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diff --git a/srclib/pcre/doc/pcretest.html b/srclib/pcre/doc/pcretest.html new file mode 100644 index 0000000000..918e6dec2b --- /dev/null +++ b/srclib/pcre/doc/pcretest.html @@ -0,0 +1,369 @@ +<HTML> +<HEAD> +<TITLE>pcretest specification</TITLE> +</HEAD> +<body bgcolor="#FFFFFF" text="#00005A"> +<H1>pcretest specification</H1> +This HTML document has been generated automatically from the original man page. +If there is any nonsense in it, please consult the man page in case the +conversion went wrong. +<UL> +<LI><A NAME="TOC1" HREF="#SEC1">NAME</A> +<LI><A NAME="TOC2" HREF="#SEC2">SYNOPSIS</A> +<LI><A NAME="TOC3" HREF="#SEC3">OPTIONS</A> +<LI><A NAME="TOC4" HREF="#SEC4">DESCRIPTION</A> +<LI><A NAME="TOC5" HREF="#SEC5">PATTERN MODIFIERS</A> +<LI><A NAME="TOC6" HREF="#SEC6">DATA LINES</A> +<LI><A NAME="TOC7" HREF="#SEC7">OUTPUT FROM PCRETEST</A> +<LI><A NAME="TOC8" HREF="#SEC8">AUTHOR</A> +</UL> +<LI><A NAME="SEC1" HREF="#TOC1">NAME</A> +<P> +pcretest - a program for testing Perl-compatible regular expressions. +</P> +<LI><A NAME="SEC2" HREF="#TOC1">SYNOPSIS</A> +<P> +<B>pcretest [-d] [-i] [-m] [-o osize] [-p] [-t] [source] [destination]</B> +</P> +<P> +<B>pcretest</B> 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 <B>pcre</B> man page. +</P> +<LI><A NAME="SEC3" HREF="#TOC1">OPTIONS</A> +<P> +<B>-d</B> +Behave as if each regex had the <B>/D</B> modifier (see below); the internal +form is output after compilation. +</P> +<P> +<B>-i</B> +Behave as if each regex had the <B>/I</B> modifier; information about the +compiled pattern is given after compilation. +</P> +<P> +<B>-m</B> +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, <B>-s</B> is a synonym for <B>-m</B>. +</P> +<P> +<B>-o</B> <I>osize</I> +Set the number of elements in the output vector that is used when calling PCRE +to be <I>osize</I>. The default value is 45, which is enough for 14 capturing +subexpressions. The vector size can be changed for individual matching calls by +including \O in the data line (see below). +</P> +<P> +<B>-p</B> +Behave as if each regex has <B>/P</B> modifier; the POSIX wrapper API is used +to call PCRE. None of the other options has any effect when <B>-p</B> is set. +</P> +<P> +<B>-t</B> +Run each compile, study, and match 20000 times with a timer, and output +resulting time per compile or match (in milliseconds). Do not set <B>-t</B> with +<B>-m</B>, because you will then get the size output 20000 times and the timing +will be distorted. +</P> +<LI><A NAME="SEC4" HREF="#TOC1">DESCRIPTION</A> +<P> +If <B>pcretest</B> 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> +<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 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 +</P> +<P> +<PRE> + /(a|bc)x+yz/ +</PRE> +</P> +<P> +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 +</P> +<P> +<PRE> + /abc\/def/ +</PRE> +</P> +<P> +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 +example, +</P> +<P> +<PRE> + /abc/\ +</PRE> +</P> +<P> +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 +</P> +<P> +<PRE> + /abc\/ +</PRE> +</P> +<P> +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. +</P> +<LI><A NAME="SEC5" HREF="#TOC1">PATTERN MODIFIERS</A> +<P> +The pattern may be followed by <B>i</B>, <B>m</B>, <B>s</B>, or <B>x</B> to set the +PCRE_CASELESS, PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options, +respectively. For example: +</P> +<P> +<PRE> + /caseless/i +</PRE> +</P> +<P> +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: +<B>/A</B>, <B>/E</B>, and <B>/X</B> set PCRE_ANCHORED, PCRE_DOLLAR_ENDONLY, and +PCRE_EXTRA respectively. +</P> +<P> +Searching for all possible matches within each subject string can be requested +by the <B>/g</B> or <B>/G</B> modifier. After finding a match, PCRE is called +again to search the remainder of the subject string. The difference between +<B>/g</B> and <B>/G</B> is that the former uses the <I>startoffset</I> argument to +<B>pcre_exec()</B> 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). +</P> +<P> +If any call to <B>pcre_exec()</B> in a <B>/g</B> or <B>/G</B> 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 +<B>/g</B> modifier or the <B>split()</B> function. +</P> +<P> +There are a number of other modifiers for controlling the way <B>pcretest</B> +operates. +</P> +<P> +The <B>/+</B> 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. +</P> +<P> +The <B>/L</B> modifier must be followed directly by the name of a locale, for +example, +</P> +<P> +<PRE> + /pattern/Lfr +</PRE> +</P> +<P> +For this reason, it must be the last modifier letter. The given locale is set, +<B>pcre_maketables()</B> is called to build a set of character tables for the +locale, and this is then passed to <B>pcre_compile()</B> when compiling the +regular expression. Without an <B>/L</B> modifier, NULL is passed as the tables +pointer; that is, <B>/L</B> applies only to the expression on which it appears. +</P> +<P> +The <B>/I</B> modifier requests that <B>pcretest</B> output information about the +compiled expression (whether it is anchored, has a fixed first character, and +so on). It does this by calling <B>pcre_fullinfo()</B> after compiling an +expression, and outputting the information it gets back. If the pattern is +studied, the results of that are also output. +</P> +<P> +The <B>/D</B> modifier is a PCRE debugging feature, which also assumes <B>/I</B>. +It causes the internal form of compiled regular expressions to be output after +compilation. +</P> +<P> +The <B>/S</B> modifier causes <B>pcre_study()</B> to be called after the +expression has been compiled, and the results used when the expression is +matched. +</P> +<P> +The <B>/M</B> modifier causes the size of memory block used to hold the compiled +pattern to be output. +</P> +<P> +The <B>/P</B> modifier causes <B>pcretest</B> to call PCRE via the POSIX wrapper +API rather than its native API. When this is done, all other modifiers except +<B>/i</B>, <B>/m</B>, and <B>/+</B> are ignored. REG_ICASE is set if <B>/i</B> is +present, and REG_NEWLINE is set if <B>/m</B> is present. The wrapper functions +force PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless REG_NEWLINE is set. +</P> +<P> +The <B>/8</B> modifier causes <B>pcretest</B> to call PCRE with the PCRE_UTF8 +option set. This turns on the (currently incomplete) support for UTF-8 +character handling in PCRE, provided 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. +</P> +<LI><A NAME="SEC6" HREF="#TOC1">DATA LINES</A> +<P> +Before each data line is passed to <B>pcre_exec()</B>, leading and trailing +whitespace is removed, and it is then scanned for \ escapes. The following are +recognized: +</P> +<P> +<PRE> + \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 +</PRE> +</P> +<P> +<PRE> + \A pass the PCRE_ANCHORED option to <B>pcre_exec()</B> + \B pass the PCRE_NOTBOL option to <B>pcre_exec()</B> + \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 <B>pcre_exec()</B> + \Odd set the size of the output vector passed to + <B>pcre_exec()</B> to dd (any number of decimal + digits) + \Z pass the PCRE_NOTEOL option to <B>pcre_exec()</B> +</PRE> +</P> +<P> +When \O is used, it may be higher or lower than the size set by the <B>-O</B> +option (or defaulted to 45); \O applies only to the call of <B>pcre_exec()</B> +for the line in which it appears. +</P> +<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> +<P> +If <B>/P</B> was present on the regex, causing the POSIX wrapper API to be used, +only <B>\B</B>, and <B>\Z</B> have any effect, causing REG_NOTBOL and REG_NOTEOL +to be passed to <B>regexec()</B> respectively. +</P> +<P> +The use of \x{hh...} to represent UTF-8 characters is not dependent on the use +of the <B>/8</B> 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. +</P> +<LI><A NAME="SEC7" HREF="#TOC1">OUTPUT FROM PCRETEST</A> +<P> +When a match succeeds, pcretest outputs the list of captured substrings that +<B>pcre_exec()</B> returns, starting with number 0 for the string that matched +the whole pattern. Here is an example of an interactive pcretest run. +</P> +<P> +<PRE> + $ pcretest + PCRE version 2.06 08-Jun-1999 +</PRE> +</P> +<P> +<PRE> + re> /^abc(\d+)/ + data> abc123 + 0: abc123 + 1: 123 + data> xyz + No match +</PRE> +</P> +<P> +If the strings contain any non-printing characters, they are output as \0x +escapes, or as \x{...} escapes if the <B>/8</B> modifier was present on the +pattern. If the pattern has the <B>/+</B> modifier, then the output for +substring 0 is followed by the the rest of the subject string, identified by +"0+" like this: +</P> +<P> +<PRE> + re> /cat/+ + data> cataract + 0: cat + 0+ aract +</PRE> +</P> +<P> +If the pattern has the <B>/g</B> or <B>/G</B> modifier, the results of successive +matching attempts are output in sequence, like this: +</P> +<P> +<PRE> + re> /\Bi(\w\w)/g + data> Mississippi + 0: iss + 1: ss + 0: iss + 1: ss + 0: ipp + 1: pp +</PRE> +</P> +<P> +"No match" is output only if the first match attempt fails. +</P> +<P> +If any of the sequences <B>\C</B>, <B>\G</B>, or <B>\L</B> 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 <B>\C</B> and <B>\G</B>. +</P> +<P> +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. +</P> +<LI><A NAME="SEC8" HREF="#TOC1">AUTHOR</A> +<P> +Philip Hazel <ph10@cam.ac.uk> +<BR> +University Computing Service, +<BR> +New Museums Site, +<BR> +Cambridge CB2 3QG, England. +<BR> +Phone: +44 1223 334714 +</P> +<P> +Last updated: 15 August 2001 +<BR> +Copyright (c) 1997-2001 University of Cambridge. |