ref: 6966e8d72ae8fb72ebf98909acbd464aff84a3cc
dir: /man/1/grep/
.TH GREP 1 .SH NAME grep \- pattern matching .SH SYNOPSIS .B grep [ .B -lnviLs ] .I pattern [ .IR file ... ] .SH DESCRIPTION .B Grep prints lines from each .I file that match the .IR pattern , a regular expression as defined in .IR regex (2). If no files are given, standard input is used. If more than one file is given, each line of output is preceded by the name of the file it was found in. The options are: .TP 10 .B -l Print only the name of each file that contains a match. .TP .B -L Print the name of each file that does not contain a match. .TP .B -n Precede each line of output with its line number. .TP .B -v Print only lines that do not match .IR pattern . .TP .B -i Pattern matching is case insensitive (roman letters only). .TP .B -s Do not print anything; yield only the exit status. .SH SOURCE .B /appl/cmd/grep.b .SH SEE ALSO .IR regex (2) .SH DIAGNOSTICS .I Grep returns a non-nil exit status if no matches have been made, or if an error has occurred.