NAME

       grep, g - search a file for a pattern

SYNOPSIS

       grep [ option ...  ] pattern [ file ...  ]

       g [ option ...  ] pattern [ file ...  ]

DESCRIPTION

       Grep  searches  the  input  files  (standard  input  default) for lines that match the pattern, a regular
       expression as defined in regexp(7) with the addition of a newline character as an alternative (substitute
       for |) with lowest precedence.  Normally, each line matching the pattern is `selected', and each selected
       line is copied to the standard output.  The options are

       -c     Print only a count of matching lines.
       -h     Do not print file name tags (headers) with output lines.
       -e     The following argument is taken as a pattern.  This option makes it easy to specify patterns  that
              might confuse argument parsing, such as -n.
       -i     Ignore  alphabetic case distinctions.  The implementation folds into lower case all letters in the
              pattern and input before interpretation.  Matched lines are printed in their original form.
       -l     (ell) Print the names of files with selected lines; don't print the lines.
       -L     Print the names of files with no selected lines; the converse of -l.
       -n     Mark each printed line with its line number counted in its file.
       -s     Produce no output, but return status.
       -v     Reverse: print lines that do not match the pattern.
       -f     The pattern argument is the name of a file containing regular expressions one per line.
       -b     Don't buffer the output: write each output line as soon as it is discovered.

       Output lines are tagged by file name when there is more than one input file.   (To  force  this  tagging,
       include /dev/null as a file name argument.)

       Care  should  be taken when using the shell metacharacters $*[^|()=\ and newline in pattern; it is safest
       to enclose the entire expression in single quotes '...'.  An expression starting with '*' will treat  the
       rest of the expression as literal characters.

       G  invokes  grep  with  -n  and  forces tagging of output lines by file name.  If no files are listed, it
       searches all files matching

              *.C *.b *.c *.h *.m *.cc *.java *.cgi *.pl *.py *.tex *.ms

SOURCE

       /src/cmd/grep
       /bin/g

SEE ALSO

       ed(1), awk(1), sed(1), sam(1), regexp(7)

DIAGNOSTICS

       Exit status is null if any lines are selected, or non-null when no lines are selected or an error occurs.

                                                                                                    GREP(1plan9)