Command: gnu grep
GREP searches the named input files (or standard input if no files are
named, or the file name - is given) for lines containing a match to the
given pattern. By default, grep prints the matching lines.
grep [-[[AB] ]<num>] [-[CEFGVchilnqsvwx]] [-[ef]] <expr> [<files...>]
All variants of grep understand the following options:
-num Matches will be printed with num lines of leading and
trailing context. However, grep will never print any given
line more than once.
-A num Print num lines of trailing context after matching lines.
-B num Print num lines of leading context before matching lines.
-C Equivalent to -2.
-V Print the version number of grep to standard error. This
version number should be included in all bug reports
-b Print the byte offset within the input file before
each line of output.
-c Suppress normal output; instead print a count of matching
lines for each input file. With the -v option (see below),
count non-matching lines.
-e pattern Use pattern as the pattern; useful to protect patterns
beginning with -.
-f file Obtain the pattern from file.
-h Suppress the prefixing of filenames on output when
multiple files are searched.
-i Ignore case distinctions in both the pattern and the
-L Suppress normal output; instead print the name of each
input file from which no output would normally have been
-l Suppress normal output; instead print the name of each in-
put file from which output would normally have been printed.
-n Prefix each line of output with the line number within
its input file.
-q Quiet; suppress normal output.
-s Suppress error messages about nonexistent or unreadable
-v Invert the sense of matching, to select non-matching lines.
-w Select only those lines containing matches that form whole
words. The test is that the matching substring must either
be at the beginning of the line, or preceded by a non-word
constituent character. Similarly, it must be either at the
end of the line or followed by a non-word constituent
character. Word-constituent characters are letters, digits,
and the underscore.
-x Select only those matches that exactly match the whole line.
There are three major variants of grep, controlled by the following
-G Interpret pattern as a basic regular expression
(see below). This is the default.
-E Interpret pattern as an extended regular expression
-F Interpret pattern as a list of fixed strings, sepa-
rated by newlines, any of which is to be matched.
In addition, two variant programs egrep and fgrep are
available. Egrep is similiar (but not identical) to
grep -E, and is compatible with the historical Unix egrep.
Fgrep is the same as grep -F.
GREP has an extensive documentation that is beyond the scope of
this help. For more information see:
Copyright © 1995 Stephen McConnel, help version 2023 W. Spiegl.
This file is derived from the FreeDOS Spec Command HOWTO.
See the file H2Cpying for copying conditions.