grep/fgrep [sw] <expr> <file>...

Search a file for a pattern.

Matching lines are displayed to std out, unless c or l switch used.
grep allows 'regular expressions' in the search pattern.
fgrep only allows literals in the search pattern, but is faster.

Switches -
v	all lines except those matching are listed.
c	output count of matching lines.
l	output filenames only.
i	ignore case.
w	<expr> is searched for as a word.
n	preceed line with its line number.
b	preceed line with its block number.
