## 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

GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
Report comm translation bugs to <http://translationproject.org/team/>

## COPYRIGHT

Copyright © 2014 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)

Full documentation at: <http://www.gnu.org/software/coreutils/comm>
or available locally via: info (aq(coreutils) comm invocation(aq