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
              (see below).
  -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
              input files.
  -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
              (see below).
  -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:


  - none

See also:


  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.