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GREP(1)			FreeBSD	General	Commands Manual		       GREP(1)

NAME
     grep, egrep, fgrep, zgrep,	zegrep,	zfgrep -- file pattern searcher

SYNOPSIS
     grep [-abcEFGHhIiLlnoqRsUVvwxZ] [-A num] [-B num] [-C[num]] [-e pattern]
	  [-f file] [--binary-files=value] [--context[=num]] [--line-buffered]
	  [pattern] [file ...]

DESCRIPTION
     The grep utility searches any given input files, selecting	lines that
     match one or more patterns.  By default, a	pattern	matches	an input line
     if	the regular expression (RE) in the pattern matches the input line
     without its trailing newline.  An empty expression	matches	every line.
     Each input	line that matches at least one of the patterns is written to
     the standard output.  If no file arguments	are specified, the standard
     input is used.

     grep is used for simple patterns and basic	regular	expressions (BREs);
     egrep can handle extended regular expressions (EREs).  See	re_format(7)
     for more information on regular expressions.  fgrep is quicker than both
     grep and egrep, but can only handle fixed patterns	(i.e. it does not
     interpret regular expressions).  Patterns may consist of one or more
     lines, allowing any of the	pattern	lines to match a portion of the	input.

     zgrep, zegrep, and	zfgrep act like	grep, egrep, and fgrep,	respectively,
     but accept	input files compressed with the	compress(1) or gzip(1) com-
     pression utilities.

     The following options are available:

     -A	num  Print num lines of	trailing context after each match.  See	also
	     the -B and	-C options.

     -a	     Treat all files as	ASCII text.  Normally grep will	simply print
	     ``Binary file ... matches'' if files contain binary characters.
	     Use of this option	forces grep to output lines matching the spec-
	     ified pattern.

     -B	num  Print num lines of	leading	context	before each match.  See	also
	     the -A and	-C options.

     -b	     The offset	in bytes of a matched pattern is displayed in front of
	     the respective matched line.

     -C[num]
	     Print num lines of	leading	and trailing context surrounding each
	     match.  The default is 2 and is equivalent	to -A 2	-B 2.  Note:
	     no	whitespace may be given	between	the option and its argument.

     -c	     Only a count of selected lines is written to standard output.

     -E	     Interpret pattern as an extended regular expression (i.e. force
	     grep to behave as egrep).

     -e	pattern
	     Specify a pattern used during the search of the input: an input
	     line is selected if it matches any	of the specified patterns.
	     This option is most useful	when multiple -e options are used to
	     specify multiple patterns,	or when	a pattern begins with a	dash
	     (`-').

     -F	     Interpret pattern as a set	of fixed strings (i.e. force grep to
	     behave as fgrep).

     -f	file
	     Read one or more newline separated	patterns from file.  Empty
	     pattern lines match every input line.  Newlines are not consid-
	     ered part of a pattern.  If file is empty,	nothing	is matched.

     -G	     Interpret pattern as a basic regular expression (i.e. force grep
	     to	behave as traditional grep).

     -H	     Always print filename headers (i.e. filenames) with output	lines.

     -h	     Never print filename headers (i.e.	filenames) with	output lines.

     -I	     Ignore binary files.

     -i	     Perform case insensitive matching.	 By default, grep is case sen-
	     sitive.

     -L	     Only the names of files not containing selected lines are written
	     to	standard output.  Pathnames are	listed once per	file searched.
	     If	the standard input is searched,	the string ``(standard
	     input)'' is written.

     -l	     Only the names of files containing	selected lines are written to
	     standard output.  grep will only search a file until a match has
	     been found, making	searches potentially less expensive.  Path-
	     names are listed once per file searched.  If the standard input
	     is	searched, the string ``(standard input)'' is written.

     -n	     Each output line is preceded by its relative line number in the
	     file, starting at line 1.	The line number	counter	is reset for
	     each file processed.  This	option is ignored if -c, -L, -l, or -q
	     is	specified.

     -o	     Print each	match, but only	the match, not the entire line.

     -q	     Quiet mode: suppress normal output.  grep will only search	a file
	     until a match has been found, making searches potentially less
	     expensive.

     -R	     Recursively search	subdirectories listed.

     -s	     Silent mode.  Nonexistent and unreadable files are	ignored	(i.e.
	     their error messages are suppressed).

     -U	     Search binary files, but do not attempt to	print them.

     -V	     Display version information.  All other options are ignored.

     -v	     Selected lines are	those not matching any of the specified	pat-
	     terns.

     -w	     The expression is searched	for as a word (as if surrounded	by
	     `[[:<:]]' and `[[:>:]]'; see re_format(7)).

     -x	     Only input	lines selected against an entire fixed string or regu-
	     lar expression are	considered to be matching lines.

     -Z	     Force grep	to behave as zgrep.

     --binary-files=value
	     Controls searching	and printing of	binary files.  Options are
	     binary, the default: search binary	files but do not print them;
	     without-match: do not search binary files;	and text: treat	all
	     files as text.

     --context[=num]
	     Print num lines of	leading	and trailing context.  The default is
	     2.

     --line-buffered
	     Force output to be	line buffered.	By default, output is line
	     buffered when standard output is a	terminal and block buffered
	     otherwise.

EXIT STATUS
     The grep utility exits with one of	the following values:

	   0	   One or more lines were selected.
	   1	   No lines were selected.
	   >1	   An error occurred.

EXAMPLES
     To	find all occurrences of	the word `patricia' in a file:

	   $ grep 'patricia' myfile

     To	find all occurrences of	the pattern `.Pp' at the beginning of a	line:

	   $ grep '^\.Pp' myfile

     The apostrophes ensure the	entire expression is evaluated by grep instead
     of	by the user's shell.  The caret	`^' matches the	null string at the
     beginning of a line, and the `\' escapes the `.', which would otherwise
     match any character.

     To	find all lines in a file which do not contain the words	`foo' or
     `bar':

	   $ grep -v -e	'foo' -e 'bar' myfile

     A simple example of an extended regular expression:

	   $ egrep '19|20|25' calendar

     Peruses the file `calendar' looking for either 19,	20, or 25.

SEE ALSO
     ed(1), ex(1), gzip(1), sed(1), re_format(7)

STANDARDS
     The grep utility is compliant with	the IEEE Std 1003.1-2008 (``POSIX.1'')
     specification.

     The flags [-AaBbCGHhILoRUVwZ] are extensions to that specification, and
     the behaviour of the -f flag when used with an empty pattern file is left
     undefined.

     All long options are provided for compatibility with GNU versions of this
     utility.

     Historic versions of the grep utility also	supported the flags [-ruy].
     This implementation supports those	options; however, their	use is
     strongly discouraged.

HISTORY
     The grep command first appeared in	Version	6 AT&T UNIX.

FreeBSD	9.3			August 27, 2014			   FreeBSD 9.3

NAME | SYNOPSIS | DESCRIPTION | EXIT STATUS | EXAMPLES | SEE ALSO | STANDARDS | HISTORY

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