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 diff --git a/doc/pcretest.1 b/doc/pcretest.1new file mode 100644index 0000000..92640da--- /dev/null+++ b/doc/pcretest.1@@ -0,0 +1,1156 @@+.TH PCRETEST 1 "09 February 2014" "PCRE 8.35"+.SH NAME+pcretest - a program for testing Perl-compatible regular expressions.+.SH SYNOPSIS+.rs+.sp+.B pcretest "[options] [input file [output file]]"+.sp+\fBpcretest\fP 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+.\" HREF+\fBpcrepattern\fP+.\"+documentation. For details of the PCRE library function calls and their+options, see the+.\" HREF+\fBpcreapi\fP+.\"+,+.\" HREF+\fBpcre16\fP+and+.\" HREF+\fBpcre32\fP+.\"+documentation.+.P+The input for \fBpcretest\fP 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.+.P+As PCRE has evolved, it has acquired many different features, and as a result,+\fBpcretest\fP 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.+.+.+.SH "INPUT DATA FORMAT"+.rs+.sp+Input to \fBpcretest\fP is processed line by line, either by calling the C+library's \fBfgets()\fP function, or via the \fBlibreadline\fP library (see+below). In Unix-like environments, \fBfgets()\fP 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+\fBpcretest\fP input files.+.+.+.SH "PCRE's 8-BIT, 16-BIT AND 32-BIT LIBRARIES"+.rs+.sp+From release 8.30, two separate PCRE libraries can be built. The original 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+\fBpcretest\fP 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.+.P+References to functions and structures of the form \fBpcre[16|32]_xx\fP below+mean "\fBpcre_xx\fP when using the 8-bit library, \fBpcre16_xx\fP when using+the 16-bit library, or \fBpcre32_xx\fP when using the 32-bit library".+.+.+.SH "COMMAND LINE OPTIONS"+.rs+.TP 10+\fB-8\fP+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.+.TP 10+\fB-16\fP+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.+.TP 10+\fB-32\fP+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.+.TP 10+\fB-b\fP+Behave as if each pattern has the \fB/B\fP (show byte code) modifier; the+internal form is output after compilation.+.TP 10+\fB-C\fP+Output the version number of the PCRE library, and all available information+about the optional features that are included, and then exit with zero exit+code. All other options are ignored.+.TP 10+\fB-C\fP \fIoption\fP+Output information about a specific build-time option, then exit. This+functionality is intended for use in scripts such as \fBRunTest\fP. The+following options output the value and set the exit code as indicated:+.sp+ 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 \eR matches:+ ANYCRLF or ANY+ exit code is always 0+.sp+The following options output 1 for true or 0 for false, and set the exit code+to the same value:+.sp+ 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+.sp+If an unknown option is given, an error message is output; the exit code is 0.+.TP 10+\fB-d\fP+Behave as if each pattern has the \fB/D\fP (debug) modifier; the internal+form and information about the compiled pattern is output after compilation;+\fB-d\fP is equivalent to \fB-b -i\fP.+.TP 10+\fB-dfa\fP+Behave as if each data line contains the \eD escape sequence; this causes the+alternative matching function, \fBpcre[16|32]_dfa_exec()\fP, to be used instead+of the standard \fBpcre[16|32]_exec()\fP function (more detail is given below).+.TP 10+\fB-help\fP+Output a brief summary these options and then exit.+.TP 10+\fB-i\fP+Behave as if each pattern has the \fB/I\fP modifier; information about the+compiled pattern is given after compilation.+.TP 10+\fB-M\fP+Behave as if each data line contains the \eM escape sequence; this causes+PCRE to discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings by+calling \fBpcre[16|32]_exec()\fP repeatedly with different limits.+.TP 10+\fB-m\fP+Output the size of each compiled pattern after it has been compiled. This is+equivalent to adding \fB/M\fP to each regular expression. The size is given in+bytes for both libraries.+.TP 10+\fB-O\fP+Behave as if each pattern has the \fB/O\fP modifier, that is disable+auto-possessification for all patterns.+.TP 10+\fB-o\fP \fIosize\fP+Set the number of elements in the output vector that is used when calling+\fBpcre[16|32]_exec()\fP or \fBpcre[16|32]_dfa_exec()\fP to be \fIosize\fP. The+default value is 45, which is enough for 14 capturing subexpressions for+\fBpcre[16|32]_exec()\fP or 22 different matches for+\fBpcre[16|32]_dfa_exec()\fP.+The vector size can be changed for individual matching calls by including \eO+in the data line (see below).+.TP 10+\fB-p\fP+Behave as if each pattern has the \fB/P\fP modifier; the POSIX wrapper API is+used to call PCRE. None of the other options has any effect when \fB-p\fP is+set. This option can be used only with the 8-bit library.+.TP 10+\fB-q\fP+Do not output the version number of \fBpcretest\fP at the start of execution.+.TP 10+\fB-S\fP \fIsize\fP+On Unix-like systems, set the size of the run-time stack to \fIsize\fP+megabytes.+.TP 10+\fB-s\fP or \fB-s+\fP+Behave as if each pattern has the \fB/S\fP modifier; in other words, force each+pattern to be studied. If \fB-s+\fP is used, all the JIT compile options are+passed to \fBpcre[16|32]_study()\fP, 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 \fB-s+\fP with a digit in the range 1 to+7, which selects the JIT compile modes as follows:+.sp+ 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)+.sp+If \fB-s++\fP is used instead of \fB-s+\fP (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.+.sp+Note that there are pattern options that can override \fB-s\fP, either+specifying no studying at all, or suppressing JIT compilation.+.sp+If the \fB/I\fP or \fB/D\fP 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 \fB-s\fP and neither \fB-i\fP nor+\fB-d\fP is present on the command line. This behaviour means that the output+from tests that are run with and without \fB-s\fP should be identical, except+when options that output information about the actual running of a match are+set.+.sp+The \fB-M\fP, \fB-t\fP, and \fB-tm\fP options, which give information about+resources used, are likely to produce different output with and without+\fB-s\fP. Output may also differ if the \fB/C\fP 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+\fB-s\fP command line option can be overridden for specific patterns that+should never be studied (see the \fB/S\fP pattern modifier below).+.TP 10+\fB-t\fP+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+\fB-m\fP with \fB-t\fP, 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 \fB-t\fP with a number (as a+separate item on the command line). For example, "-t 1000" iterates 1000 times.+The default is to iterate 500000 times.+.TP 10+\fB-tm\fP+This is like \fB-t\fP except that it times only the matching phase, not the+compile or study phases.+.TP 10+\fB-T\fP \fB-TM\fP+These behave like \fB-t\fP and \fB-tm\fP, but in addition, at the end of a run,+the total times for all compiles, studies, and matches are output.+.+.+.SH DESCRIPTION+.rs+.sp+If \fBpcretest\fP 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.+.P+When \fBpcretest\fP is built, a configuration option can specify that it should+be linked with the \fBlibreadline\fP library. When this is done, if the input+is from a terminal, it is read using the \fBreadline()\fP function. This+provides line-editing and history facilities. The output from the \fB-help\fP+option states whether or not \fBreadline()\fP will be used.+.P+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 that pattern.+.P+Each data line is matched separately and independently. If you want to do+multi-line matches, you have to use the \en escape sequence (or \er or \er\en,+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.+.P+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:+.sp+ /(a|bc)x+yz/+.sp+White space before the initial delimiter is ignored. A regular 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+.sp+ /abc\e/def/+.sp+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 followed by a backslash, for+example,+.sp+ /abc/\e+.sp+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+.sp+ /abc\e/+.sp+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.+.+.+.SH "PATTERN MODIFIERS"+.rs+.sp+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+\fB/i\fP modifier", even though the delimiter of the pattern need not always be+a slash, and no slash is used when writing modifiers. White space may appear+between the final pattern delimiter and the first modifier, and between the+modifiers themselves. For reference, here is a complete list of modifiers. They+fall into several groups that are described in detail in the following+sections.+.sp+ \fB/8\fP set UTF mode+ \fB/9\fP set PCRE_NEVER_UTF (locks out UTF mode)+ \fB/?\fP disable UTF validity check+ \fB/+\fP show remainder of subject after match+ \fB/=\fP show all captures (not just those that are set)+.sp+ \fB/A\fP set PCRE_ANCHORED+ \fB/B\fP show compiled code+ \fB/C\fP set PCRE_AUTO_CALLOUT+ \fB/D\fP same as \fB/B\fP plus \fB/I\fP+ \fB/E\fP set PCRE_DOLLAR_ENDONLY+ \fB/F\fP flip byte order in compiled pattern+ \fB/f\fP set PCRE_FIRSTLINE+ \fB/G\fP find all matches (shorten string)+ \fB/g\fP find all matches (use startoffset)+ \fB/I\fP show information about pattern+ \fB/i\fP set PCRE_CASELESS+ \fB/J\fP set PCRE_DUPNAMES+ \fB/K\fP show backtracking control names+ \fB/L\fP set locale+ \fB/M\fP show compiled memory size+ \fB/m\fP set PCRE_MULTILINE+ \fB/N\fP set PCRE_NO_AUTO_CAPTURE+ \fB/O\fP set PCRE_NO_AUTO_POSSESS+ \fB/P\fP use the POSIX wrapper+ \fB/Q\fP test external stack check function+ \fB/S\fP study the pattern after compilation+ \fB/s\fP set PCRE_DOTALL+ \fB/T\fP select character tables+ \fB/U\fP set PCRE_UNGREEDY+ \fB/W\fP set PCRE_UCP+ \fB/X\fP set PCRE_EXTRA+ \fB/x\fP set PCRE_EXTENDED+ \fB/Y\fP set PCRE_NO_START_OPTIMIZE+ \fB/Z\fP don't show lengths in \fB/B\fP output+.sp+ \fB/\fP set PCRE_NEWLINE_ANY+ \fB/\fP set PCRE_NEWLINE_ANYCRLF+ \fB/\fP set PCRE_NEWLINE_CR+ \fB/\fP set PCRE_NEWLINE_CRLF+ \fB/\fP set PCRE_NEWLINE_LF+ \fB/\fP set PCRE_BSR_ANYCRLF+ \fB/\fP set PCRE_BSR_UNICODE+ \fB/\fP set PCRE_JAVASCRIPT_COMPAT+.sp+.+.+.SS "Perl-compatible modifiers"+.rs+.sp+The \fB/i\fP, \fB/m\fP, \fB/s\fP, and \fB/x\fP modifiers set the PCRE_CASELESS,+PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when+\fBpcre[16|32]_compile()\fP is called. These four modifier letters have the same+effect as they do in Perl. For example:+.sp+ /caseless/i+.sp+.+.+.SS "Modifiers for other PCRE options"+.rs+.sp+The following table shows additional modifiers for setting PCRE compile-time+options that do not correspond to anything in Perl:+.sp+ \fB/8\fP PCRE_UTF8 ) when using the 8-bit+ \fB/?\fP PCRE_NO_UTF8_CHECK ) library+.sp+ \fB/8\fP PCRE_UTF16 ) when using the 16-bit+ \fB/?\fP PCRE_NO_UTF16_CHECK ) library+.sp+ \fB/8\fP PCRE_UTF32 ) when using the 32-bit+ \fB/?\fP PCRE_NO_UTF32_CHECK ) library+.sp+ \fB/9\fP PCRE_NEVER_UTF+ \fB/A\fP PCRE_ANCHORED+ \fB/C\fP PCRE_AUTO_CALLOUT+ \fB/E\fP PCRE_DOLLAR_ENDONLY+ \fB/f\fP PCRE_FIRSTLINE+ \fB/J\fP PCRE_DUPNAMES+ \fB/N\fP PCRE_NO_AUTO_CAPTURE+ \fB/O\fP PCRE_NO_AUTO_POSSESS+ \fB/U\fP PCRE_UNGREEDY+ \fB/W\fP PCRE_UCP+ \fB/X\fP PCRE_EXTRA+ \fB/Y\fP PCRE_NO_START_OPTIMIZE+ \fB/\fP PCRE_NEWLINE_ANY+ \fB/\fP PCRE_NEWLINE_ANYCRLF+ \fB/\fP PCRE_NEWLINE_CR+ \fB/\fP PCRE_NEWLINE_CRLF+ \fB/\fP PCRE_NEWLINE_LF+ \fB/\fP PCRE_BSR_ANYCRLF+ \fB/\fP PCRE_BSR_UNICODE+ \fB/\fP PCRE_JAVASCRIPT_COMPAT+.sp+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:+.sp+ /^abc/m+.sp+As well as turning on the PCRE_UTF8/16/32 option, the \fB/8\fP modifier causes+all non-printing characters in output strings to be printed using the+\ex{hh...} notation. Otherwise, those less than 0x100 are output in hex without+the curly brackets.+.P+Full details of the PCRE options are given in the+.\" HREF+\fBpcreapi\fP+.\"+documentation.+.+.+.SS "Finding all matches in a string"+.rs+.sp+Searching for all possible matches within each subject string can be requested+by the \fB/g\fP or \fB/G\fP modifier. After finding a match, PCRE is called+again to search the remainder of the subject string. The difference between+\fB/g\fP and \fB/G\fP is that the former uses the \fIstartoffset\fP argument to+\fBpcre[16|32]_exec()\fP 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 \eb or \eB).+.P+If any call to \fBpcre[16|32]_exec()\fP in a \fB/g\fP or \fB/G\fP 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 \fB/g\fP modifier or the \fBsplit()\fP function. 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.+.+.+.SS "Other modifiers"+.rs+.sp+There are yet more modifiers for controlling the way \fBpcretest\fP+operates.+.P+The \fB/+\fP modifier requests that as well as outputting the substring that+matched the entire pattern, \fBpcretest\fP 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 \fB+\fP modifier 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.+.P+The \fB/=\fP 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 \fBpcre[16|32]_exec()\fP). Values in the offsets vector corresponding to+higher numbers should be set to -1, and these are output as "". This+modifier gives a way of checking that this is happening.+.P+The \fB/B\fP modifier is a debugging feature. It requests that \fBpcretest\fP+output a representation of the compiled code after compilation. Normally this+information contains length and offset values; however, if \fB/Z\fP is also+present, this data is replaced by spaces. This is a special feature for use in+the automatic test scripts; it ensures that the same output is generated for+different internal link sizes.+.P+The \fB/D\fP modifier is a PCRE debugging feature, and is equivalent to+\fB/BI\fP, that is, both the \fB/B\fP and the \fB/I\fP modifiers.+.P+The \fB/F\fP modifier causes \fBpcretest\fP 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 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 \fB/P\fP pattern modifier is+specified. See also the section about saving and reloading compiled patterns+below.+.P+The \fB/I\fP modifier requests that \fBpcretest\fP output information about the+compiled pattern (whether it is anchored, has a fixed first character, and+so on). It does this by calling \fBpcre[16|32]_fullinfo()\fP after compiling 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).+.P+The \fB/K\fP modifier requests \fBpcretest\fP to show names from backtracking+control verbs that are returned from calls to \fBpcre[16|32]_exec()\fP. It causes+\fBpcretest\fP to create a \fBpcre[16|32]_extra\fP block if one has not already+been created by a call to \fBpcre[16|32]_study()\fP, and to set the+PCRE_EXTRA_MARK flag and the \fBmark\fP field within it, every time that+\fBpcre[16|32]_exec()\fP is called. If the variable that the \fBmark\fP field+points to is non-NULL for a match, non-match, or partial match, \fBpcretest\fP+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.+.P+The \fB/L\fP modifier must be followed directly by the name of a locale, for+example,+.sp+ /pattern/Lfr_FR+.sp+For this reason, it must be the last modifier. The given locale is set,+\fBpcre[16|32]_maketables()\fP is called to build a set of character tables for+the locale, and this is then passed to \fBpcre[16|32]_compile()\fP when compiling+the regular expression. Without an \fB/L\fP (or \fB/T\fP) modifier, NULL is+passed as the tables pointer; that is, \fB/L\fP applies only to the expression+on which it appears.+.P+The \fB/M\fP 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+\fBpcre[16|32]\fP 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.+.P+The \fB/Q\fP modifier is used to test the use of \fBpcre_stack_guard\fP. 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+.\" HREF+\fBpcreapi\fP+.\"+documentation for details).+.P+The \fB/S\fP modifier causes \fBpcre[16|32]_study()\fP 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 \fB/S\fP.+They may appear in any order.+.P+If \fB/S\fP is followed by an exclamation mark, \fBpcre[16|32]_study()\fP is+called with the PCRE_STUDY_EXTRA_NEEDED option, causing it always to return a+\fBpcre_extra\fP block, even when studying discovers no useful information.+.P+If \fB/S\fP is followed by a second S character, it suppresses studying, even+if it was requested externally by the \fB-s\fP command line option. This makes+it possible to specify that certain patterns are always studied, and others are+never studied, independently of \fB-s\fP. This feature is used in the test+files in a few cases where the output is different when the pattern is studied.+.P+If the \fB/S\fP modifier is followed by a + character, the call to+\fBpcre[16|32]_study()\fP 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 \fB/S+\fP with a digit in the range 1 to 7:+.sp+ 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)+.sp+If \fB/S++\fP is used instead of \fB/S+\fP (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.+.P+Note that there is also an independent \fB/+\fP modifier; it must not be given+immediately after \fB/S\fP or \fB/S+\fP because this will be misinterpreted.+.P+If JIT studying is successful, the compiled JIT code will automatically be used+when \fBpcre[16|32]_exec()\fP is run, except when incompatible run-time options+are specified. For more details, see the+.\" HREF+\fBpcrejit\fP+.\"+documentation. See also the \fB\eJ\fP escape sequence below for a way of+setting the size of the JIT stack.+.P+Finally, if \fB/S\fP is followed by a minus character, JIT compilation is+suppressed, even if it was requested externally by the \fB-s\fP command line+option. This makes it possible to specify that JIT is never to be used for+certain patterns.+.P+The \fB/T\fP modifier must be followed by a single digit. It causes a specific+set of built-in character tables to be passed to \fBpcre[16|32]_compile()\fP. It+is used in the standard PCRE tests to check behaviour with different character+tables. The digit specifies the tables as follows:+.sp+ 0 the default ASCII tables, as distributed in+ pcre_chartables.c.dist+ 1 a set of tables defining ISO 8859 characters+.sp+In table 1, some characters whose codes are greater than 128 are identified as+letters, digits, spaces, etc.+.+.+.SS "Using the POSIX wrapper API"+.rs+.sp+The \fB/P\fP modifier causes \fBpcretest\fP to call PCRE via the POSIX wrapper+API rather than its native API. This supports only the 8-bit library. When+\fB/P\fP is set, the following modifiers set options for the \fBregcomp()\fP+function:+.sp+ /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 )+.sp+The \fB/+\fP modifier works as described above. All other modifiers are+ignored.+.+.+.SS "Locking out certain modifiers"+.rs+.sp+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 mistake; 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 modifiers. If an input line for \fBpcretest\fP 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+Unicode property support, this line appears:+.sp+ < forbid 8W+.sp+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:+.sp+ < forbid +.sp+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.+.+.+.SH "DATA LINES"+.rs+.sp+Before each data line is passed to \fBpcre[16|32]_exec()\fP, leading and trailing+white space is removed, and it is then scanned for \e 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:+.sp+ \ea alarm (BEL, \ex07)+ \eb backspace (\ex08)+ \ee escape (\ex27)+ \ef form feed (\ex0c)+ \en newline (\ex0a)+.\" JOIN+ \eqdd set the PCRE_MATCH_LIMIT limit to dd+ (any number of digits)+ \er carriage return (\ex0d)+ \et tab (\ex09)+ \ev vertical tab (\ex0b)+ \ennn octal character (up to 3 octal digits); always+ a byte unless > 255 in UTF-8 or 16-bit or 32-bit mode+ \eo{dd...} octal character (any number of octal digits}+ \exhh hexadecimal byte (up to 2 hex digits)+ \ex{hh...} hexadecimal character (any number of hex digits)+.\" JOIN+ \eA pass the PCRE_ANCHORED option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \eB pass the PCRE_NOTBOL option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \eCdd call pcre[16|32]_copy_substring() for substring dd+ after a successful match (number less than 32)+.\" JOIN+ \eCname call pcre[16|32]_copy_named_substring() for substring+ "name" after a successful match (name termin-+ ated by next non alphanumeric character)+.\" JOIN+ \eC+ show the current captured substrings at callout+ time+ \eC- do not supply a callout function+.\" JOIN+ \eC!n return 1 instead of 0 when callout number n is+ reached+.\" JOIN+ \eC!n!m return 1 instead of 0 when callout number n is+ reached for the nth time+.\" JOIN+ \eC*n pass the number n (may be negative) as callout+ data; this is used as the callout return value+ \eD use the \fBpcre[16|32]_dfa_exec()\fP match function+ \eF only shortest match for \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \eGdd call pcre[16|32]_get_substring() for substring dd+ after a successful match (number less than 32)+.\" JOIN+ \eGname call pcre[16|32]_get_named_substring() for substring+ "name" after a successful match (name termin-+ ated by next non-alphanumeric character)+.\" JOIN+ \eJdd set up a JIT stack of dd kilobytes maximum (any+ number of digits)+.\" JOIN+ \eL call pcre[16|32]_get_substringlist() after a+ successful match+.\" JOIN+ \eM discover the minimum MATCH_LIMIT and+ MATCH_LIMIT_RECURSION settings+.\" JOIN+ \eN pass the PCRE_NOTEMPTY option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP; if used twice, pass the+ PCRE_NOTEMPTY_ATSTART option+.\" JOIN+ \eOdd set the size of the output vector passed to+ \fBpcre[16|32]_exec()\fP to dd (any number of digits)+.\" JOIN+ \eP pass the PCRE_PARTIAL_SOFT option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP; if used twice, pass the+ PCRE_PARTIAL_HARD option+.\" JOIN+ \eQdd set the PCRE_MATCH_LIMIT_RECURSION limit to dd+ (any number of digits)+ \eR pass the PCRE_DFA_RESTART option to \fBpcre[16|32]_dfa_exec()\fP+ \eS output details of memory get/free calls during matching+.\" JOIN+ \eY pass the PCRE_NO_START_OPTIMIZE option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \eZ pass the PCRE_NOTEOL option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \e? pass the PCRE_NO_UTF[8|16|32]_CHECK option to+ \fBpcre[16|32]_exec()\fP or \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \e>dd start the match at offset dd (optional "-"; then+ any number of digits); this sets the \fIstartoffset\fP+ argument for \fBpcre[16|32]_exec()\fP or \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \e pass the PCRE_NEWLINE_CR option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \e pass the PCRE_NEWLINE_LF option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \e pass the PCRE_NEWLINE_CRLF option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \e pass the PCRE_NEWLINE_ANYCRLF option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP+.\" JOIN+ \e pass the PCRE_NEWLINE_ANY option to \fBpcre[16|32]_exec()\fP+ or \fBpcre[16|32]_dfa_exec()\fP+.sp+The use of \ex{hh...} is not dependent on the use of the \fB/8\fP modifier on+the pattern. It is recognized always. There may be any number of hexadecimal+digits inside the braces; invalid values provoke error messages.+.P+Note that \exhh 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, \ex{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, \ex{hh} generates one byte+for values less than 256, and causes an error for greater values.+.P+In UTF-16 mode, all 4-digit \ex{hhhh} values are accepted. This makes it+possible to construct invalid UTF-16 sequences for testing purposes.+.P+In UTF-32 mode, all 4- to 8-digit \ex{...} values are accepted. This makes it+possible to construct invalid UTF-32 sequences for testing purposes.+.P+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.+.P+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 terminates the data+input.+.P+The \fB\eJ\fP 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 optimization+is not being used. Providing a stack that is larger than the default 32K is+necessary only for very complicated patterns.+.P+If \eM is present, \fBpcretest\fP calls \fBpcre[16|32]_exec()\fP several times,+with different values in the \fImatch_limit\fP and \fImatch_limit_recursion\fP+fields of the \fBpcre[16|32]_extra\fP data structure, until it finds the minimum+numbers for each parameter that allow \fBpcre[16|32]_exec()\fP to complete without+error. Because this is testing a specific feature of the normal interpretive+\fBpcre[16|32]_exec()\fP execution, the use of any JIT optimization that might+have been set up by the \fB/S+\fP qualifier of \fB-s+\fP option is disabled.+.P+The \fImatch_limit\fP 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 \fImatch_limit_recursion\fP 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.+.P+When \eO is used, the value specified may be higher or lower than the size set+by the \fB-O\fP command line option (or defaulted to 45); \eO applies only to+the call of \fBpcre[16|32]_exec()\fP for the line in which it appears.+.P+If the \fB/P\fP modifier was present on the pattern, causing the POSIX wrapper+API to be used, the only option-setting sequences that have any effect are \eB,+\eN, and \eZ, causing REG_NOTBOL, REG_NOTEMPTY, and REG_NOTEOL, respectively,+to be passed to \fBregexec()\fP.+.+.+.SH "THE ALTERNATIVE MATCHING FUNCTION"+.rs+.sp+By default, \fBpcretest\fP uses the standard PCRE matching function,+\fBpcre[16|32]_exec()\fP to match each data line. PCRE also supports an+alternative matching function, \fBpcre[16|32]_dfa_test()\fP, which operates in a+different way, and has some restrictions. The differences between the two+functions are described in the+.\" HREF+\fBpcrematching\fP+.\"+documentation.+.P+If a data line contains the \eD escape sequence, or if the command line+contains the \fB-dfa\fP option, the alternative matching function is used.+This function finds all possible matches at a given point. If, however, the \eF+escape sequence is present in the data line, it stops after the first match is+found. This is always the shortest possible match.+.+.+.SH "DEFAULT OUTPUT FROM PCRETEST"+.rs+.sp+This section describes the output when the normal matching function,+\fBpcre[16|32]_exec()\fP, is being used.+.P+When a match succeeds, \fBpcretest\fP outputs the list of captured substrings+that \fBpcre[16|32]_exec()\fP 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 \fBpcre[16|32]_exec()\fP 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,+\eK, \eb, or \eB was involved.) For any other return, \fBpcretest\fP 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 \fBpcretest\fP run.+.sp+ $pcretest+ PCRE version 8.13 2011-04-30+.sp+ re> /^abc(\ed+)/+ data> abc123+ 0: abc123+ 1: 123+ data> xyz+ No match+.sp+Unset capturing substrings that are not followed by one that is set are not+returned by \fBpcre[16|32]_exec()\fP, and are not shown by \fBpcretest\fP. 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 "", as for the second data line.+.sp+ re> /(a)|(b)/+ data> a+ 0: a+ 1: a+ data> b+ 0: b+ 1: + 2: b+.sp+If the strings contain any non-printing characters, they are output as \exhh+escapes if the value is less than 256 and UTF mode is not set. Otherwise they+are output as \ex{hh...} escapes. See below for the definition of non-printing+characters. If the pattern has the \fB/+\fP modifier, the output for substring+0 is followed by the the rest of the subject string, identified by "0+" like+this:+.sp+ re> /cat/++ data> cataract+ 0: cat+ 0+ aract+.sp+If the pattern has the \fB/g\fP or \fB/G\fP modifier, the results of successive+matching attempts are output in sequence, like this:+.sp+ re> /\eBi(\ew\ew)/g+ data> Mississippi+ 0: iss+ 1: ss+ 0: iss+ 1: ss+ 0: ipp+ 1: pp+.sp+"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 \e>4 is past the end of+the subject string):+.sp+ re> /xyz/+ data> xyz\e>4+ Error -24 (bad offset value)+.P+If any of the sequences \fB\eC\fP, \fB\eG\fP, or \fB\eL\fP 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+parentheses after each string for \fB\eC\fP and \fB\eG\fP.+.P+Note that whereas 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 \en escape (or \er, \er\en, etc., depending on+the newline sequence setting).+.+.+.+.SH "OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION"+.rs+.sp+When the alternative matching function, \fBpcre[16|32]_dfa_exec()\fP, is used (by+means of the \eD escape sequence or the \fB-dfa\fP 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 example:+.sp+ re> /(tang|tangerine|tan)/+ data> yellow tangerine\eD+ 0: tangerine+ 1: tang+ 2: tan+.sp+(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:", followed 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 assertion, \eK, \eb, or \eB was involved.)+.P+If \fB/g\fP is present on the pattern, the search for further matches resumes+at the end of the longest match. For example:+.sp+ re> /(tang|tangerine|tan)/g+ data> yellow tangerine and tangy sultana\eD+ 0: tangerine+ 1: tang+ 2: tan+ 0: tang+ 1: tan+ 0: tan+.sp+Since the matching function does not support substring capture, the escape+sequences that are concerned with captured substrings are not relevant.+.+.+.SH "RESTARTING AFTER A PARTIAL MATCH"+.rs+.sp+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 \eR escape sequence. For+example:+.sp+ re> /^\ed?\ed(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\ed\ed$/+ data> 23ja\eP\eD+ Partial match: 23ja+ data> n05\eR\eD+ 0: n05+.sp+For further information about partial matching, see the+.\" HREF+\fBpcrepartial\fP+.\"+documentation.+.+.+.SH CALLOUTS+.rs+.sp+If the pattern contains any callout requests, \fBpcretest\fP's callout function+is called during matching. This works with both matching functions. 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:+.sp+ --->pqrabcdef+ 0 ^ ^ \ed+.sp+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 \ed. Just+one circumflex is output if the start and current positions are the same.+.P+Callouts numbered 255 are assumed to be automatic callouts, inserted as a+result of the \fB/C\fP pattern modifier. In this case, instead of showing the+callout number, the offset in the pattern, preceded by a plus, is output. For+example:+.sp+ re> /\ed?[A-E]\e*/C+ data> E*+ --->E*+ +0 ^ \ed?+ +3 ^ [A-E]+ +8 ^^ \e*+ +10 ^ ^+ 0: E*+.sp+If a pattern contains (*MARK) items, an additional line is output whenever+a change of latest mark is passed to the callout function. For example:+.sp+ re> /a(*MARK:X)bc/C+ data> abc+ --->abc+ +0 ^ a+ +1 ^^ (*MARK:X)+ +10 ^^ b+ Latest Mark: X+ +11 ^ ^ c+ +12 ^ ^+ 0: abc+.sp+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 "" is output.+.P+The callout function in \fBpcretest\fP returns zero (carry on matching) by+default, but you can use a \eC item in a data line (as described above) to+change this and other parameters of the callout.+.P+Inserting callouts can be helpful when using \fBpcretest\fP to check+complicated regular expressions. For further information about callouts, see+the+.\" HREF+\fBpcrecallout\fP+.\"+documentation.+.+.+.+.SH "NON-PRINTING CHARACTERS"+.rs+.sp+When \fBpcretest\fP 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.+.P+When \fBpcretest\fP 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 \fB/L\fP modifier). In this case, the \fBisprint()\fP+function to distinguish printing and non-printing characters.+.+.+.+.SH "SAVING AND RELOADING COMPILED PATTERNS"+.rs+.sp+The facilities described in this section are not available when the POSIX+interface to PCRE is being used, that is, when the \fB/P\fP pattern modifier is+specified.+.P+When the POSIX interface is not in use, you can cause \fBpcretest\fP to write a+compiled pattern to a file, by following the modifiers with > and a file name.+For example:+.sp+ /pattern/im >/some/file+.sp+See the+.\" HREF+\fBpcreprecompile\fP+.\"+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.+.P+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 second 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, \fBpcretest\fP expects to read a new pattern.+.P+A saved pattern can be reloaded into \fBpcretest\fP 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 \fBpcretest\fP will+interpret the line as a pattern delimited by < characters. For example:+.sp+ re>