534 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
			
		
		
	
	
			534 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
| <html>
 | |
| <head>
 | |
| <title>pcregrep specification</title>
 | |
| </head>
 | |
| <body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
 | |
| <h1>pcregrep man page</h1>
 | |
| <p>
 | |
| Return to the <a href="index.html">PCRE index page</a>.
 | |
| </p>
 | |
| <p>
 | |
| This page is part of the PCRE HTML documentation. It was 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">DESCRIPTION</a>
 | |
| <li><a name="TOC3" href="#SEC3">SUPPORT FOR COMPRESSED FILES</a>
 | |
| <li><a name="TOC4" href="#SEC4">OPTIONS</a>
 | |
| <li><a name="TOC5" href="#SEC5">ENVIRONMENT VARIABLES</a>
 | |
| <li><a name="TOC6" href="#SEC6">NEWLINES</a>
 | |
| <li><a name="TOC7" href="#SEC7">OPTIONS COMPATIBILITY</a>
 | |
| <li><a name="TOC8" href="#SEC8">OPTIONS WITH DATA</a>
 | |
| <li><a name="TOC9" href="#SEC9">MATCHING ERRORS</a>
 | |
| <li><a name="TOC10" href="#SEC10">DIAGNOSTICS</a>
 | |
| <li><a name="TOC11" href="#SEC11">SEE ALSO</a>
 | |
| <li><a name="TOC12" href="#SEC12">AUTHOR</a>
 | |
| <li><a name="TOC13" href="#SEC13">REVISION</a>
 | |
| </ul>
 | |
| <br><a name="SEC1" href="#TOC1">SYNOPSIS</a><br>
 | |
| <P>
 | |
| <b>pcregrep [options] [long options] [pattern] [path1 path2 ...]</b>
 | |
| </P>
 | |
| <br><a name="SEC2" href="#TOC1">DESCRIPTION</a><br>
 | |
| <P>
 | |
| <b>pcregrep</b> searches files for character patterns, in the same way as other
 | |
| grep commands do, but it uses the PCRE regular expression library to support
 | |
| patterns that are compatible with the regular expressions of Perl 5. See
 | |
| <a href="pcrepattern.html"><b>pcrepattern</b>(3)</a>
 | |
| for a full description of syntax and semantics of the regular expressions
 | |
| that PCRE supports.
 | |
| </P>
 | |
| <P>
 | |
| Patterns, whether supplied on the command line or in a separate file, are given
 | |
| without delimiters. For example:
 | |
| <pre>
 | |
|   pcregrep Thursday /etc/motd
 | |
| </pre>
 | |
| If you attempt to use delimiters (for example, by surrounding a pattern with
 | |
| slashes, as is common in Perl scripts), they are interpreted as part of the
 | |
| pattern. Quotes can of course be used to delimit patterns on the command line
 | |
| because they are interpreted by the shell, and indeed they are required if a
 | |
| pattern contains white space or shell metacharacters.
 | |
| </P>
 | |
| <P>
 | |
| The first argument that follows any option settings is treated as the single
 | |
| pattern to be matched when neither <b>-e</b> nor <b>-f</b> is present.
 | |
| Conversely, when one or both of these options are used to specify patterns, all
 | |
| arguments are treated as path names. At least one of <b>-e</b>, <b>-f</b>, or an
 | |
| argument pattern must be provided.
 | |
| </P>
 | |
| <P>
 | |
| If no files are specified, <b>pcregrep</b> reads the standard input. The
 | |
| standard input can also be referenced by a name consisting of a single hyphen.
 | |
| For example:
 | |
| <pre>
 | |
|   pcregrep some-pattern /file1 - /file3
 | |
| </pre>
 | |
| By default, each line that matches a pattern is copied to the standard
 | |
| output, and if there is more than one file, the file name is output at the
 | |
| start of each line, followed by a colon. However, there are options that can
 | |
| change how <b>pcregrep</b> behaves. In particular, the <b>-M</b> option makes it
 | |
| possible to search for patterns that span line boundaries. What defines a line
 | |
| boundary is controlled by the <b>-N</b> (<b>--newline</b>) option.
 | |
| </P>
 | |
| <P>
 | |
| Patterns are limited to 8K or BUFSIZ characters, whichever is the greater.
 | |
| BUFSIZ is defined in <b><stdio.h></b>. When there is more than one pattern
 | |
| (specified by the use of <b>-e</b> and/or <b>-f</b>), each pattern is applied to
 | |
| each line in the order in which they are defined, except that all the <b>-e</b>
 | |
| patterns are tried before the <b>-f</b> patterns.
 | |
| </P>
 | |
| <P>
 | |
| By default, as soon as one pattern matches (or fails to match when <b>-v</b> is
 | |
| used), no further patterns are considered. However, if <b>--colour</b> (or
 | |
| <b>--color</b>) is used to colour the matching substrings, or if
 | |
| <b>--only-matching</b>, <b>--file-offsets</b>, or <b>--line-offsets</b> is used to
 | |
| output only the part of the line that matched (either shown literally, or as an
 | |
| offset), scanning resumes immediately following the match, so that further
 | |
| matches on the same line can be found. If there are multiple patterns, they are
 | |
| all tried on the remainder of the line, but patterns that follow the one that
 | |
| matched are not tried on the earlier part of the line.
 | |
| </P>
 | |
| <P>
 | |
| This is the same behaviour as GNU grep, but it does mean that the order in
 | |
| which multiple patterns are specified can affect the output when one of the
 | |
| above options is used.
 | |
| </P>
 | |
| <P>
 | |
| Patterns that can match an empty string are accepted, but empty string
 | |
| matches are not recognized. An example is the pattern "(super)?(man)?", in
 | |
| which all components are optional. This pattern finds all occurrences of both
 | |
| "super" and "man"; the output differs from matching with "super|man" when only
 | |
| the matching substrings are being shown.
 | |
| </P>
 | |
| <P>
 | |
| If the <b>LC_ALL</b> or <b>LC_CTYPE</b> environment variable is set,
 | |
| <b>pcregrep</b> uses the value to set a locale when calling the PCRE library.
 | |
| The <b>--locale</b> option can be used to override this.
 | |
| </P>
 | |
| <br><a name="SEC3" href="#TOC1">SUPPORT FOR COMPRESSED FILES</a><br>
 | |
| <P>
 | |
| It is possible to compile <b>pcregrep</b> so that it uses <b>libz</b> or
 | |
| <b>libbz2</b> to read files whose names end in <b>.gz</b> or <b>.bz2</b>,
 | |
| respectively. You can find out whether your binary has support for one or both
 | |
| of these file types by running it with the <b>--help</b> option. If the
 | |
| appropriate support is not present, files are treated as plain text. The
 | |
| standard input is always so treated.
 | |
| </P>
 | |
| <br><a name="SEC4" href="#TOC1">OPTIONS</a><br>
 | |
| <P>
 | |
| <b>--</b>
 | |
| This terminate the list of options. It is useful if the next item on the
 | |
| command line starts with a hyphen but is not an option. This allows for the
 | |
| processing of patterns and filenames that start with hyphens.
 | |
| </P>
 | |
| <P>
 | |
| <b>-A</b> <i>number</i>, <b>--after-context=</b><i>number</i>
 | |
| Output <i>number</i> lines of context after each matching line. If filenames
 | |
| and/or line numbers are being output, a hyphen separator is used instead of a
 | |
| colon for the context lines. A line containing "--" is output between each
 | |
| group of lines, unless they are in fact contiguous in the input file. The value
 | |
| of <i>number</i> is expected to be relatively small. However, <b>pcregrep</b>
 | |
| guarantees to have up to 8K of following text available for context output.
 | |
| </P>
 | |
| <P>
 | |
| <b>-B</b> <i>number</i>, <b>--before-context=</b><i>number</i>
 | |
| Output <i>number</i> lines of context before each matching line. If filenames
 | |
| and/or line numbers are being output, a hyphen separator is used instead of a
 | |
| colon for the context lines. A line containing "--" is output between each
 | |
| group of lines, unless they are in fact contiguous in the input file. The value
 | |
| of <i>number</i> is expected to be relatively small. However, <b>pcregrep</b>
 | |
| guarantees to have up to 8K of preceding text available for context output.
 | |
| </P>
 | |
| <P>
 | |
| <b>-C</b> <i>number</i>, <b>--context=</b><i>number</i>
 | |
| Output <i>number</i> lines of context both before and after each matching line.
 | |
| This is equivalent to setting both <b>-A</b> and <b>-B</b> to the same value.
 | |
| </P>
 | |
| <P>
 | |
| <b>-c</b>, <b>--count</b>
 | |
| Do not output individual lines; instead just output a count of the number of
 | |
| lines that would otherwise have been output. If several files are given, a
 | |
| count is output for each of them. In this mode, the <b>-A</b>, <b>-B</b>, and
 | |
| <b>-C</b> options are ignored.
 | |
| </P>
 | |
| <P>
 | |
| <b>--colour</b>, <b>--color</b>
 | |
| If this option is given without any data, it is equivalent to "--colour=auto".
 | |
| If data is required, it must be given in the same shell item, separated by an
 | |
| equals sign.
 | |
| </P>
 | |
| <P>
 | |
| <b>--colour=</b><i>value</i>, <b>--color=</b><i>value</i>
 | |
| This option specifies under what circumstances the parts of a line that matched
 | |
| a pattern should be coloured in the output. By default, the output is not
 | |
| coloured. The value (which is optional, see above) may be "never", "always", or
 | |
| "auto". In the latter case, colouring happens only if the standard output is
 | |
| connected to a terminal. More resources are used when colouring is enabled,
 | |
| because <b>pcregrep</b> has to search for all possible matches in a line, not
 | |
| just one, in order to colour them all.
 | |
| </P>
 | |
| <P>
 | |
| The colour that is used can be specified by setting the environment variable
 | |
| PCREGREP_COLOUR or PCREGREP_COLOR. The value of this variable should be a
 | |
| string of two numbers, separated by a semicolon. They are copied directly into
 | |
| the control string for setting colour on a terminal, so it is your
 | |
| responsibility to ensure that they make sense. If neither of the environment
 | |
| variables is set, the default is "1;31", which gives red.
 | |
| </P>
 | |
| <P>
 | |
| <b>-D</b> <i>action</i>, <b>--devices=</b><i>action</i>
 | |
| If an input path is not a regular file or a directory, "action" specifies how
 | |
| it is to be processed. Valid values are "read" (the default) or "skip"
 | |
| (silently skip the path).
 | |
| </P>
 | |
| <P>
 | |
| <b>-d</b> <i>action</i>, <b>--directories=</b><i>action</i>
 | |
| If an input path is a directory, "action" specifies how it is to be processed.
 | |
| Valid values are "read" (the default), "recurse" (equivalent to the <b>-r</b>
 | |
| option), or "skip" (silently skip the path). In the default case, directories
 | |
| are read as if they were ordinary files. In some operating systems the effect
 | |
| of reading a directory like this is an immediate end-of-file.
 | |
| </P>
 | |
| <P>
 | |
| <b>-e</b> <i>pattern</i>, <b>--regex=</b><i>pattern</i>, <b>--regexp=</b><i>pattern</i>
 | |
| Specify a pattern to be matched. This option can be used multiple times in
 | |
| order to specify several patterns. It can also be used as a way of specifying a
 | |
| single pattern that starts with a hyphen. When <b>-e</b> is used, no argument
 | |
| pattern is taken from the command line; all arguments are treated as file
 | |
| names. There is an overall maximum of 100 patterns. They are applied to each
 | |
| line in the order in which they are defined until one matches (or fails to
 | |
| match if <b>-v</b> is used). If <b>-f</b> is used with <b>-e</b>, the command line
 | |
| patterns are matched first, followed by the patterns from the file, independent
 | |
| of the order in which these options are specified. Note that multiple use of
 | |
| <b>-e</b> is not the same as a single pattern with alternatives. For example,
 | |
| X|Y finds the first character in a line that is X or Y, whereas if the two
 | |
| patterns are given separately, <b>pcregrep</b> finds X if it is present, even if
 | |
| it follows Y in the line. It finds Y only if there is no X in the line. This
 | |
| really matters only if you are using <b>-o</b> to show the part(s) of the line
 | |
| that matched.
 | |
| </P>
 | |
| <P>
 | |
| <b>--exclude</b>=<i>pattern</i>
 | |
| When <b>pcregrep</b> is searching the files in a directory as a consequence of
 | |
| the <b>-r</b> (recursive search) option, any regular files whose names match the
 | |
| pattern are excluded. Subdirectories are not excluded by this option; they are
 | |
| searched recursively, subject to the <b>--exclude_dir</b> and
 | |
| <b>--include_dir</b> options. The pattern is a PCRE regular expression, and is
 | |
| matched against the final component of the file name (not the entire path). If
 | |
| a file name matches both <b>--include</b> and <b>--exclude</b>, it is excluded.
 | |
| There is no short form for this option.
 | |
| </P>
 | |
| <P>
 | |
| <b>--exclude_dir</b>=<i>pattern</i>
 | |
| When <b>pcregrep</b> is searching the contents of a directory as a consequence
 | |
| of the <b>-r</b> (recursive search) option, any subdirectories whose names match
 | |
| the pattern are excluded. (Note that the \fP--exclude\fP option does not affect
 | |
| subdirectories.) The pattern is a PCRE regular expression, and is matched
 | |
| against the final component of the name (not the entire path). If a
 | |
| subdirectory name matches both <b>--include_dir</b> and <b>--exclude_dir</b>, it
 | |
| is excluded. There is no short form for this option.
 | |
| </P>
 | |
| <P>
 | |
| <b>-F</b>, <b>--fixed-strings</b>
 | |
| Interpret each pattern as a list of fixed strings, separated by newlines,
 | |
| instead of as a regular expression. The <b>-w</b> (match as a word) and <b>-x</b>
 | |
| (match whole line) options can be used with <b>-F</b>. They apply to each of the
 | |
| fixed strings. A line is selected if any of the fixed strings are found in it
 | |
| (subject to <b>-w</b> or <b>-x</b>, if present).
 | |
| </P>
 | |
| <P>
 | |
| <b>-f</b> <i>filename</i>, <b>--file=</b><i>filename</i>
 | |
| Read a number of patterns from the file, one per line, and match them against
 | |
| each line of input. A data line is output if any of the patterns match it. The
 | |
| filename can be given as "-" to refer to the standard input. When <b>-f</b> is
 | |
| used, patterns specified on the command line using <b>-e</b> may also be
 | |
| present; they are tested before the file's patterns. However, no other pattern
 | |
| is taken from the command line; all arguments are treated as file names. There
 | |
| is an overall maximum of 100 patterns. Trailing white space is removed from
 | |
| each line, and blank lines are ignored. An empty file contains no patterns and
 | |
| therefore matches nothing. See also the comments about multiple patterns versus
 | |
| a single pattern with alternatives in the description of <b>-e</b> above.
 | |
| </P>
 | |
| <P>
 | |
| <b>--file-offsets</b>
 | |
| Instead of showing lines or parts of lines that match, show each match as an
 | |
| offset from the start of the file and a length, separated by a comma. In this
 | |
| mode, no context is shown. That is, the <b>-A</b>, <b>-B</b>, and <b>-C</b>
 | |
| options are ignored. If there is more than one match in a line, each of them is
 | |
| shown separately. This option is mutually exclusive with <b>--line-offsets</b>
 | |
| and <b>--only-matching</b>.
 | |
| </P>
 | |
| <P>
 | |
| <b>-H</b>, <b>--with-filename</b>
 | |
| Force the inclusion of the filename at the start of output lines when searching
 | |
| a single file. By default, the filename is not shown in this case. For matching
 | |
| lines, the filename is followed by a colon; for context lines, a hyphen
 | |
| separator is used. If a line number is also being output, it follows the file
 | |
| name.
 | |
| </P>
 | |
| <P>
 | |
| <b>-h</b>, <b>--no-filename</b>
 | |
| Suppress the output filenames when searching multiple files. By default,
 | |
| filenames are shown when multiple files are searched. For matching lines, the
 | |
| filename is followed by a colon; for context lines, a hyphen separator is used.
 | |
| If a line number is also being output, it follows the file name.
 | |
| </P>
 | |
| <P>
 | |
| <b>--help</b>
 | |
| Output a help message, giving brief details of the command options and file
 | |
| type support, and then exit.
 | |
| </P>
 | |
| <P>
 | |
| <b>-i</b>, <b>--ignore-case</b>
 | |
| Ignore upper/lower case distinctions during comparisons.
 | |
| </P>
 | |
| <P>
 | |
| <b>--include</b>=<i>pattern</i>
 | |
| When <b>pcregrep</b> is searching the files in a directory as a consequence of
 | |
| the <b>-r</b> (recursive search) option, only those regular files whose names
 | |
| match the pattern are included. Subdirectories are always included and searched
 | |
| recursively, subject to the \fP--include_dir\fP and <b>--exclude_dir</b>
 | |
| options. The pattern is a PCRE regular expression, and is matched against the
 | |
| final component of the file name (not the entire path). If a file name matches
 | |
| both <b>--include</b> and <b>--exclude</b>, it is excluded. There is no short
 | |
| form for this option.
 | |
| </P>
 | |
| <P>
 | |
| <b>--include_dir</b>=<i>pattern</i>
 | |
| When <b>pcregrep</b> is searching the contents of a directory as a consequence
 | |
| of the <b>-r</b> (recursive search) option, only those subdirectories whose
 | |
| names match the pattern are included. (Note that the <b>--include</b> option
 | |
| does not affect subdirectories.) The pattern is a PCRE regular expression, and
 | |
| is matched against the final component of the name (not the entire path). If a
 | |
| subdirectory name matches both <b>--include_dir</b> and <b>--exclude_dir</b>, it
 | |
| is excluded. There is no short form for this option.
 | |
| </P>
 | |
| <P>
 | |
| <b>-L</b>, <b>--files-without-match</b>
 | |
| Instead of outputting lines from the files, just output the names of the files
 | |
| that do not contain any lines that would have been output. Each file name is
 | |
| output once, on a separate line.
 | |
| </P>
 | |
| <P>
 | |
| <b>-l</b>, <b>--files-with-matches</b>
 | |
| Instead of outputting lines from the files, just output the names of the files
 | |
| containing lines that would have been output. Each file name is output
 | |
| once, on a separate line. Searching stops as soon as a matching line is found
 | |
| in a file.
 | |
| </P>
 | |
| <P>
 | |
| <b>--label</b>=<i>name</i>
 | |
| This option supplies a name to be used for the standard input when file names
 | |
| are being output. If not supplied, "(standard input)" is used. There is no
 | |
| short form for this option.
 | |
| </P>
 | |
| <P>
 | |
| <b>--line-offsets</b>
 | |
| Instead of showing lines or parts of lines that match, show each match as a
 | |
| line number, the offset from the start of the line, and a length. The line
 | |
| number is terminated by a colon (as usual; see the <b>-n</b> option), and the
 | |
| offset and length are separated by a comma. In this mode, no context is shown.
 | |
| That is, the <b>-A</b>, <b>-B</b>, and <b>-C</b> options are ignored. If there is
 | |
| more than one match in a line, each of them is shown separately. This option is
 | |
| mutually exclusive with <b>--file-offsets</b> and <b>--only-matching</b>.
 | |
| </P>
 | |
| <P>
 | |
| <b>--locale</b>=<i>locale-name</i>
 | |
| This option specifies a locale to be used for pattern matching. It overrides
 | |
| the value in the <b>LC_ALL</b> or <b>LC_CTYPE</b> environment variables. If no
 | |
| locale is specified, the PCRE library's default (usually the "C" locale) is
 | |
| used. There is no short form for this option.
 | |
| </P>
 | |
| <P>
 | |
| <b>-M</b>, <b>--multiline</b>
 | |
| Allow patterns to match more than one line. When this option is given, patterns
 | |
| may usefully contain literal newline characters and internal occurrences of ^
 | |
| and $ characters. The output for any one match may consist of more than one
 | |
| line. When this option is set, the PCRE library is called in "multiline" mode.
 | |
| There is a limit to the number of lines that can be matched, imposed by the way
 | |
| that <b>pcregrep</b> buffers the input file as it scans it. However,
 | |
| <b>pcregrep</b> ensures that at least 8K characters or the rest of the document
 | |
| (whichever is the shorter) are available for forward matching, and similarly
 | |
| the previous 8K characters (or all the previous characters, if fewer than 8K)
 | |
| are guaranteed to be available for lookbehind assertions.
 | |
| </P>
 | |
| <P>
 | |
| <b>-N</b> <i>newline-type</i>, <b>--newline=</b><i>newline-type</i>
 | |
| The PCRE library supports five different conventions for indicating
 | |
| the ends of lines. They are the single-character sequences CR (carriage return)
 | |
| and LF (linefeed), the two-character sequence CRLF, an "anycrlf" convention,
 | |
| which recognizes any of the preceding three types, and an "any" convention, in
 | |
| which any Unicode line ending sequence is assumed to end a line. The Unicode
 | |
| sequences are the three just mentioned, plus VT (vertical tab, U+000B), FF
 | |
| (formfeed, U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and
 | |
| PS (paragraph separator, U+2029).
 | |
| <br>
 | |
| <br>
 | |
| When the PCRE library is built, a default line-ending sequence is specified.
 | |
| This is normally the standard sequence for the operating system. Unless
 | |
| otherwise specified by this option, <b>pcregrep</b> uses the library's default.
 | |
| The possible values for this option are CR, LF, CRLF, ANYCRLF, or ANY. This
 | |
| makes it possible to use <b>pcregrep</b> on files that have come from other
 | |
| environments without having to modify their line endings. If the data that is
 | |
| being scanned does not agree with the convention set by this option,
 | |
| <b>pcregrep</b> may behave in strange ways.
 | |
| </P>
 | |
| <P>
 | |
| <b>-n</b>, <b>--line-number</b>
 | |
| Precede each output line by its line number in the file, followed by a colon
 | |
| for matching lines or a hyphen for context lines. If the filename is also being
 | |
| output, it precedes the line number. This option is forced if
 | |
| <b>--line-offsets</b> is used.
 | |
| </P>
 | |
| <P>
 | |
| <b>-o</b>, <b>--only-matching</b>
 | |
| Show only the part of the line that matched a pattern. In this mode, no
 | |
| context is shown. That is, the <b>-A</b>, <b>-B</b>, and <b>-C</b> options are
 | |
| ignored. If there is more than one match in a line, each of them is shown
 | |
| separately. If <b>-o</b> is combined with <b>-v</b> (invert the sense of the
 | |
| match to find non-matching lines), no output is generated, but the return code
 | |
| is set appropriately. This option is mutually exclusive with
 | |
| <b>--file-offsets</b> and <b>--line-offsets</b>.
 | |
| </P>
 | |
| <P>
 | |
| <b>-q</b>, <b>--quiet</b>
 | |
| Work quietly, that is, display nothing except error messages. The exit
 | |
| status indicates whether or not any matches were found.
 | |
| </P>
 | |
| <P>
 | |
| <b>-r</b>, <b>--recursive</b>
 | |
| If any given path is a directory, recursively scan the files it contains,
 | |
| taking note of any <b>--include</b> and <b>--exclude</b> settings. By default, a
 | |
| directory is read as a normal file; in some operating systems this gives an
 | |
| immediate end-of-file. This option is a shorthand for setting the <b>-d</b>
 | |
| option to "recurse".
 | |
| </P>
 | |
| <P>
 | |
| <b>-s</b>, <b>--no-messages</b>
 | |
| Suppress error messages about non-existent or unreadable files. Such files are
 | |
| quietly skipped. However, the return code is still 2, even if matches were
 | |
| found in other files.
 | |
| </P>
 | |
| <P>
 | |
| <b>-u</b>, <b>--utf-8</b>
 | |
| Operate in UTF-8 mode. This option is available only if PCRE has been compiled
 | |
| with UTF-8 support. Both patterns and subject lines must be valid strings of
 | |
| UTF-8 characters.
 | |
| </P>
 | |
| <P>
 | |
| <b>-V</b>, <b>--version</b>
 | |
| Write the version numbers of <b>pcregrep</b> and the PCRE library that is being
 | |
| used to the standard error stream.
 | |
| </P>
 | |
| <P>
 | |
| <b>-v</b>, <b>--invert-match</b>
 | |
| Invert the sense of the match, so that lines which do <i>not</i> match any of
 | |
| the patterns are the ones that are found.
 | |
| </P>
 | |
| <P>
 | |
| <b>-w</b>, <b>--word-regex</b>, <b>--word-regexp</b>
 | |
| Force the patterns to match only whole words. This is equivalent to having \b
 | |
| at the start and end of the pattern.
 | |
| </P>
 | |
| <P>
 | |
| <b>-x</b>, <b>--line-regex</b>, <b>--line-regexp</b>
 | |
| Force the patterns to be anchored (each must start matching at the beginning of
 | |
| a line) and in addition, require them to match entire lines. This is
 | |
| equivalent to having ^ and $ characters at the start and end of each
 | |
| alternative branch in every pattern.
 | |
| </P>
 | |
| <br><a name="SEC5" href="#TOC1">ENVIRONMENT VARIABLES</a><br>
 | |
| <P>
 | |
| The environment variables <b>LC_ALL</b> and <b>LC_CTYPE</b> are examined, in that
 | |
| order, for a locale. The first one that is set is used. This can be overridden
 | |
| by the <b>--locale</b> option. If no locale is set, the PCRE library's default
 | |
| (usually the "C" locale) is used.
 | |
| </P>
 | |
| <br><a name="SEC6" href="#TOC1">NEWLINES</a><br>
 | |
| <P>
 | |
| The <b>-N</b> (<b>--newline</b>) option allows <b>pcregrep</b> to scan files with
 | |
| different newline conventions from the default. However, the setting of this
 | |
| option does not affect the way in which <b>pcregrep</b> writes information to
 | |
| the standard error and output streams. It uses the string "\n" in C
 | |
| <b>printf()</b> calls to indicate newlines, relying on the C I/O library to
 | |
| convert this to an appropriate sequence if the output is sent to a file.
 | |
| </P>
 | |
| <br><a name="SEC7" href="#TOC1">OPTIONS COMPATIBILITY</a><br>
 | |
| <P>
 | |
| The majority of short and long forms of <b>pcregrep</b>'s options are the same
 | |
| as in the GNU <b>grep</b> program. Any long option of the form
 | |
| <b>--xxx-regexp</b> (GNU terminology) is also available as <b>--xxx-regex</b>
 | |
| (PCRE terminology). However, the <b>--locale</b>, <b>-M</b>, <b>--multiline</b>,
 | |
| <b>-u</b>, and <b>--utf-8</b> options are specific to <b>pcregrep</b>.
 | |
| </P>
 | |
| <br><a name="SEC8" href="#TOC1">OPTIONS WITH DATA</a><br>
 | |
| <P>
 | |
| There are four different ways in which an option with data can be specified.
 | |
| If a short form option is used, the data may follow immediately, or in the next
 | |
| command line item. For example:
 | |
| <pre>
 | |
|   -f/some/file
 | |
|   -f /some/file
 | |
| </pre>
 | |
| If a long form option is used, the data may appear in the same command line
 | |
| item, separated by an equals character, or (with one exception) it may appear
 | |
| in the next command line item. For example:
 | |
| <pre>
 | |
|   --file=/some/file
 | |
|   --file /some/file
 | |
| </pre>
 | |
| Note, however, that if you want to supply a file name beginning with ~ as data
 | |
| in a shell command, and have the shell expand ~ to a home directory, you must
 | |
| separate the file name from the option, because the shell does not treat ~
 | |
| specially unless it is at the start of an item.
 | |
| </P>
 | |
| <P>
 | |
| The exception to the above is the <b>--colour</b> (or <b>--color</b>) option,
 | |
| for which the data is optional. If this option does have data, it must be given
 | |
| in the first form, using an equals character. Otherwise it will be assumed that
 | |
| it has no data.
 | |
| </P>
 | |
| <br><a name="SEC9" href="#TOC1">MATCHING ERRORS</a><br>
 | |
| <P>
 | |
| It is possible to supply a regular expression that takes a very long time to
 | |
| fail to match certain lines. Such patterns normally involve nested indefinite
 | |
| repeats, for example: (a+)*\d when matched against a line of a's with no final
 | |
| digit. The PCRE matching function has a resource limit that causes it to abort
 | |
| in these circumstances. If this happens, <b>pcregrep</b> outputs an error
 | |
| message and the line that caused the problem to the standard error stream. If
 | |
| there are more than 20 such errors, <b>pcregrep</b> gives up.
 | |
| </P>
 | |
| <br><a name="SEC10" href="#TOC1">DIAGNOSTICS</a><br>
 | |
| <P>
 | |
| Exit status is 0 if any matches were found, 1 if no matches were found, and 2
 | |
| for syntax errors and non-existent or inacessible files (even if matches were
 | |
| found in other files) or too many matching errors. Using the <b>-s</b> option to
 | |
| suppress error messages about inaccessble files does not affect the return
 | |
| code.
 | |
| </P>
 | |
| <br><a name="SEC11" href="#TOC1">SEE ALSO</a><br>
 | |
| <P>
 | |
| <b>pcrepattern</b>(3), <b>pcretest</b>(1).
 | |
| </P>
 | |
| <br><a name="SEC12" href="#TOC1">AUTHOR</a><br>
 | |
| <P>
 | |
| Philip Hazel
 | |
| <br>
 | |
| University Computing Service
 | |
| <br>
 | |
| Cambridge CB2 3QH, England.
 | |
| <br>
 | |
| </P>
 | |
| <br><a name="SEC13" href="#TOC1">REVISION</a><br>
 | |
| <P>
 | |
| Last updated: 01 March 2009
 | |
| <br>
 | |
| Copyright © 1997-2009 University of Cambridge.
 | |
| <br>
 | |
| <p>
 | |
| Return to the <a href="index.html">PCRE index page</a>.
 | |
| </p>
 |