linux man page for comm

COMM(1) 							   User Commands							   COMM(1)

NAME
       comm - compare two sorted files line by line

SYNOPSIS
       comm [OPTION]... FILE1 FILE2

DESCRIPTION
       Compare sorted files FILE1 and FILE2 line by line.

       With  no  options,  produce three-column output.  Column one contains lines unique to FILE1, column two contains lines unique to FILE2, and
       column three contains lines common to both files.

       -1     suppress column 1 (lines unique to FILE1)

       -2     suppress column 2 (lines unique to FILE2)

       -3     suppress column 3 (lines that appear in both files)

       --check-order
	      check that the input is correctly sorted, even if all input lines are pairable

       --nocheck-order
	      do not check that the input is correctly sorted

       --output-delimiter=STR
	      separate columns with STR

       --help display this help and exit

       --version
	      output version information and exit

       Note, comparisons honor the rules specified by `LC_COLLATE'.

EXAMPLES
       comm -12 file1 file2
	      Print only lines present in both file1 and file2.

       comm -3
	      file1 file2  Print lines in file1 not in file2, and vice versa.

AUTHOR
       Written by Richard M. Stallman and David MacKenzie.

REPORTING BUGS
       Report comm bugs to bug-coreutils@gnu.org
       GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
       General help using GNU software: <http://www.gnu.org/gethelp/>
       Report comm translation bugs to <http://translationproject.org/team/>

COPYRIGHT
       Copyright (C) 2010 Free Software Foundation, Inc.  License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
       This is free software: you are free to change and redistribute it.  There is NO WARRANTY, to the extent permitted by law.

SEE ALSO
       join(1), uniq(1)

       The full documentation for comm is maintained as a Texinfo manual.  If the info and comm programs are properly installed at your site,  the
       command

	      info coreutils 'comm invocation'

       should give you access to the complete manual.

GNU coreutils 8.5						   February 2011							   COMM(1)