print lines matching a pattern

-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.)

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.

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

-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.)

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.