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NAME

       pcregrep - a grep with Perl-compatible regular expressions.

SYNOPSIS

       pcregrep   [options]   [long   options]  [pattern]  [path1  path2  ...]
       zpcregrep [options] [long options] [pattern] [file1 file2 ...]

DESCRIPTION


       pcregrep 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  pcresyntax(3)  for  a quick-reference summary of pattern
       syntax, or pcrepattern(3) for a full  description  of  the  syntax  and
       semantics of the regular expressions that PCRE supports.

       Patterns,  whether  supplied on the command line or in a separate file,
       are given without delimiters. For example:

         pcregrep Thursday /etc/motd

       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 quotes are required if a pattern contains white space  or  shell
       metacharacters.

       The  first  argument that follows any option settings is treated as the
       single pattern to be  matched  when  neither  -e  nor  -f  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  -e,
       -f, or an argument pattern must be provided.

       If  no  files  are  specified,  pcregrep  reads the standard input. The
       standard input can also be referenced by a name consisting of a  single
       hyphen.  For example:

         pcregrep some-pattern /file1 - /file3

       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 pcregrep behaves.  In  particular,  the  -M  option
       makes  it  possible  to  search for patterns that span line boundaries.
       What defines a line  boundary  is  controlled  by  the  -N  (--newline)
       option.

       The amount of memory used for buffering files that are being scanned is
       controlled by a parameter that can be set by the --buffer-size  option.
       The  default  value  for  this  parameter is specified when pcregrep is
       built, with the default default being 20K.  A  block  of  memory  three
       times  this  size  is used (to allow for buffering "before" and "after"
       lines). An error occurs if a line overflows the buffer.

       Patterns can be no longer than 8K or BUFSIZ  bytes,  whichever  is  the
       greater.   BUFSIZ  is defined in <stdio.h>. When there is more than one
       pattern (specified by the use of -e and/or -f), each pattern is applied
       to  each  line  in the order in which they are defined, except that all
       the -e patterns are tried before the -f patterns.

       By default, as soon as one pattern matches a line, no further  patterns
       are considered. However, if --colour (or --color) is used to colour the
       matching substrings, or if --only-matching, --file-offsets, or  --line-
       offsets  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.

       This behaviour means that the order  in  which  multiple  patterns  are
       specified  can affect the output when one of the above options is used.
       This is no longer the same behaviour as GNU grep, which now manages  to
       display  earlier  matches  for  later  patterns (as long as there is no
       overlap).

       Patterns that can match an empty string are accepted, but empty  string
       matches   are   never   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.

       If  the  LC_ALL  or LC_CTYPE environment variable is set, pcregrep uses
       the value to set a locale when calling the PCRE library.  The  --locale
       option can be used to override this.

       zpcregrep  is  a  wrapper  script  that allows pcregrep to work on gzip
       compressed files.

SUPPORT FOR COMPRESSED FILES


       It is possible to compile pcregrep so that it uses libz  or  libbz2  to
       read  files  whose names end in .gz or .bz2, respectively. You can find
       out whether your binary has support for one or both of these file types
       by running it with the --help option. If the appropriate support is not
       present, files are treated as plain text. The standard input is  always
       so treated.

BINARY FILES


       By  default,  a  file that contains a binary zero byte within the first
       1024 bytes is identified as a binary file, and is processed  specially.
       (GNU  grep  also  identifies  binary  files  in  this  manner.) See the
       --binary-files option for a means of changing the way binary files  are
       handled.

OPTIONS


       The  order  in  which some of the options appear can affect the output.
       For example, both the -h and -l options affect  the  printing  of  file
       names.  Whichever  comes later in the command line will be the one that
       takes effect. Similarly, except where noted  below,  if  an  option  is
       given  twice,  the  later setting is used. Numerical values for options
       may be followed by K  or  M,  to  signify  multiplication  by  1024  or
       1024*1024 respectively.

       --        This terminates 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.

       -A number, --after-context=number
                 Output number 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 number is expected to be relatively small. However,
                 pcregrep guarantees to  have  up  to  8K  of  following  text
                 available for context output.

       -a, --text
                 Treat  binary  files as text. This is equivalent to --binary-
                 files=text.

       -B number, --before-context=number
                 Output number 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 number is expected to be relatively small. However,
                 pcregrep guarantees to  have  up  to  8K  of  preceding  text
                 available for context output.

       --binary-files=word
                 Specify  how binary files are to be processed. If the word is
                 "binary" (the default),  pattern  matching  is  performed  on
                 binary  files,  but  the  only  output is "Binary file <name>
                 matches" when a match succeeds. If the word is "text",  which
                 is  equivalent  to  the -a or --text option, binary files are
                 processed in the same way as any other file.  In  this  case,
                 when  a  match  succeeds,  the  output may be binary garbage,
                 which can have nasty effects if sent to a  terminal.  If  the
                 word  is  "without-match",  which  is  equivalent  to  the -I
                 option, binary files are  not  processed  at  all;  they  are
                 assumed not to be of interest.

       --buffer-size=number
                 Set  the  parameter that controls how much memory is used for
                 buffering files that are being scanned.

       -C number, --context=number
                 Output number lines of context both  before  and  after  each
                 matching  line.  This is equivalent to setting both -A and -B
                 to the same value.

       -c, --count
                 Do not output individual lines from the files that are  being
                 scanned;  instead  output  the  number  of  lines  that would
                 otherwise have been shown. If  no  lines  are  selected,  the
                 number  zero  is  output.  If  several  files  are  are being
                 scanned, a count is output for each of them. However, if  the
                 --files-with-matches  option  is  also used, only those files
                 whose counts are greater than zero are  listed.  When  -c  is
                 used, the -A, -B, and -C options are ignored.

       --colour, --color
                 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.

       --colour=value, --color=value
                 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 pcregrep has to search for
                 all possible matches in a line, not just  one,  in  order  to
                 colour them all.

                 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.

       -D action, --devices=action
                 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).

       -d action, --directories=action
                 If an input path is a directory, "action" specifies how it is
                 to  be  processed.   Valid  values are "read" (the default in
                 non-Windows environments, for compatibility with  GNU  grep),
                 "recurse"  (equivalent to the -r option), or "skip" (silently
                 skip the path, the default in Windows environments).  In  the
                 "read"  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; in others it
                 may provoke an error.

       -e pattern, --regex=pattern, --regexp=pattern
                 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 -e is used, no argument pattern is
                 taken from the command line; all  arguments  are  treated  as
                 file names. There is no limit to the number of patterns. They
                 are applied to each line in  the  order  in  which  they  are
                 defined until one matches.

                 If  -f is used with -e, the command line patterns are matched
                 first, followed by the patterns from the file(s), independent
                 of  the order in which these options are specified. Note that
                 multiple use of -e 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,  with X first, pcregrep 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 matters only if you are using -o or
                 --colo(u)r to show the part(s) of the line that matched.

       --exclude=pattern
                 Files (but not directories) whose names match the pattern are
                 skipped  without  being processed. This applies to all files,
                 whether listed on the command  line,  obtained  from  --file-
                 list,  or  by  scanning  a  directory.  The pattern is a PCRE
                 regular  expression,  and  is  matched  against   the   final
                 component  of the file name, not the entire path. The -F, -w,
                 and -x options do not apply to this pattern. The  option  may
                 be  given  any  number  of times in order to specify multiple
                 patterns. If a file name matches both  an  --include  and  an
                 --exclude pattern, it is excluded. There is no short form for
                 this option.

       --exclude-from=filename
                 Treat each non-empty line of the file  as  the  data  for  an
                 --exclude option. What constitutes a newline when reading the
                 file is the operating system's default. The --newline  option
                 has  no  effect on this option. This option may be given more
                 than once in order to specify a number of files to read.

       --exclude-dir=pattern
                 Directories whose names match the pattern are skipped without
                 being  processed,  whatever  the  setting  of the --recursive
                 option. This applies to all directories,  whether  listed  on
                 the command line, obtained from --file-list, or by scanning a
                 parent directory. The pattern is a PCRE  regular  expression,
                 and  is  matched against the final component of the directory
                 name, not the entire path. The -F, -w, and -x options do  not
                 apply  to this pattern. The option may be given any number of
                 times in order  to  specify  more  than  one  pattern.  If  a
                 directory matches both --include-dir and --exclude-dir, it is
                 excluded. There is no short form for this option.

       -F, --fixed-strings
                 Interpret each data-matching  pattern  as  a  list  of  fixed
                 strings,  separated  by  newlines,  instead  of  as a regular
                 expression. What constitutes a newline for  this  purpose  is
                 controlled  by the --newline option. The -w (match as a word)
                 and -x (match whole line) options can be used with -F.   They
                 apply to each of the fixed strings. A line is selected if any
                 of the fixed strings are found in it (subject to -w or -x, if
                 present).  This  option applies only to the patterns that are
                 matched against the contents of files; it does not  apply  to
                 patterns  specified  by  any  of  the  --include or --exclude
                 options.

       -f filename, --file=filename
                 Read patterns from the file, one per  line,  and  match  them
                 against  each  line of input. What constitutes a newline when
                 reading the file  is  the  operating  system's  default.  The
                 --newline option has no effect on this option. 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 -e
                 above.

                 If this option is given more than  once,  all  the  specified
                 files  are read. A data line is output if any of the patterns
                 match it. A filename can be given as  "-"  to  refer  to  the
                 standard  input.  When  -f is used, patterns specified on the
                 command line using -e 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 the
                 names of paths to be searched.

       --file-list=filename
                 Read  a  list  of  files  and/or  directories  that are to be
                 scanned from the given file, one  per  line.  Trailing  white
                 space is removed from each line, and blank lines are ignored.
                 These paths are processed before any that are listed  on  the
                 command  line.  The  filename can be given as "-" to refer to
                 the standard input.   If  --file  and  --file-list  are  both
                 specified  as  "-",  patterns  are read first. This is useful
                 only when the  standard  input  is  a  terminal,  from  which
                 further  lines  (the list of files) can be read after an end-
                 of-file indication. If this option is given more  than  once,
                 all the specified files are read.

       --file-offsets
                 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 -A, -B, and -C 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  --line-
                 offsets and --only-matching.

       -H, --with-filename
                 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.

       -h, --no-filename
                 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.

       --help    Output a help message, giving brief details  of  the  command
                 options  and  file type support, and then exit. Anything else
                 on the command line is ignored.

       -I        Treat binary files as never matching. This is  equivalent  to
                 --binary-files=without-match.

       -i, --ignore-case
                 Ignore upper/lower case distinctions during comparisons.

       --include=pattern
                 If  any --include patterns are specified, the only files that
                 are processed are those that match one of the  patterns  (and
                 do  not  match  an  --exclude  pattern). This option does not
                 affect directories, but it  applies  to  all  files,  whether
                 listed  on the command line, obtained from --file-list, or by
                 scanning  a  directory.  The  pattern  is  a   PCRE   regular
                 expression, and is matched against the final component of the
                 file name, not the entire path. The -F, -w, and -x options do
                 not apply to this pattern. The option may be given any number
                 of times. If a file name matches both  an  --include  and  an
                 --exclude  pattern,  it  is excluded.  There is no short form
                 for this option.

       --include-from=filename
                 Treat each non-empty line of the file  as  the  data  for  an
                 --include option. What constitutes a newline for this purpose
                 is the operating system's default. The --newline  option  has
                 no effect on this option. This option may be given any number
                 of times; all the files are read.

       --include-dir=pattern
                 If  any  --include-dir  patterns  are  specified,  the   only
                 directories  that  are  processed are those that match one of
                 the patterns (and do not  match  an  --exclude-dir  pattern).
                 This  applies  to  all  directories,  whether  listed  on the
                 command line, obtained from --file-list,  or  by  scanning  a
                 parent  directory.  The pattern is a PCRE regular expression,
                 and is matched against the final component of  the  directory
                 name,  not the entire path. The -F, -w, and -x options do not
                 apply to this pattern. The option may be given any number  of
                 times.   If   a  directory  matches  both  --include-dir  and
                 --exclude-dir, it is excluded. There is  no  short  form  for
                 this option.

       -L, --files-without-match
                 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.

       -l, --files-with-matches
                 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  normally stops as soon as a matching line is found
                 in a file. However, if the -c (count) option  is  also  used,
                 matching  continues in order to obtain the correct count, and
                 those files that have at least one  match  are  listed  along
                 with  their  counts.  Using  this  option with -c is a way of
                 suppressing the listing of files with no matches.

       --label=name
                 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.

       --line-buffered
                 When this option is given, input is read and  processed  line
                 by  line,  and  the  output  is  flushed after each write. By
                 default, input is read in large chunks, unless  pcregrep  can
                 determine  that  it  is  reading  from  a  terminal (which is
                 currently possible only in Unix-like environments). Output to
                 terminal  is  normally automatically flushed by the operating
                 system. This option can be useful when the input or output is
                 attached  to a pipe and you do not want pcregrep to buffer up
                 large  amounts  of  data.  However,  its  use   will   affect
                 performance, and the -M (multiline) option ceases to work.

       --line-offsets
                 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 -n option), and the offset and length  are
                 separated  by  a  comma.  In  this mode, no context is shown.
                 That is, the -A, -B, and -C 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  --file-
                 offsets and --only-matching.

       --locale=locale-name
                 This  option  specifies  a  locale  to  be  used  for pattern
                 matching. It overrides the value in the  LC_ALL  or  LC_CTYPE
                 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.

       --match-limit=number
                 Processing  some  regular  expression  patterns can require a
                 very large amount of memory,  leading  in  some  cases  to  a
                 program crash if not enough is available.  Other patterns may
                 take a very long time to search  for  all  possible  matching
                 strings.  The pcre_exec() function that is called by pcregrep
                 to do the matching has two  parameters  that  can  limit  the
                 resources that it uses.

                 The   --match-limit  option  provides  a  means  of  limiting
                 resource usage when processing patterns that are not going to
                 match, but which have a very large number of possibilities in
                 their search trees. The classic example  is  a  pattern  that
                 uses  nested  unlimited  repeats.  Internally,  PCRE  uses  a
                 function called match() which it calls repeatedly  (sometimes
                 recursively).  The  limit  set by --match-limit is imposed on
                 the number of times this function is called during  a  match,
                 which  has  the effect of limiting the amount of backtracking
                 that can take place.

                 The --recursion-limit option is similar to --match-limit, but
                 instead of limiting the total number of times that match() is
                 called, it limits the depth of recursive calls, which in turn
                 limits  the  amount of memory that can be used. The recursion
                 depth is a smaller number than the  total  number  of  calls,
                 because not all calls to match() are recursive. This limit is
                 of use only if it is set smaller than --match-limit.

                 There are no short  forms  for  these  options.  The  default
                 settings  are  specified  when  the PCRE library is compiled,
                 with the default default being 10 million.

       -M, --multiline
                 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  a successful match may consist of more than
                 one line, the last of which is the one  in  which  the  match
                 ended. If the matched string ends with a newline sequence the
                 output ends at the end of that 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 pcregrep buffers
                 the input file as it scans it. However, pcregrep 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. This option  does  not  work  when
                 input is read line by line (see --line-buffered.)

       -N newline-type, --newline=newline-type
                 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  (form
                 feed,  U+000C),  NEL (next line, U+0085), LS (line separator,
                 U+2028), and PS (paragraph separator, U+2029).

                 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,  pcregrep  uses the library's default.  The
                 possible values for this option are CR, LF, CRLF, ANYCRLF, or
                 ANY.  This  makes  it  possible to use pcregrep to scan 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,
                 pcregrep  may  behave  in strange ways. Note that this option
                 does not apply to files specified by the -f,  --exclude-from,
                 or  --include-from  options,  which  are  expected to use the
                 operating system's standard newline sequence.

       -n, --line-number
                 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 --line-
                 offsets is used.

       --no-jit  If the PCRE library is built with  support  for  just-in-time
                 compiling  (which speeds up matching), pcregrep automatically
                 makes use of this, unless it was explicitly disabled at build
                 time.  This  option  can be used to disable the use of JIT at
                 run time. It  is  provided  for  testing  and  working  round
                 problems.  It should never be needed in normal use.

       -o, --only-matching
                 Show only the part of the line that matched a pattern instead
                 of the whole line. In this mode, no context  is  shown.  That
                 is,  the -A, -B, and -C options are ignored. If there is more
                 than one match in a line, each of them is  shown  separately.
                 If  -o  is combined with -v (invert the sense of the match to
                 find non-matching lines), no output  is  generated,  but  the
                 return  code  is set appropriately. If the matched portion of
                 the line is empty, nothing is output unless the file name  or
                 line  number  are being printed, in which case they are shown
                 on an otherwise empty line. This option is mutually exclusive
                 with --file-offsets and --line-offsets.

       -onumber, --only-matching=number
                 Show  only  the  part  of the line that matched the capturing
                 parentheses  of  the  given  number.  Up  to   32   capturing
                 parentheses  are  supported,  and  -o0  is  equivalent  to -o
                 without a number. Because these options can be given  without
                 an  argument  (see above), if an argument is present, it must
                 be given in the same shell item, for example, -o3 or  --only-
                 matching=2.  The  comments  given  for  the non-argument case
                 above also apply to this case.  If  the  specified  capturing
                 parentheses  do  not exist in the pattern, or were not set in
                 the match, nothing is output unless the  file  name  or  line
                 number are being printed.

                 If  this  option is given multiple times, multiple substrings
                 are output, in the order the options are given. For  example,
                 -o3  -o1  -o3  causes  the  substrings  matched  by capturing
                 parentheses 3 and 1  and  then  3  again  to  be  output.  By
                 default, there is no separator (but see the next option).

       --om-separator=text
                 Specify  a  separating string for multiple occurrences of -o.
                 The default is an empty string. Separating strings are  never
                 coloured.

       -q, --quiet
                 Work quietly, that is, display nothing except error messages.
                 The exit status indicates whether or  not  any  matches  were
                 found.

       -r, --recursive
                 If  any given path is a directory, recursively scan the files
                 it contains, taking  note  of  any  --include  and  --exclude
                 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 -d option to
                 "recurse".

       --recursion-limit=number
                 See --match-limit above.

       -s, --no-messages
                 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.

       -u, --utf-8
                 Operate in UTF-8 mode. This option is available only if  PCRE
                 has been compiled with UTF-8 support. All patterns (including
                 those for  any  --exclude  and  --include  options)  and  all
                 subject lines that are scanned must be valid strings of UTF-8
                 characters.

       -V, --version
                 Write the version numbers of pcregrep and the PCRE library to
                 the  standard  output  and  then  exit.  Anything else on the
                 command line is ignored.

       -v, --invert-match
                 Invert the sense of the match, so that  lines  which  do  not
                 match any of the patterns are the ones that are found.

       -w, --word-regex, --word-regexp
                 Force  the  patterns  to  match  only  whole  words.  This is
                 equivalent to having \b at the start and end of the  pattern.
                 This  option  applies  only  to the patterns that are matched
                 against the contents of files; it does not apply to  patterns
                 specified by any of the --include or --exclude options.

       -x, --line-regex, --line-regexp
                 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. This option applies only to the patterns that
                 are matched against the contents of files; it does not  apply
                 to  patterns  specified  by any of the --include or --exclude
                 options.

ENVIRONMENT VARIABLES


       The environment variables LC_ALL and LC_CTYPE  are  examined,  in  that
       order,  for  a  locale.  The first one that is set is used. This can be
       overridden by the --locale option.  If  no  locale  is  set,  the  PCRE
       library's default (usually the "C" locale) is used.

NEWLINES


       The  -N (--newline) option allows pcregrep to scan files with different
       newline conventions from the default. Any parts of the input files that
       are  written  to  the  standard  output  are  copied  identically, with
       whatever newline sequences they have in the input. However, the setting
       of this option does not affect the interpretation of files specified by
       the -f, --exclude-from, or --include-from options, which are assumed to
       use  the  operating  system's  standard  newline  sequence, nor does it
       affect the way in which pcregrep writes informational messages  to  the
       standard error and output streams. For these it uses the string "
" to
       indicate newlines, relying on the C I/O library to convert this  to  an
       appropriate sequence.

OPTIONS COMPATIBILITY


       Many  of the short and long forms of pcregrep's options are the same as
       in the GNU grep program. Any long option of the form --xxx-regexp  (GNU
       terminology)  is  also  available  as  --xxx-regex  (PCRE terminology).
       However,  the  --file-list,  --file-offsets,   --include-dir,   --line-
       offsets, --locale, --match-limit, -M, --multiline, -N, --newline, --om-
       separator, --recursion-limit, -u, and --utf-8 options are  specific  to
       pcregrep,  as is the use of the --only-matching option with a capturing
       parentheses number.

       Although most of the common options  work  the  same  way,  a  few  are
       different  in pcregrep. For example, the --include option's argument is
       a glob for GNU grep, but a regular expression for pcregrep. If both the
       -c  and  -l  options are given, GNU grep lists only file names, without
       counts, but pcregrep gives the counts.

OPTIONS WITH DATA


       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 (with one exception) in the next command line item. For
       example:

         -f/some/file
         -f /some/file

       The  exception is the -o option, which may appear with or without data.
       Because of this, if data is present, it must follow immediately in  the
       same item, for example -o3.

       If  a long form option is used, the data may appear in the same command
       line item, separated by an equals character, or (with  two  exceptions)
       it may appear in the next command line item. For example:

         --file=/some/file
         --file /some/file

       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.

       The exceptions to the above are the --colour (or --color)  and  --only-
       matching  options,  for  which  the  data  is optional. If one of these
       options does have data, it must be given in the first  form,  using  an
       equals character. Otherwise pcregrep will assume that it has no data.

MATCHING ERRORS


       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, pcregrep outputs an error message and the line that caused the
       problem  to  the  standard error stream. If there are more than 20 such
       errors, pcregrep gives up.

       The --match-limit option of pcregrep can be used  to  set  the  overall
       resource  limit; there is a second option called --recursion-limit that
       sets a limit on the amount of memory (usually stack) that is used  (see
       the discussion of these options above).

DIAGNOSTICS


       Exit status is 0 if any matches were found, 1 if no matches were found,
       and 2 for syntax errors, overlong lines, non-existent  or  inaccessible
       files  (even if matches were found in other files) or too many matching
       errors.  Using  the  -s  option  to  suppress  error   messages   about
       inaccessible files does not affect the return code.

SEE ALSO


       pcrepattern(3), pcresyntax(3), pcretest(1).

AUTHOR


       Philip Hazel
       University Computing Service
       Cambridge CB2 3QH, England.

REVISION


       Last updated: 03 April 2014
       Copyright (c) 1997-2014 University of Cambridge.



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