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diff --git a/pcre/doc/pcretest.txt b/pcre/doc/pcretest.txt deleted file mode 100644 index 6d7305cfe82..00000000000 --- a/pcre/doc/pcretest.txt +++ /dev/null @@ -1,1091 +0,0 @@ -PCRETEST(1) General Commands Manual PCRETEST(1) - - - -NAME - pcretest - a program for testing Perl-compatible regular expressions. - -SYNOPSIS - - pcretest [options] [input file [output file]] - - 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 , pcre16 and pcre32 documentation. - - The input for pcretest is a sequence of regular expression patterns and - strings to be matched, as described below. The output shows the result - of each match. Options on the command line and the patterns control - PCRE options and exactly what is output. - - As PCRE has evolved, it has acquired many different features, and as a - result, pcretest now has rather a lot of obscure options for testing - every possible feature. Some of these options are specifically designed - for use in conjunction with the test script and data files that are - distributed as part of PCRE, and are unlikely to be of use otherwise. - They are all documented here, but without much justification. - - -INPUT DATA FORMAT - - Input to pcretest is processed line by line, either by calling the C - library's fgets() function, or via the libreadline library (see below). - In Unix-like environments, fgets() treats any bytes other than newline - as data characters. However, in some Windows environments character 26 - (hex 1A) causes an immediate end of file, and no further data is read. - For maximum portability, therefore, it is safest to use only ASCII - characters in pcretest input files. - - The input is processed using using C's string functions, so must not - contain binary zeroes, even though in Unix-like environments, fgets() - treats any bytes other than newline as data characters. - - -PCRE's 8-BIT, 16-BIT AND 32-BIT LIBRARIES - - From release 8.30, two separate PCRE libraries can be built. The origi- - nal one supports 8-bit character strings, whereas the newer 16-bit - library supports character strings encoded in 16-bit units. From - release 8.32, a third library can be built, supporting character - strings encoded in 32-bit units. The pcretest program can be used to - test all three libraries. However, it is itself still an 8-bit program, - reading 8-bit input and writing 8-bit output. When testing the 16-bit - or 32-bit library, the patterns and data strings are converted to 16- - or 32-bit format before being passed to the PCRE library functions. - Results are converted to 8-bit for output. - - References to functions and structures of the form pcre[16|32]_xx below - mean "pcre_xx when using the 8-bit library, pcre16_xx when using the - 16-bit library, or pcre32_xx when using the 32-bit library". - - -COMMAND LINE OPTIONS - - -8 If both the 8-bit library has been built, this option causes - the 8-bit library to be used (which is the default); if the - 8-bit library has not been built, this option causes an - error. - - -16 If both the 8-bit or the 32-bit, and the 16-bit libraries - have been built, this option causes the 16-bit library to be - used. If only the 16-bit library has been built, this is the - default (so has no effect). If only the 8-bit or the 32-bit - library has been built, this option causes an error. - - -32 If both the 8-bit or the 16-bit, and the 32-bit libraries - have been built, this option causes the 32-bit library to be - used. If only the 32-bit library has been built, this is the - default (so has no effect). If only the 8-bit or the 16-bit - library has been built, this option causes an error. - - -b Behave as if each pattern has the /B (show byte code) modi- - fier; the internal form is output after compilation. - - -C Output the version number of the PCRE library, and all avail- - able information about the optional features that are - included, and then exit with zero exit code. All other - options are ignored. - - -C option Output information about a specific build-time option, then - exit. This functionality is intended for use in scripts such - as RunTest. The following options output the value and set - the exit code as indicated: - - ebcdic-nl the code for LF (= NL) in an EBCDIC environment: - 0x15 or 0x25 - 0 if used in an ASCII environment - exit code is always 0 - linksize the configured internal link size (2, 3, or 4) - exit code is set to the link size - newline the default newline setting: - CR, LF, CRLF, ANYCRLF, or ANY - exit code is always 0 - bsr the default setting for what \R matches: - ANYCRLF or ANY - exit code is always 0 - - The following options output 1 for true or 0 for false, and - set the exit code to the same value: - - ebcdic compiled for an EBCDIC environment - jit just-in-time support is available - pcre16 the 16-bit library was built - pcre32 the 32-bit library was built - pcre8 the 8-bit library was built - ucp Unicode property support is available - utf UTF-8 and/or UTF-16 and/or UTF-32 support - is available - - If an unknown option is given, an error message is output; - the exit code is 0. - - -d Behave as if each pattern has the /D (debug) modifier; the - internal form and information about the compiled pattern is - output after compilation; -d is equivalent to -b -i. - - -dfa Behave as if each data line contains the \D escape sequence; - this causes the alternative matching function, - pcre[16|32]_dfa_exec(), to be used instead of the standard - pcre[16|32]_exec() function (more detail is given below). - - -help Output a brief summary these options and then exit. - - -i Behave as if each pattern has the /I modifier; information - about the compiled pattern is given after compilation. - - -M Behave as if each data line contains the \M escape sequence; - this causes PCRE to discover the minimum MATCH_LIMIT and - MATCH_LIMIT_RECURSION settings by calling pcre[16|32]_exec() - repeatedly with different limits. - - -m Output the size of each compiled pattern after it has been - compiled. This is equivalent to adding /M to each regular - expression. The size is given in bytes for both libraries. - - -O Behave as if each pattern has the /O modifier, that is dis- - able auto-possessification for all patterns. - - -o osize Set the number of elements in the output vector that is used - when calling pcre[16|32]_exec() or pcre[16|32]_dfa_exec() to - be osize. The default value is 45, which is enough for 14 - capturing subexpressions for pcre[16|32]_exec() or 22 differ- - ent matches for pcre[16|32]_dfa_exec(). The vector size can - be changed for individual matching calls by including \O in - the data line (see below). - - -p Behave as if each pattern has the /P modifier; the POSIX - wrapper API is used to call PCRE. None of the other options - has any effect when -p is set. This option can be used only - with the 8-bit library. - - -q Do not output the version number of pcretest at the start of - execution. - - -S size On Unix-like systems, set the size of the run-time stack to - size megabytes. - - -s or -s+ Behave as if each pattern has the /S modifier; in other - words, force each pattern to be studied. If -s+ is used, all - the JIT compile options are passed to pcre[16|32]_study(), - causing just-in-time optimization to be set up if it is - available, for both full and partial matching. Specific JIT - compile options can be selected by following -s+ with a digit - in the range 1 to 7, which selects the JIT compile modes as - follows: - - 1 normal match only - 2 soft partial match only - 3 normal match and soft partial match - 4 hard partial match only - 6 soft and hard partial match - 7 all three modes (default) - - If -s++ is used instead of -s+ (with or without a following - digit), the text "(JIT)" is added to the first output line - after a match or no match when JIT-compiled code was actually - used. - - Note that there are pattern options that can override -s, - either specifying no studying at all, or suppressing JIT com- - pilation. - - If the /I or /D option is present on a pattern (requesting - output about the compiled pattern), information about the - result of studying is not included when studying is caused - only by -s and neither -i nor -d is present on the command - line. This behaviour means that the output from tests that - are run with and without -s should be identical, except when - options that output information about the actual running of a - match are set. - - The -M, -t, and -tm options, which give information about - resources used, are likely to produce different output with - and without -s. Output may also differ if the /C option is - present on an individual pattern. This uses callouts to trace - the the matching process, and this may be different between - studied and non-studied patterns. If the pattern contains - (*MARK) items there may also be differences, for the same - reason. The -s command line option can be overridden for spe- - cific patterns that should never be studied (see the /S pat- - tern modifier below). - - -t Run each compile, study, and match many times with a timer, - and output the resulting times per compile, study, or match - (in milliseconds). Do not set -m with -t, because you will - then get the size output a zillion times, and the timing will - be distorted. You can control the number of iterations that - are used for timing by following -t with a number (as a sepa- - rate item on the command line). For example, "-t 1000" iter- - ates 1000 times. The default is to iterate 500000 times. - - -tm This is like -t except that it times only the matching phase, - not the compile or study phases. - - -T -TM These behave like -t and -tm, but in addition, at the end of - a run, the total times for all compiles, studies, and matches - are output. - - -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. - - When pcretest is built, a configuration option can specify that it - should be linked with the libreadline library. When this is done, if - the input is from a terminal, it is read using the readline() function. - This provides line-editing and history facilities. The output from the - -help option states whether or not readline() will be used. - - 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 that pattern. - - Each data line is matched separately and independently. If you want to - do multi-line matches, you have to use the \n escape sequence (or \r or - \r\n, etc., depending on the newline setting) in a single line of input - to encode the newline sequences. There is no limit on the length of - data lines; the input buffer is automatically extended if it is too - small. - - An empty line signals the end of the data lines, at which point a new - regular expression is read. The regular expressions are given enclosed - in any non-alphanumeric delimiters other than backslash, for example: - - /(a|bc)x+yz/ - - 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 - - /abc\/def/ - - 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, - - /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 - - /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 - - A pattern may be followed by any number of modifiers, which are mostly - single characters, though some of these can be qualified by further - 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 modi- - fiers. White space may appear between the final pattern delimiter and - the first modifier, and between the modifiers themselves. For refer- - ence, here is a complete list of modifiers. They fall into several - groups that are described in detail in the following sections. - - /8 set UTF mode - /9 set PCRE_NEVER_UTF (locks out UTF mode) - /? disable UTF validity check - /+ show remainder of subject after match - /= show all captures (not just those that are set) - - /A set PCRE_ANCHORED - /B show compiled code - /C set PCRE_AUTO_CALLOUT - /D same as /B plus /I - /E set PCRE_DOLLAR_ENDONLY - /F flip byte order in compiled pattern - /f set PCRE_FIRSTLINE - /G find all matches (shorten string) - /g find all matches (use startoffset) - /I show information about pattern - /i set PCRE_CASELESS - /J set PCRE_DUPNAMES - /K show backtracking control names - /L set locale - /M show compiled memory size - /m set PCRE_MULTILINE - /N set PCRE_NO_AUTO_CAPTURE - /O set PCRE_NO_AUTO_POSSESS - /P use the POSIX wrapper - /Q test external stack check function - /S study the pattern after compilation - /s set PCRE_DOTALL - /T select character tables - /U set PCRE_UNGREEDY - /W set PCRE_UCP - /X set PCRE_EXTRA - /x set PCRE_EXTENDED - /Y set PCRE_NO_START_OPTIMIZE - /Z don't show lengths in /B output - - /<any> set PCRE_NEWLINE_ANY - /<anycrlf> set PCRE_NEWLINE_ANYCRLF - /<cr> set PCRE_NEWLINE_CR - /<crlf> set PCRE_NEWLINE_CRLF - /<lf> set PCRE_NEWLINE_LF - /<bsr_anycrlf> set PCRE_BSR_ANYCRLF - /<bsr_unicode> set PCRE_BSR_UNICODE - /<JS> set PCRE_JAVASCRIPT_COMPAT - - - Perl-compatible modifiers - - The /i, /m, /s, and /x modifiers set the PCRE_CASELESS, PCRE_MULTILINE, - PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when - pcre[16|32]_compile() is called. These four modifier letters have the - same effect as they do in Perl. For example: - - /caseless/i - - - Modifiers for other PCRE options - - The following table shows additional modifiers for setting PCRE com- - pile-time options that do not correspond to anything in Perl: - - /8 PCRE_UTF8 ) when using the 8-bit - /? PCRE_NO_UTF8_CHECK ) library - - /8 PCRE_UTF16 ) when using the 16-bit - /? PCRE_NO_UTF16_CHECK ) library - - /8 PCRE_UTF32 ) when using the 32-bit - /? PCRE_NO_UTF32_CHECK ) library - - /9 PCRE_NEVER_UTF - /A PCRE_ANCHORED - /C PCRE_AUTO_CALLOUT - /E PCRE_DOLLAR_ENDONLY - /f PCRE_FIRSTLINE - /J PCRE_DUPNAMES - /N PCRE_NO_AUTO_CAPTURE - /O PCRE_NO_AUTO_POSSESS - /U PCRE_UNGREEDY - /W PCRE_UCP - /X PCRE_EXTRA - /Y PCRE_NO_START_OPTIMIZE - /<any> PCRE_NEWLINE_ANY - /<anycrlf> PCRE_NEWLINE_ANYCRLF - /<cr> PCRE_NEWLINE_CR - /<crlf> PCRE_NEWLINE_CRLF - /<lf> PCRE_NEWLINE_LF - /<bsr_anycrlf> PCRE_BSR_ANYCRLF - /<bsr_unicode> PCRE_BSR_UNICODE - /<JS> PCRE_JAVASCRIPT_COMPAT - - The modifiers that are enclosed in angle brackets are literal strings - as shown, including the angle brackets, but the letters within can be - in either case. This example sets multiline matching with CRLF as the - line ending sequence: - - /^abc/m<CRLF> - - As well as turning on the PCRE_UTF8/16/32 option, the /8 modifier - causes all non-printing characters in output strings to be printed - using the \x{hh...} notation. Otherwise, those less than 0x100 are out- - put in hex without the curly brackets. - - Full details of the PCRE options are given in the pcreapi documenta- - tion. - - Finding all matches in a string - - Searching for all possible matches within each subject string can be - requested by the /g or /G modifier. After finding a match, PCRE is - 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[16|32]_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[16|32]_exec() in a /g or /G sequence matches an - empty string, the next call is done with the PCRE_NOTEMPTY_ATSTART 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, and the normal match is retried. This imitates the way - Perl handles such cases when using the /g modifier or the split() func- - tion. Normally, the start offset is advanced by one character, but if - the newline convention recognizes CRLF as a newline, and the current - character is CR followed by LF, an advance of two is used. - - Other modifiers - - There are yet more modifiers for controlling the way pcretest operates. - - The /+ modifier requests that as well as outputting the substring that - matched the entire pattern, pcretest should in addition output the - remainder of the subject string. This is useful for tests where the - subject contains multiple copies of the same substring. If the + modi- - fier appears twice, the same action is taken for captured substrings. - In each case the remainder is output on the following line with a plus - character following the capture number. Note that this modifier must - not immediately follow the /S modifier because /S+ and /S++ have other - meanings. - - The /= modifier requests that the values of all potential captured - parentheses be output after a match. By default, only those up to the - highest one actually used in the match are output (corresponding to the - return code from pcre[16|32]_exec()). Values in the offsets vector cor- - responding to higher numbers should be set to -1, and these are output - as "<unset>". This modifier gives a way of checking that this is hap- - pening. - - The /B modifier is a debugging feature. It requests that pcretest out- - put a representation of the compiled code after compilation. Normally - this information contains length and offset values; however, if /Z is - also present, this data is replaced by spaces. This is a special fea- - ture for use in the automatic test scripts; it ensures that the same - output is generated for different internal link sizes. - - The /D modifier is a PCRE debugging feature, and is equivalent to /BI, - that is, both the /B and the /I modifiers. - - The /F modifier causes pcretest to flip the byte order of the 2-byte - and 4-byte fields in the compiled pattern. This facility is for testing - the feature in PCRE that allows it to execute patterns that were com- - piled on a host with a different endianness. This feature is not avail- - able 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 /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[16|32]_fullinfo() after com- - piling a pattern. If the pattern is studied, the results of that are - also output. In this output, the word "char" means a non-UTF character, - that is, the value of a single data item (8-bit, 16-bit, or 32-bit, - depending on the library that is being tested). - - The /K modifier requests pcretest to show names from backtracking con- - trol verbs that are returned from calls to pcre[16|32]_exec(). It - causes pcretest to create a pcre[16|32]_extra block if one has not - already been created by a call to pcre[16|32]_study(), and to set the - PCRE_EXTRA_MARK flag and the mark field within it, every time that - pcre[16|32]_exec() is called. If the variable that the mark field - points to is non-NULL for a match, non-match, or partial match, - pcretest prints the string to which it points. For a match, this is - shown on a line by itself, tagged with "MK:". For a non-match it is - added to the message. - - 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[16|32]_maketables() is called to build a set of character tables - for the locale, and this is then passed to pcre[16|32]_compile() when - compiling the regular expression. Without an /L (or /T) modifier, NULL - is passed as the tables pointer; that is, /L applies only to the - expression on which it appears. - - The /M modifier causes the size in bytes of the memory block used to - hold the compiled pattern to be output. This does not include the size - of the pcre[16|32] block; it is just the actual compiled data. If the - pattern is successfully studied with the PCRE_STUDY_JIT_COMPILE option, - the size of the JIT compiled code is also output. - - The /Q modifier is used to test the use of pcre_stack_guard. It must be - followed by '0' or '1', specifying the return code to be given from an - external function that is passed to PCRE and used for stack checking - during compilation (see the pcreapi documentation for details). - - The /S modifier causes pcre[16|32]_study() to be called after the - expression has been compiled, and the results used when the expression - is matched. There are a number of qualifying characters that may follow - /S. They may appear in any order. - - If /S is followed by an exclamation mark, pcre[16|32]_study() is called - with the PCRE_STUDY_EXTRA_NEEDED option, causing it always to return a - pcre_extra block, even when studying discovers no useful information. - - If /S is followed by a second S character, it suppresses studying, even - if it was requested externally by the -s command line option. This - makes it possible to specify that certain patterns are always studied, - and others are never studied, independently of -s. This feature is used - in the test files in a few cases where the output is different when the - pattern is studied. - - If the /S modifier is followed by a + character, the call to - pcre[16|32]_study() is made with all the JIT study options, requesting - just-in-time optimization support if it is available, for both normal - and partial matching. If you want to restrict the JIT compiling modes, - you can follow /S+ with a digit in the range 1 to 7: - - 1 normal match only - 2 soft partial match only - 3 normal match and soft partial match - 4 hard partial match only - 6 soft and hard partial match - 7 all three modes (default) - - If /S++ is used instead of /S+ (with or without a following digit), the - text "(JIT)" is added to the first output line after a match or no - match when JIT-compiled code was actually used. - - Note that there is also an independent /+ modifier; it must not be - given immediately after /S or /S+ because this will be misinterpreted. - - If JIT studying is successful, the compiled JIT code will automatically - be used when pcre[16|32]_exec() is run, except when incompatible run- - time options are specified. For more details, see the pcrejit documen- - tation. See also the \J escape sequence below for a way of setting the - size of the JIT stack. - - Finally, if /S is followed by a minus character, JIT compilation is - suppressed, even if it was requested externally by the -s command line - option. This makes it possible to specify that JIT is never to be used - for certain patterns. - - The /T modifier must be followed by a single digit. It causes a spe- - cific set of built-in character tables to be passed to pcre[16|32]_com- - pile(). It is used in the standard PCRE tests to check behaviour with - different character tables. The digit specifies the tables as follows: - - 0 the default ASCII tables, as distributed in - pcre_chartables.c.dist - 1 a set of tables defining ISO 8859 characters - - In table 1, some characters whose codes are greater than 128 are iden- - tified as letters, digits, spaces, etc. - - Using the POSIX wrapper API - - The /P modifier causes pcretest to call PCRE via the POSIX wrapper API - rather than its native API. This supports only the 8-bit library. When - /P is set, the following modifiers set options for the regcomp() func- - tion: - - /i REG_ICASE - /m REG_NEWLINE - /N REG_NOSUB - /s REG_DOTALL ) - /U REG_UNGREEDY ) These options are not part of - /W REG_UCP ) the POSIX standard - /8 REG_UTF8 ) - - The /+ modifier works as described above. All other modifiers are - ignored. - - Locking out certain modifiers - - PCRE can be compiled with or without support for certain features such - as UTF-8/16/32 or Unicode properties. Accordingly, the standard tests - are split up into a number of different files that are selected for - running depending on which features are available. When updating the - tests, it is all too easy to put a new test into the wrong file by mis- - take; for example, to put a test that requires UTF support into a file - that is used when it is not available. To help detect such mistakes as - early as possible, there is a facility for locking out specific modi- - fiers. If an input line for pcretest starts with the string "< forbid " - the following sequence of characters is taken as a list of forbidden - modifiers. For example, in the test files that must not use UTF or Uni- - code property support, this line appears: - - < forbid 8W - - This locks out the /8 and /W modifiers. An immediate error is given if - they are subsequently encountered. If the character string contains < - but not >, all the multi-character modifiers that begin with < are - locked out. Otherwise, such modifiers must be explicitly listed, for - example: - - < forbid <JS><cr> - - There must be a single space between < and "forbid" for this feature to - be recognised. If there is not, the line is interpreted either as a - request to re-load a pre-compiled pattern (see "SAVING AND RELOADING - COMPILED PATTERNS" below) or, if there is a another < character, as a - pattern that uses < as its delimiter. - - -DATA LINES - - Before each data line is passed to pcre[16|32]_exec(), leading and - trailing white space 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 - "ordinary" regular expressions, you probably don't need any of these. - The following escapes are recognized: - - \a alarm (BEL, \x07) - \b backspace (\x08) - \e escape (\x27) - \f form feed (\x0c) - \n newline (\x0a) - \qdd set the PCRE_MATCH_LIMIT limit to dd - (any number of digits) - \r carriage return (\x0d) - \t tab (\x09) - \v vertical tab (\x0b) - \nnn octal character (up to 3 octal digits); always - a byte unless > 255 in UTF-8 or 16-bit or 32-bit mode - \o{dd...} octal character (any number of octal digits} - \xhh hexadecimal byte (up to 2 hex digits) - \x{hh...} hexadecimal character (any number of hex digits) - \A pass the PCRE_ANCHORED option to pcre[16|32]_exec() - or pcre[16|32]_dfa_exec() - \B pass the PCRE_NOTBOL option to pcre[16|32]_exec() - or pcre[16|32]_dfa_exec() - \Cdd call pcre[16|32]_copy_substring() for substring dd - after a successful match (number less than 32) - \Cname call pcre[16|32]_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 - \D use the pcre[16|32]_dfa_exec() match function - \F only shortest match for pcre[16|32]_dfa_exec() - \Gdd call pcre[16|32]_get_substring() for substring dd - after a successful match (number less than 32) - \Gname call pcre[16|32]_get_named_substring() for substring - "name" after a successful match (name termin- - ated by next non-alphanumeric character) - \Jdd set up a JIT stack of dd kilobytes maximum (any - number of digits) - \L call pcre[16|32]_get_substringlist() after a - successful match - \M discover the minimum MATCH_LIMIT and - MATCH_LIMIT_RECURSION settings - \N pass the PCRE_NOTEMPTY option to pcre[16|32]_exec() - or pcre[16|32]_dfa_exec(); if used twice, pass the - PCRE_NOTEMPTY_ATSTART option - \Odd set the size of the output vector passed to - pcre[16|32]_exec() to dd (any number of digits) - \P pass the PCRE_PARTIAL_SOFT option to pcre[16|32]_exec() - or pcre[16|32]_dfa_exec(); if used twice, pass the - PCRE_PARTIAL_HARD option - \Qdd set the PCRE_MATCH_LIMIT_RECURSION limit to dd - (any number of digits) - \R pass the PCRE_DFA_RESTART option to pcre[16|32]_dfa_exec() - \S output details of memory get/free calls during matching - \Y pass the PCRE_NO_START_OPTIMIZE option to - pcre[16|32]_exec() - or pcre[16|32]_dfa_exec() - \Z pass the PCRE_NOTEOL option to pcre[16|32]_exec() - or pcre[16|32]_dfa_exec() - \? pass the PCRE_NO_UTF[8|16|32]_CHECK option to - pcre[16|32]_exec() or pcre[16|32]_dfa_exec() - \>dd start the match at offset dd (optional "-"; then - any number of digits); this sets the startoffset - argument for pcre[16|32]_exec() or - pcre[16|32]_dfa_exec() - \<cr> pass the PCRE_NEWLINE_CR option to pcre[16|32]_exec() - or pcre[16|32]_dfa_exec() - \<lf> pass the PCRE_NEWLINE_LF option to pcre[16|32]_exec() - or pcre[16|32]_dfa_exec() - \<crlf> pass the PCRE_NEWLINE_CRLF option to pcre[16|32]_exec() - or pcre[16|32]_dfa_exec() - \<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to pcre[16|32]_exec() - or pcre[16|32]_dfa_exec() - \<any> pass the PCRE_NEWLINE_ANY option to pcre[16|32]_exec() - or pcre[16|32]_dfa_exec() - - The use of \x{hh...} is not dependent on the use of the /8 modifier on - the pattern. It is recognized always. There may be any number of hexa- - decimal digits inside the braces; invalid values provoke error mes- - sages. - - Note that \xhh specifies one byte rather than one character in UTF-8 - mode; this makes it possible to construct invalid UTF-8 sequences for - testing purposes. On the other hand, \x{hh} is interpreted as a UTF-8 - character in UTF-8 mode, generating more than one byte if the value is - greater than 127. When testing the 8-bit library not in UTF-8 mode, - \x{hh} generates one byte for values less than 256, and causes an error - for greater values. - - In UTF-16 mode, all 4-digit \x{hhhh} values are accepted. This makes it - possible to construct invalid UTF-16 sequences for testing purposes. - - In UTF-32 mode, all 4- to 8-digit \x{...} values are accepted. This - makes it possible to construct invalid UTF-32 sequences for testing - purposes. - - The escapes that specify line ending sequences are literal strings, - exactly as shown. No more than one newline setting should be present in - any data line. - - A backslash followed by anything else just escapes the anything else. - If the very last character is a backslash, it is ignored. This gives a - way of passing an empty line as data, since a real empty line termi- - nates the data input. - - The \J escape provides a way of setting the maximum stack size that is - used by the just-in-time optimization code. It is ignored if JIT opti- - mization is not being used. Providing a stack that is larger than the - default 32K is necessary only for very complicated patterns. - - If \M is present, pcretest calls pcre[16|32]_exec() several times, with - different values in the match_limit and match_limit_recursion fields of - the pcre[16|32]_extra data structure, until it finds the minimum num- - bers for each parameter that allow pcre[16|32]_exec() to complete with- - out error. Because this is testing a specific feature of the normal - interpretive pcre[16|32]_exec() execution, the use of any JIT optimiza- - tion that might have been set up by the /S+ qualifier of -s+ option is - disabled. - - The match_limit number is a measure of the amount of backtracking that - takes place, and checking it out can be instructive. For most simple - matches, the number is quite small, but for patterns with very large - numbers of matching possibilities, it can become large very quickly - with increasing length of subject string. The match_limit_recursion - number is a measure of how much stack (or, if PCRE is compiled with - NO_RECURSE, how much heap) memory is needed to complete the match - attempt. - - When \O is used, the value specified may be higher or lower than the - size set by the -O command line option (or defaulted to 45); \O applies - only to the call of pcre[16|32]_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, the only option-setting sequences that have any - effect are \B, \N, and \Z, causing REG_NOTBOL, REG_NOTEMPTY, and - REG_NOTEOL, respectively, to be passed to regexec(). - - -THE ALTERNATIVE MATCHING FUNCTION - - By default, pcretest uses the standard PCRE matching function, - pcre[16|32]_exec() to match each data line. PCRE also supports an - alternative matching function, pcre[16|32]_dfa_test(), which operates - in a different way, and has some restrictions. The differences between - the two functions are described in the pcrematching documentation. - - If a data line contains the \D escape sequence, or if the command line - contains the -dfa option, the alternative matching function is used. - This function finds all possible matches at a given point. If, however, - the \F escape sequence is present in the data line, it stops after the - first match is found. This is always the shortest possible match. - - -DEFAULT OUTPUT FROM PCRETEST - - This section describes the output when the normal matching function, - pcre[16|32]_exec(), is being used. - - When a match succeeds, pcretest outputs the list of captured substrings - that pcre[16|32]_exec() returns, starting with number 0 for the string - that matched the whole pattern. Otherwise, it outputs "No match" when - the return is PCRE_ERROR_NOMATCH, and "Partial match:" followed by the - partially matching substring when pcre[16|32]_exec() returns - PCRE_ERROR_PARTIAL. (Note that this is the entire substring that was - inspected during the partial match; it may include characters before - the actual match start if a lookbehind assertion, \K, \b, or \B was - involved.) For any other return, pcretest outputs the PCRE negative - error number and a short descriptive phrase. If the error is a failed - UTF string check, the offset of the start of the failing character and - the reason code are also output, provided that the size of the output - vector is at least two. Here is an example of an interactive pcretest - run. - - $ pcretest - PCRE version 8.13 2011-04-30 - - re> /^abc(\d+)/ - data> abc123 - 0: abc123 - 1: 123 - data> xyz - No match - - Unset capturing substrings that are not followed by one that is set are - not returned by pcre[16|32]_exec(), and are not shown by pcretest. In - the following example, there are two capturing substrings, but when the - first data line is matched, the second, unset substring is not shown. - An "internal" unset substring is shown as "<unset>", as for the second - data line. - - re> /(a)|(b)/ - data> a - 0: a - 1: a - data> b - 0: b - 1: <unset> - 2: b - - If the strings contain any non-printing characters, they are output as - \xhh escapes if the value is less than 256 and UTF mode is not set. - Otherwise they are output as \x{hh...} escapes. See below for the defi- - nition of non-printing characters. If the pattern has the /+ modifier, - 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. Here is an - example of a failure message (the offset 4 that is specified by \>4 is - past the end of the subject string): - - re> /xyz/ - data> xyz\>4 - Error -24 (bad offset value) - - 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 whereas patterns can be continued over several lines (a plain - ">" prompt is used for continuations), data lines may not. However new- - lines can be included in data by means of the \n escape (or \r, \r\n, - etc., depending on the newline sequence setting). - - -OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION - - When the alternative matching function, pcre[16|32]_dfa_exec(), is used - (by means of the \D escape sequence or the -dfa command line option), - the output consists of a list of all the matches that start at the - first point in the subject where there is at least one match. For exam- - ple: - - re> /(tang|tangerine|tan)/ - data> yellow tangerine\D - 0: tangerine - 1: tang - 2: tan - - (Using the normal matching function on this data finds only "tang".) - The longest matching string is always given first (and numbered zero). - After a PCRE_ERROR_PARTIAL return, the output is "Partial match:", fol- - lowed by the partially matching substring. (Note that this is the - entire substring that was inspected during the partial match; it may - include characters before the actual match start if a lookbehind asser- - tion, \K, \b, or \B was involved.) - - If /g is present on the pattern, the search for further matches resumes - at the end of the longest match. For example: - - re> /(tang|tangerine|tan)/g - data> yellow tangerine and tangy sultana\D - 0: tangerine - 1: tang - 2: tan - 0: tang - 1: tan - 0: tan - - Since the matching function does not support substring capture, the - escape sequences that are concerned with captured substrings are not - relevant. - - -RESTARTING AFTER A PARTIAL MATCH - - When the alternative matching function has given the PCRE_ERROR_PARTIAL - return, indicating that the subject partially matched the pattern, you - can restart the match with additional subject data by means of the \R - escape sequence. For example: - - re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/ - data> 23ja\P\D - Partial match: 23ja - data> n05\R\D - 0: n05 - - For further information about partial matching, see the pcrepartial - documentation. - - -CALLOUTS - - If the pattern contains any callout requests, pcretest's callout func- - tion is called during matching. This works with both matching func- - tions. By default, the called function 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: - - --->pqrabcdef - 0 ^ ^ \d - - This output 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* - - If a pattern contains (*MARK) items, an additional line is output when- - ever a change of latest mark is passed to the callout function. For - example: - - re> /a(*MARK:X)bc/C - data> abc - --->abc - +0 ^ a - +1 ^^ (*MARK:X) - +10 ^^ b - Latest Mark: X - +11 ^ ^ c - +12 ^ ^ - 0: abc - - The mark changes between matching "a" and "b", but stays the same for - the rest of the match, so nothing more is output. If, as a result of - backtracking, the mark reverts to being unset, the text "<unset>" is - output. - - The callout function in pcretest returns zero (carry on matching) by - default, but you can use a \C item in a data line (as described above) - to change this and other parameters of the callout. - - Inserting callouts can be helpful when using pcretest to check compli- - cated regular expressions. For further information about callouts, see - the pcrecallout documentation. - - -NON-PRINTING CHARACTERS - - When pcretest is outputting text in the compiled version of a pattern, - bytes other than 32-126 are always treated as non-printing characters - are are therefore shown as hex escapes. - - When pcretest is outputting text that is a matched part of a subject - string, it behaves in the same way, unless a different locale has been - set for the pattern (using the /L modifier). In this case, the - isprint() function to distinguish printing and non-printing characters. - - -SAVING AND RELOADING COMPILED PATTERNS - - The facilities described in this section are not available when the - POSIX interface to PCRE is being used, that is, when the /P pattern - modifier 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. Note that if the pattern was successfully - studied with JIT optimization, the JIT data cannot be saved. - - 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 (excluding - any JIT data) follows immediately after the compiled pattern. After - writing the file, pcretest expects to read a new pattern. - - A saved pattern can be reloaded into pcretest by specifying < and a - file name instead of a pattern. There must be no space between < and - the file name, which must not contain a < character, as otherwise - pcretest will interpret the line as a pattern delimited by < charac- - ters. For example: - - re> </some/file - Compiled pattern loaded from /some/file - No study data - - If the pattern was previously studied with the JIT optimization, the - JIT information cannot be saved and restored, and so is lost. 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. When a pattern is reloaded on a - host with different endianness, the confirmation message is changed to: - - Compiled pattern (byte-inverted) loaded from /some/file - - The test suite contains some saved pre-compiled patterns with different - endianness. These are reloaded using "<!" instead of just "<". This - suppresses the "(byte-inverted)" text so that the output is the same on - all hosts. It also forces debugging output once the pattern has been - reloaded. - - 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. - - -SEE ALSO - - pcre(3), pcre16(3), pcre32(3), pcreapi(3), pcrecallout(3), pcrejit, - pcrematching(3), pcrepartial(d), pcrepattern(3), pcreprecompile(3). - - -AUTHOR - - Philip Hazel - University Computing Service - Cambridge CB2 3QH, England. - - -REVISION - - Last updated: 23 February 2017 - Copyright (c) 1997-2017 University of Cambridge. |