diff options
Diffstat (limited to 'external-libs/pcre/doc/html/pcretest.html')
| -rw-r--r-- | external-libs/pcre/doc/html/pcretest.html | 443 |
1 files changed, 443 insertions, 0 deletions
diff --git a/external-libs/pcre/doc/html/pcretest.html b/external-libs/pcre/doc/html/pcretest.html new file mode 100644 index 00000000..2ba9893d --- /dev/null +++ b/external-libs/pcre/doc/html/pcretest.html @@ -0,0 +1,443 @@ +<html> +<head> +<title>pcretest specification</title> +</head> +<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB"> +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.<br> +<ul> +<li><a name="TOC1" href="#SEC1">SYNOPSIS</a> +<li><a name="TOC2" href="#SEC2">OPTIONS</a> +<li><a name="TOC3" href="#SEC3">DESCRIPTION</a> +<li><a name="TOC4" href="#SEC4">PATTERN MODIFIERS</a> +<li><a name="TOC5" href="#SEC5">CALLOUTS</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> +<br><a name="SEC1" href="#TOC1">SYNOPSIS</a><br> +<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 document describes the features of the test program; for +details of the regular expressions themselves, see the +<a href="pcrepattern.html"><b>pcrepattern</b></a> +documentation. For details of PCRE and its options, see the +<a href="pcreapi.html"><b>pcreapi</b></a> +documentation. +</P> +<br><a name="SEC2" href="#TOC1">OPTIONS</a><br> +<P> +<b>-C</b> +Output the version number of the PCRE library, and all available information +about the optional features that are included, and then exit. +</P> +<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 many 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> +<br><a name="SEC3" href="#TOC1">DESCRIPTION</a><br> +<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. +</P> +<P> +Each line is matched separately and independently. If you want to do +multiple-line matches, you have to use the \n escape sequence in a single line +of input to encode the newline characters. The maximum length of data line is +30,000 characters. +</P> +<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-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> +<br><a name="SEC4" href="#TOC1">PATTERN MODIFIERS</a><br> +<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 that set PCRE options that do not correspond to anything in Perl: +<b>/A</b>, <b>/E</b>, <b>/N</b>, <b>/U</b>, and <b>/X</b> set PCRE_ANCHORED, +PCRE_DOLLAR_ENDONLY, PCRE_NO_AUTO_CAPTURE, PCRE_UNGREEDY, 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. If the pattern was studied, the information returned is also +output. +</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 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> +<P> +If the <b>/?</b> modifier is used with <b>/8</b>, it causes <b>pcretest</b> to +call <b>pcre_compile()</b> with the PCRE_NO_UTF8_CHECK option, to suppress the +checking of the string for UTF-8 validity. +</P> +<br><a name="SEC5" href="#TOC1">CALLOUTS</a><br> +<P> +If the pattern contains any callout requests, <b>pcretest</b>'s callout function +will be called. By default, it displays the callout number, and the start and +current positions in the text at the callout time. For example, the output +</P> +<P> +<pre> + --->pqrabcdef + 0 ^ ^ +</PRE> +</P> +<P> +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. The callout function returns zero (carry on matching) by default. +</P> +<P> +Inserting callouts may be helpful when using <b>pcretest</b> to check +complicated regular expressions. For further information about callouts, see +the +<a href="pcrecallout.html"><b>pcrecallout</b></a> +documentation. +</P> +<P> +For testing the PCRE library, additional control of callout behaviour is +available via escape sequences in the data, as described in the following +section. In particular, it is possible to pass in a number as callout data (the +default is zero). If the callout function receives a non-zero number, it +returns that value instead of zero. +</P> +<br><a name="SEC6" href="#TOC1">DATA LINES</a><br> +<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. 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: +</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 character, any number of digits + in UTF-8 mode + \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) + \Cname call pcre_copy_named_substring() for substring + "name" after a successful match (name termin- + ated by next non alphanumeric character) + \C+ show the current captured substrings at callout + time + \C- do not supply a callout function + \C!n return 1 instead of 0 when callout number n is + reached + \C!n!m return 1 instead of 0 when callout number n is + reached for the nth time + \C*n pass the number n (may be negative) as callout + data + \Gdd call pcre_get_substring() for substring dd + after a successful match (any decimal number + less than 32) + \Gname call pcre_get_named_substring() for substring + "name" after a successful match (name termin- + ated by next non-alphanumeric character) + \L call pcre_get_substringlist() after a + successful match + \M discover the minimum MATCH_LIMIT setting + \N pass the PCRE_NOTEMPTY option to <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) + \S output details of memory get/free calls during matching + \Z pass the PCRE_NOTEOL option to <b>pcre_exec()</b> + \? pass the PCRE_NO_UTF8_CHECK option to + <b>pcre_exec()</b> +</PRE> +</P> +<P> +If \M is present, <b>pcretest</b> calls <b>pcre_exec()</b> several times, with +different values in the <i>match_limit</i> field of the <b>pcre_extra</b> data +structure, until it finds the minimum number that is needed for +<b>pcre_exec()</b> to complete. This number is a measure of the amount of +recursion and backtracking that takes place, and checking it out can be +instructive. For most simple matches, the number is quite small, but for +patterns with very large numbers of matching possibilities, it can become large +very quickly with increasing length of subject string. +</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> +<br><a name="SEC7" href="#TOC1">OUTPUT FROM PCRETEST</a><br> +<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 4.00 08-Jan-2003 +</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> +<br><a name="SEC8" href="#TOC1">AUTHOR</a><br> +<P> +Philip Hazel <ph10@cam.ac.uk> +<br> +University Computing Service, +<br> +Cambridge CB2 3QG, England. +</P> +<P> +Last updated: 09 December 2003 +<br> +Copyright © 1997-2003 University of Cambridge. |