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+<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>&#60;stdio.h&#62;</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. As soon as one pattern matches
+(or fails to match when <b>-v</b> is used), no further patterns are considered.
+</P>
+<P>
+When <b>--only-matching</b>, <b>--file-offsets</b>, or <b>--line-offsets</b>
+is used, the output is the part of the line that matched (either shown
+literally, or as an offset). In this case, 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. However, patterns that follow the one that matched are not tried on the
+earlier part of the line.
+</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 part of a line that matched
+a pattern should be coloured in the output. The value may be "never" (the
+default), "always", or "auto". In the latter case, colouring happens only if
+the standard output is connected to a terminal. The colour 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 and a space; for context lines, a
+hyphen separator is used. If a line number is also being output, it follows the
+file name without a space.
+</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 and a space; for context lines, a hyphen
+separator is used. If a line number is also being output, it follows the file
+name without a space.
+</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
+and a space for matching lines or a hyphen and a space 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: 08 March 2008
+<br>
+Copyright &copy; 1997-2008 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>