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Linux 2.6 - man page for grep (linux section 1)

GREP(1) 										  GREP(1)

NAME
       grep, egrep, fgrep, rgrep - print lines matching a pattern

SYNOPSIS
       grep [OPTIONS] PATTERN [FILE...]
       grep [OPTIONS] [-e PATTERN | -f FILE] [FILE...]

DESCRIPTION
       grep  searches  the  named  input  FILEs (or standard input if no files are named, or if a
       single hyphen-minus (-) is given as file name) for lines containing a match to  the  given
       PATTERN.  By default, grep prints the matching lines.

       In  addition,  three  variant programs egrep, fgrep and rgrep are available.  egrep is the
       same as grep -E.  fgrep is the same as grep -F.	rgrep is the  same  as	grep -r.   Direct
       invocation  as  either  egrep  or fgrep is deprecated, but is provided to allow historical
       applications that rely on them to run unmodified.

OPTIONS
   Generic Program Information
       --help Print a usage message briefly summarizing these command-line options and	the  bug-
	      reporting address, then exit.

       -V, --version
	      Print  the  version  number  of  grep  to the standard output stream.  This version
	      number should be included in all bug reports (see below).

   Matcher Selection
       -E, --extended-regexp
	      Interpret PATTERN as an extended regular	expression  (ERE,  see	below).   (-E  is
	      specified by POSIX.)

       -F, --fixed-strings
	      Interpret  PATTERN  as a list of fixed strings, separated by newlines, any of which
	      is to be matched.  (-F is specified by POSIX.)

       -G, --basic-regexp
	      Interpret PATTERN as a basic regular expression (BRE,  see  below).   This  is  the
	      default.

       -P, --perl-regexp
	      Interpret  PATTERN  as a Perl regular expression (PCRE, see below).  This is highly
	      experimental and grep -P may warn of unimplemented features.

   Matching Control
       -e PATTERN, --regexp=PATTERN
	      Use PATTERN as the pattern.  This can be used to specify multiple search	patterns,
	      or to protect a pattern beginning with a hyphen (-).  (-e is specified by POSIX.)

       -f FILE, --file=FILE
	      Obtain  patterns	from  FILE, one per line.  The empty file contains zero patterns,
	      and therefore matches nothing.  (-f is specified by POSIX.)

       -i, --ignore-case
	      Ignore case distinctions in both the PATTERN and the input files.  (-i is specified
	      by POSIX.)

       -v, --invert-match
	      Invert  the  sense  of matching, to select non-matching lines.  (-v is specified by
	      POSIX.)

       -w, --word-regexp
	      Select only those lines containing matches that form whole words.  The test is that
	      the  matching substring must either be at the beginning of the line, or preceded by
	      a non-word constituent character.  Similarly, it must be either at the end  of  the
	      line  or followed by a non-word constituent character.  Word-constituent characters
	      are letters, digits, and the underscore.

       -x, --line-regexp
	      Select only those matches that exactly match the whole line.  (-x is  specified  by
	      POSIX.)

       -y     Obsolete synonym for -i.

   General Output Control
       -c, --count
	      Suppress	normal	output;  instead  print  a count of matching lines for each input
	      file.  With the -v, --invert-match option (see below),  count  non-matching  lines.
	      (-c is specified by POSIX.)

       --color[=WHEN], --colour[=WHEN]
	      Surround	the  matched  (non-empty)  strings,  matching  lines, context lines, file
	      names, line numbers, byte offsets, and separators (for fields and groups of context
	      lines)  with escape sequences to display them in color on the terminal.  The colors
	      are defined by the environment variable GREP_COLORS.   The  deprecated  environment
	      variable	GREP_COLOR  is	still  supported, but its setting does not have priority.
	      WHEN is never, always, or auto.

       -L, --files-without-match
	      Suppress normal output; instead print the name of each input  file  from	which  no
	      output  would  normally  have  been  printed.   The scanning will stop on the first
	      match.

       -l, --files-with-matches
	      Suppress normal output; instead print the name of each input file from which output
	      would  normally have been printed.  The scanning will stop on the first match.  (-l
	      is specified by POSIX.)

       -m NUM, --max-count=NUM
	      Stop reading a file after NUM matching lines.  If the input is standard input  from
	      a  regular  file, and NUM matching lines are output, grep ensures that the standard
	      input is positioned to just after the last matching line before exiting, regardless
	      of  the  presence  of  trailing  context	lines.	This enables a calling process to
	      resume a search.	When grep stops after NUM matching lines, it outputs any trailing
	      context  lines.  When the -c or --count option is also used, grep does not output a
	      count greater than NUM.  When the -v or --invert-match option is	also  used,  grep
	      stops after outputting NUM non-matching lines.

       -o, --only-matching
	      Print only the matched (non-empty) parts of a matching line, with each such part on
	      a separate output line.

       -q, --quiet, --silent
	      Quiet; do not write anything to standard output.	Exit immediately with zero status
	      if  any  match  is  found,  even	if  an	error  was  detected.  Also see the -s or
	      --no-messages option.  (-q is specified by POSIX.)

       -s, --no-messages
	      Suppress error messages about nonexistent or unreadable files.   Portability  note:
	      unlike  GNU grep, 7th Edition Unix grep did not conform to POSIX, because it lacked
	      -q and its -s option behaved like GNU grep's -q option.  USG-style grep also lacked
	      -q  but  its  -s option behaved like GNU grep.  Portable shell scripts should avoid
	      both -q and -s and should redirect standard and error output to /dev/null  instead.
	      (-s is specified by POSIX.)

   Output Line Prefix Control
       -b, --byte-offset
	      Print the 0-based byte offset within the input file before each line of output.  If
	      -o (--only-matching) is specified, print the offset of the matching part itself.

       -H, --with-filename
	      Print the file name for each match.  This is the default when there  is  more  than
	      one file to search.

       -h, --no-filename
	      Suppress	the prefixing of file names on output.	This is the default when there is
	      only one file (or only standard input) to search.

       --label=LABEL
	      Display input actually coming from standard input as input coming from file  LABEL.
	      This is especially useful when implementing tools like zgrep, e.g., gzip -cd foo.gz
	      | grep --label=foo -H something.	See also the -H option.

       -n, --line-number
	      Prefix each line of output with the 1-based line number within its input file.  (-n
	      is specified by POSIX.)

       -T, --initial-tab
	      Make  sure  that	the first character of actual line content lies on a tab stop, so
	      that the alignment of tabs looks normal.	This is useful with options  that  prefix
	      their  output  to  the  actual  content:	-H,-n,	and  -b.  In order to improve the
	      probability that lines from a single file will all start at the same  column,  this
	      also causes the line number and byte offset (if present) to be printed in a minimum
	      size field width.

       -u, --unix-byte-offsets
	      Report Unix-style byte offsets.  This switch causes grep to report byte offsets  as
	      if  the  file  were  a Unix-style text file, i.e., with CR characters stripped off.
	      This will produce results identical to running grep on a Unix machine.  This option
	      has  no  effect  unless -b option is also used; it has no effect on platforms other
	      than MS-DOS and MS-Windows.

       -Z, --null
	      Output a zero byte (the ASCII NUL character) instead of the character that normally
	      follows  a  file	name.	For example, grep -lZ outputs a zero byte after each file
	      name instead of the usual newline.  This option makes the output unambiguous,  even
	      in  the  presence  of file names containing unusual characters like newlines.  This
	      option can be used with commands like find -print0, perl -0, sort -z, and xargs  -0
	      to process arbitrary file names, even those that contain newline characters.

   Context Line Control
       -A NUM, --after-context=NUM
	      Print NUM lines of trailing context after matching lines.  Places a line containing
	      a group separator (--) between contiguous  groups  of  matches.	With  the  -o  or
	      --only-matching option, this has no effect and a warning is given.

       -B NUM, --before-context=NUM
	      Print NUM lines of leading context before matching lines.  Places a line containing
	      a group separator (--) between contiguous  groups  of  matches.	With  the  -o  or
	      --only-matching option, this has no effect and a warning is given.

       -C NUM, -NUM, --context=NUM
	      Print NUM lines of output context.  Places a line containing a group separator (--)
	      between contiguous groups of matches.  With the -o or --only-matching option,  this
	      has no effect and a warning is given.

   File and Directory Selection
       -a, --text
	      Process	a   binary   file  as  if  it  were  text;  this  is  equivalent  to  the
	      --binary-files=text option.

       --binary-files=TYPE
	      If the first few bytes of a file indicate  that  the  file  contains  binary  data,
	      assume  that  the  file  is  of  type  TYPE.   By default, TYPE is binary, and grep
	      normally outputs either a one-line message saying that a binary file matches, or no
	      message if there is no match.  If TYPE is without-match, grep assumes that a binary
	      file does not match; this is equivalent to the -I option.  If TYPE  is  text,  grep
	      processes  a  binary  file as if it were text; this is equivalent to the -a option.
	      Warning: grep --binary-files=text might output binary garbage, which can have nasty
	      side effects if the output is a terminal and if the terminal driver interprets some
	      of it as commands.

       -D ACTION, --devices=ACTION
	      If an input file is a device, FIFO  or  socket,  use  ACTION  to	process  it.   By
	      default,	ACTION	is  read,  which means that devices are read just as if they were
	      ordinary files.  If ACTION is skip, devices are silently skipped.

       -d ACTION, --directories=ACTION
	      If an input file is a directory, use ACTION to process it.  By default,  ACTION  is
	      read,  which  means  that directories are read just as if they were ordinary files.
	      If ACTION is skip, directories are silently skipped.  If ACTION  is  recurse,  grep
	      reads  all  files  under	each directory, recursively; this is equivalent to the -r
	      option.

       --exclude=GLOB
	      Skip files whose base name matches GLOB (using  wildcard	matching).   A	file-name
	      glob  can use *, ?, and [...]  as wildcards, and \ to quote a wildcard or backslash
	      character literally.

       --exclude-from=FILE
	      Skip files whose base name matches any of the file-name globs read from FILE (using
	      wildcard matching as described under --exclude).

       --exclude-dir=DIR
	      Exclude directories matching the pattern DIR from recursive searches.

       -I     Process a binary file as if it did not contain matching data; this is equivalent to
	      the --binary-files=without-match option.

       --include=GLOB
	      Search only files  whose	base  name  matches  GLOB  (using  wildcard  matching  as
	      described under --exclude).

       -R, -r, --recursive
	      Read  all  files	under  each  directory, recursively; this is equivalent to the -d
	      recurse option.

   Other Options
       --line-buffered
	      Use line buffering on output.  This can cause a performance penalty.

       --mmap If possible, use the mmap(2) system call to read	input,	instead  of  the  default
	      read(2)  system  call.   In  some  situations,  --mmap  yields  better performance.
	      However, --mmap can cause undefined behavior (including core  dumps)  if	an  input
	      file shrinks while grep is operating, or if an I/O error occurs.

       -U, --binary
	      Treat the file(s) as binary.  By default, under MS-DOS and MS-Windows, grep guesses
	      the file type by looking at the contents of the first 32KB read from the file.   If
	      grep decides the file is a text file, it strips the CR characters from the original
	      file  contents  (to  make  regular  expressions  with  ^	and  $	work  correctly).
	      Specifying  -U overrules this guesswork, causing all files to be read and passed to
	      the matching mechanism verbatim; if the file is a text file with CR/LF pairs at the
	      end  of  each  line, this will cause some regular expressions to fail.  This option
	      has no effect on platforms other than MS-DOS and MS-Windows.

       -z, --null-data
	      Treat the input as a set of lines, each terminated by a zero byte  (the  ASCII  NUL
	      character)  instead of a newline.  Like the -Z or --null option, this option can be
	      used with commands like sort -z to process arbitrary file names.

REGULAR EXPRESSIONS
       A regular expression is a pattern that describes a set of  strings.   Regular  expressions
       are  constructed  analogously  to  arithmetic  expressions,  by using various operators to
       combine smaller expressions.

       grep understands three different versions of regular  expression  syntax:  "basic"  (BRE),
       "extended"  (ERE)  and  "perl"  (PRCE).	In  GNU grep, there is no difference in available
       functionality between basic  and  extended  syntaxes.   In  other  implementations,  basic
       regular	expressions  are  less	powerful.   The following description applies to extended
       regular expressions; differences for basic regular expressions are summarized  afterwards.
       Perl   regular	expressions   give   additional  functionality,  and  are  documented  in
       pcresyntax(3) and pcrepattern(3), but may not be available on every system.

       The fundamental building blocks are the regular expressions that match a single character.
       Most  characters,  including  all  letters  and digits, are regular expressions that match
       themselves.  Any meta-character with special meaning may be quoted by preceding it with	a
       backslash.

       The period . matches any single character.

   Character Classes and Bracket Expressions
       A  bracket  expression is a list of characters enclosed by [ and ].  It matches any single
       character in that list; if the first character of the list is the caret ^ then it  matches
       any  character  not in the list.  For example, the regular expression [0123456789] matches
       any single digit.

       Within a bracket expression, a range expression consists of two characters separated by	a
       hyphen.	It matches any single character that sorts between the two characters, inclusive,
       using the locale's collating sequence and character set.  For example, in  the  default	C
       locale,	[a-d] is equivalent to [abcd].	Many locales sort characters in dictionary order,
       and in these locales [a-d] is typically not equivalent to [abcd]; it might  be  equivalent
       to   [aBbCcDd],	for  example.	To  obtain  the  traditional  interpretation  of  bracket
       expressions, you can use the C locale by setting the LC_ALL environment	variable  to  the
       value C.

       Finally, certain named classes of characters are predefined within bracket expressions, as
       follows.  Their names are self explanatory, and they are [:alnum:], [:alpha:],  [:cntrl:],
       [:digit:],   [:graph:],	 [:lower:],   [:print:],  [:punct:],  [:space:],  [:upper:],  and
       [:xdigit:].  For example, [[:alnum:]] means [0-9A-Za-z], except the  latter  form  depends
       upon  the  C locale and the ASCII character encoding, whereas the former is independent of
       locale and character set.  (Note that the brackets in these class names are  part  of  the
       symbolic  names,  and  must be included in addition to the brackets delimiting the bracket
       expression.)  Most meta-characters lose their special meaning inside bracket  expressions.
       To  include  a  literal	]  place it first in the list.	Similarly, to include a literal ^
       place it anywhere but first.  Finally, to include a literal - place it last.

   Anchoring
       The caret ^ and the dollar sign $ are meta-characters that respectively	match  the  empty
       string at the beginning and end of a line.

   The Backslash Character and Special Expressions
       The  symbols  \<  and \> respectively match the empty string at the beginning and end of a
       word.  The symbol \b matches the empty string at the edge of a word, and  \B  matches  the
       empty  string  provided	it's  not  at the edge of a word.  The symbol \w is a synonym for
       [[:alnum:]] and \W is a synonym for [^[:alnum:]].

   Repetition
       A regular expression may be followed by one of several repetition operators:
       ?      The preceding item is optional and matched at most once.
       *      The preceding item will be matched zero or more times.
       +      The preceding item will be matched one or more times.
       {n}    The preceding item is matched exactly n times.
       {n,}   The preceding item is matched n or more times.
       {n,m}  The preceding item is matched at least n times, but not more than m times.

   Concatenation
       Two regular expressions may be concatenated; the resulting regular expression matches  any
       string  formed  by  concatenating  two substrings that respectively match the concatenated
       expressions.

   Alternation
       Two regular expressions may be joined by the  infix  operator  |;  the  resulting  regular
       expression matches any string matching either alternate expression.

   Precedence
       Repetition  takes  precedence  over  concatenation,  which  in  turn takes precedence over
       alternation.  A whole  expression  may  be  enclosed  in  parentheses  to  override  these
       precedence rules and form a subexpression.

   Back References and Subexpressions
       The back-reference \n, where n is a single digit, matches the substring previously matched
       by the nth parenthesized subexpression of the regular expression.

   Basic vs Extended Regular Expressions
       In basic regular expressions the meta-characters ?, +, {, |, (, and ) lose  their  special
       meaning; instead use the backslashed versions \?, \+, \{, \|, \(, and \).

       Traditional  egrep  did	not  support the { meta-character, and some egrep implementations
       support \{ instead, so portable scripts should avoid { in grep -E patterns and should  use
       [{] to match a literal {.

       GNU  grep -E attempts to support traditional usage by assuming that { is not special if it
       would be the start of  an  invalid  interval  specification.   For  example,  the  command
       grep -E '{1'  searches for the two-character string {1 instead of reporting a syntax error
       in the regular expression.  POSIX.2 allows this behavior as  an	extension,  but  portable
       scripts should avoid it.

ENVIRONMENT VARIABLES
       The behavior of grep is affected by the following environment variables.

       The  locale  for category LC_foo is specified by examining the three environment variables
       LC_ALL, LC_foo, LANG, in that order.  The first of these variables that is  set	specifies
       the  locale.  For example, if LC_ALL is not set, but LC_MESSAGES is set to pt_BR, then the
       Brazilian Portuguese locale is used for the LC_MESSAGES category.  The C locale is used if
       none of these environment variables are set, if the locale catalog is not installed, or if
       grep was not compiled with national language support (NLS).

       GREP_OPTIONS
	      This variable specifies default options to be  placed  in  front	of  any  explicit
	      options.	  For	example,   if	GREP_OPTIONS   is   '--binary-files=without-match
	      --directories=skip', grep behaves as if  the  two  options  --binary-files=without-
	      match  and  --directories=skip  had  been  specified  before  any explicit options.
	      Option specifications are separated by whitespace.  A backslash  escapes	the  next
	      character,  so  it  can  be  used  to  specify an option containing whitespace or a
	      backslash.

       GREP_COLOR
	      This variable specifies the color used to highlight matched (non-empty)  text.   It
	      is  deprecated  in  favor  of GREP_COLORS, but still supported.  The mt, ms, and mc
	      capabilities of GREP_COLORS have priority over it.  It can only specify  the  color
	      used to highlight the matching non-empty text in any matching line (a selected line
	      when the -v  command-line  option  is  omitted,  or  a  context  line  when  -v  is
	      specified).   The  default  is 01;31, which means a bold red foreground text on the
	      terminal's default background.

       GREP_COLORS
	      Specifies the colors and other attributes used to highlight various  parts  of  the
	      output.	Its  value  is	a  colon-separated  list of capabilities that defaults to
	      ms=01;31:mc=01;31:sl=:cx=:fn=35:ln=32:bn=32:se=36  with  the  rv	and  ne   boolean
	      capabilities omitted (i.e., false).  Supported capabilities are as follows.

	      sl=    SGR  substring  for  whole  selected lines (i.e., matching lines when the -v
		     command-line option is omitted, or non-matching lines when -v is specified).
		     If however the boolean rv capability and the -v command-line option are both
		     specified, it applies to context matching lines  instead.	 The  default  is
		     empty (i.e., the terminal's default color pair).

	      cx=    SGR  substring for whole context lines (i.e., non-matching lines when the -v
		     command-line option is omitted, or matching lines when -v is specified).  If
		     however  the  boolean  rv capability and the -v command-line option are both
		     specified, it applies to selected non-matching lines instead.   The  default
		     is empty (i.e., the terminal's default color pair).

	      rv     Boolean  value  that  reverses  (swaps)  the  meanings  of  the  sl= and cx=
		     capabilities when the -v command-line option is specified.  The  default  is
		     false (i.e., the capability is omitted).

	      mt=01;31
		     SGR  substring  for  matching  non-empty  text in any matching line (i.e., a
		     selected line when the -v command-line option is omitted, or a context  line
		     when  -v  is specified).  Setting this is equivalent to setting both ms= and
		     mc= at once to the same value.  The default is a bold  red  text  foreground
		     over the current line background.

	      ms=01;31
		     SGR substring for matching non-empty text in a selected line.  (This is only
		     used when the -v command-line option is omitted.)	The effect of the sl= (or
		     cx=  if  rv) capability remains active when this kicks in.  The default is a
		     bold red text foreground over the current line background.

	      mc=01;31
		     SGR substring for matching non-empty text in a context line.  (This is  only
		     used  when  the -v command-line option is specified.)  The effect of the cx=
		     (or sl= if rv) capability remains active when this kicks in.  The default is
		     a bold red text foreground over the current line background.

	      fn=35  SGR  substring  for file names prefixing any content line.  The default is a
		     magenta text foreground over the terminal's default background.

	      ln=32  SGR substring for line numbers prefixing any content line.  The default is a
		     green text foreground over the terminal's default background.

	      bn=32  SGR substring for byte offsets prefixing any content line.  The default is a
		     green text foreground over the terminal's default background.

	      se=36  SGR substring for separators that are inserted between selected line  fields
		     (:),  between context line fields, (-), and between groups of adjacent lines
		     when nonzero context  is  specified  (--).   The  default	is  a  cyan  text
		     foreground over the terminal's default background.

	      ne     Boolean  value that prevents clearing to the end of line using Erase in Line
		     (EL) to Right (\33[K) each time a colorized item ends.  This  is  needed  on
		     terminals on which EL is not supported.  It is otherwise useful on terminals
		     for which the back_color_erase (bce) boolean terminfo  capability	does  not
		     apply,  when  the	chosen	highlight colors do not affect the background, or
		     when EL is too slow or causes too much flicker.  The default is false (i.e.,
		     the capability is omitted).

	      Note  that boolean capabilities have no =...  part.  They are omitted (i.e., false)
	      by default and become true when specified.

	      See the Select Graphic Rendition (SGR) section in the  documentation  of	the  text
	      terminal	that  is  used	for  permitted	values	and  their  meaning  as character
	      attributes.  These substring values are integers in decimal representation and  can
	      be  concatenated	with semicolons.  grep takes care of assembling the result into a
	      complete SGR sequence (\33[...m).  Common values to concatenate include 1 for bold,
	      4 for underline, 5 for blink, 7 for inverse, 39 for default foreground color, 30 to
	      37 for foreground colors, 90 to 97 for 16-color mode foreground colors,  38;5;0  to
	      38;5;255	for  88-color  and  256-color  modes  foreground  colors,  49 for default
	      background color, 40 to 47 for background colors, 100  to  107  for  16-color  mode
	      background  colors,  and	48;5;0	to  48;5;255  for  88-color  and  256-color modes
	      background colors.

       LC_ALL, LC_COLLATE, LANG
	      These variables specify the locale for the LC_COLLATE  category,	which  determines
	      the collating sequence used to interpret range expressions like [a-z].

       LC_ALL, LC_CTYPE, LANG
	      These  variables specify the locale for the LC_CTYPE category, which determines the
	      type of characters, e.g., which characters are whitespace.

       LC_ALL, LC_MESSAGES, LANG
	      These variables specify the locale for the LC_MESSAGES category,	which  determines
	      the  language  that  grep  uses  for  messages.  The default C locale uses American
	      English messages.

       POSIXLY_CORRECT
	      If set, grep behaves as POSIX.2 requires; otherwise, grep behaves more  like  other
	      GNU programs.  POSIX.2 requires that options that follow file names must be treated
	      as file names; by default, such options are permuted to the front  of  the  operand
	      list  and are treated as options.  Also, POSIX.2 requires that unrecognized options
	      be diagnosed as "illegal", but since they  are  not  really  against  the  law  the
	      default	is   to  diagnose  them  as  "invalid".   POSIXLY_CORRECT  also  disables
	      _N_GNU_nonoption_argv_flags_, described below.

       _N_GNU_nonoption_argv_flags_
	      (Here N is grep's numeric process ID.)  If the ith character  of	this  environment
	      variable's  value  is  1,  do not consider the ith operand of grep to be an option,
	      even if it appears to be one.  A shell can put this variable in the environment for
	      each  command  it  runs,	specifying  which  operands  are the results of file name
	      wildcard expansion and therefore should not be treated as options.   This  behavior
	      is available only with the GNU C library, and only when POSIXLY_CORRECT is not set.

EXIT STATUS
       The  exit  status  is  0  if  selected  lines  are found, and 1 if not found.  If an error
       occurred the exit status is 2.  (Note: POSIX error handling code should check for  '2'  or
       greater.)

COPYRIGHT
       Copyright 1998-2000, 2002, 2005-2011 Free Software Foundation, Inc.

       This  is  free software; see the source for copying conditions.	There is NO warranty; not
       even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

BUGS
   Reporting Bugs
       Email  bug  reports  to	<bug-grep@gnu.org>,  a	 mailing   list   whose   web	page   is
       <http://lists.gnu.org/mailman/listinfo/bug-grep>.   grep's Savannah bug tracker is located
       at <http://savannah.gnu.org/bugs/?group=grep>.

   Known Bugs
       Large repetition counts in the {n,m} construct may cause grep to use lots of  memory.   In
       addition,  certain  other  obscure regular expressions require exponential time and space,
       and may cause grep to run out of memory.

       Back-references are very slow, and may require exponential time.

SEE ALSO
   Regular Manual Pages
       awk(1), cmp(1), diff(1), find(1), gzip(1), perl(1), sed(1), sort(1),  xargs(1),	zgrep(1),
       mmap(2), read(2), pcre(3), pcresyntax(3), pcrepattern(3), terminfo(5), glob(7), regex(7).

   POSIX Programmer's Manual Page
       grep(1p).

   TeXinfo Documentation
       The  full  documentation for grep is maintained as a TeXinfo manual.  If the info and grep
       programs are properly installed at your site, the command

	      info grep

       should give you access to the complete manual.

NOTES
       GNU's not Unix, but Unix is a beast; its plural form is Unixen.

User Commands				   GNU grep 2.9 				  GREP(1)


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