's callout func-
+ tion is called during matching. By default, it displays the callout
+ number, the start and current positions in the text at the callout
+ time, and the next pattern item to be tested. For example, the output
+
+ --->pqrabcdef
+ 0 ^ ^ \d
+
+ indicates that callout number 0 occurred for a match attempt starting
+ at the fourth character of the subject string, when the pointer was at
+ the seventh character of the data, and when the next pattern item was
+ \d. Just one circumflex is output if the start and current positions
+ are the same.
+
+ Callouts numbered 255 are assumed to be automatic callouts, inserted as
+ a result of the /C pattern modifier. In this case, instead of showing
+ the callout number, the offset in the pattern, preceded by a plus, is
+ output. For example:
+
+ re> /\d?[A-E]\*/C
+ data> E*
+ --->E*
+ +0 ^ \d?
+ +3 ^ [A-E]
+ +8 ^^ \*
+ +10 ^ ^
+ 0: E*
+
+ The callout function in pcretest returns zero (carry on matching) by
+ default, but you can use an \C item in a data line (as described above)
+ to change this.
+
+ Inserting callouts can be helpful when using pcretest to check compli-
+ cated regular expressions. For further information about callouts, see
+ the pcrecallout documentation.
+
+
+SAVING AND RELOADING COMPILED PATTERNS
+
+ The facilities described in this section are not available when the
+ POSIX inteface to PCRE is being used, that is, when the /P pattern mod-
+ ifier is specified.
+
+ When the POSIX interface is not in use, you can cause pcretest to write
+ a compiled pattern to a file, by following the modifiers with > and a
+ file name. For example:
+
+ /pattern/im >/some/file
+
+ See the pcreprecompile documentation for a discussion about saving and
+ re-using compiled patterns.
+
+ The data that is written is binary. The first eight bytes are the
+ length of the compiled pattern data followed by the length of the
+ optional study data, each written as four bytes in big-endian order
+ (most significant byte first). If there is no study data (either the
+ pattern was not studied, or studying did not return any data), the sec-
+ ond length is zero. The lengths are followed by an exact copy of the
+ compiled pattern. If there is additional study data, this follows imme-
+ diately after the compiled pattern. After writing the file, pcretest
+ expects to read a new pattern.
+
+ A saved pattern can be reloaded into pcretest by specifing < and a file
+ name instead of a pattern. The name of the file must not contain a <
+ character, as otherwise pcretest will interpret the line as a pattern
+ delimited by < characters. For example:
+
+ re> </some/file
+ Compiled regex loaded from /some/file
+ No study data
+
+ When the pattern has been loaded, pcretest proceeds to read data lines
+ in the usual way.
+
+ You can copy a file written by pcretest to a different host and reload
+ it there, even if the new host has opposite endianness to the one on
+ which the pattern was compiled. For example, you can compile on an i86
+ machine and run on a SPARC machine.
+
+ File names for saving and reloading can be absolute or relative, but
+ note that the shell facility of expanding a file name that starts with
+ a tilde (~) is not available.
+
+ The ability to save and reload files in pcretest is intended for test-
+ ing and experimentation. It is not intended for production use because
+ only a single pattern can be written to a file. Furthermore, there is
+ no facility for supplying custom character tables for use with a
+ reloaded pattern. If the original pattern was compiled with custom
+ tables, an attempt to match a subject string using a reloaded pattern
+ is likely to cause pcretest to crash. Finally, if you attempt to load
+ a file that is not in the correct format, the result is undefined.
AUTHOR
- Philip Hazel <ph10@cam.ac.uk>
- University Computing Service,
- New Museums Site,
- Cambridge CB2 3QG, England.
- Phone: +44 1223 334714
-
- Last updated: 15 August 2001
- Copyright (c) 1997-2001 University of Cambridge.
+
+ Philip Hazel <ph10@cam.ac.uk>
+ University Computing Service,
+ Cambridge CB2 3QG, England.
+
+Last updated: 10 September 2004
+Copyright (c) 1997-2004 University of Cambridge.