plan9 man page for grep

GREP(1) 						      General Commands Manual							   GREP(1)

NAME
       grep - search a file for a pattern

SYNOPSIS
       grep [ option ...  ] pattern [ file ...	]

DESCRIPTION
       Grep  searches  the input files (standard input default) for lines (with newlines excluded) that match the pattern, a regular expression as
       defined in regexp(6).  Normally, each line matching the pattern is `selected', and each selected line is copied	to  the  standard  output.
       The options are

       -c     Print only a count of matching lines.
       -h     Do not print file name tags (headers) with output lines.
       -i     Ignore alphabetic case distinctions.  The implementation folds into lower case all letters in the pattern and input before interpre-
	      tation.  Matched lines are printed in their original form.
       -l     (ell) Print the names of files with selected lines; don't print the lines.
       -L     Print the names of files with no selected lines; the converse of -l.
       -n     Mark each printed line with its line number counted in its file.
       -s     Produce no output, but return status.
       -v     Reverse: print lines that do not match the pattern.

       Output lines are tagged by file name when there is more than one input file.  (To force this tagging, include  /dev/null  as  a	file  name
       argument.)

       Care should be taken when using the shell metacharacters $*[^|()= and newline in pattern; it is safest to enclose the entire expression in
       single quotes '...'.

SOURCE
       /sys/src/cmd/grep.c

SEE ALSO
       ed(1), awk(1), sed(1), sam(1), regexp(6)

DIAGNOSTICS
       Exit status is null if any lines are selected, or non-null when no lines are selected or an error occurs.

																	   GREP(1)