- Produce three tab-separated columns: lines only in first file, lines only in second file and common lines:comm [file1] [file2]- Print only lines common to both files:comm -12 [file1] [file2]- Print only lines common to both files, reading one file from stdin:cat [file1] | comm -12 - [file2]- Get lines only found in first file, saving the result to a third file:comm -23 [file1] [file2] > [file1_only]- Print lines only found in second file, when the files aren't sorted:comm -13 <(sort [file1]) <(sort [file2])
comm [,OPTION/]... ,FILE1 FILE2/
Compare sorted files FILE1 and FILE2 line by line.
When FILE1 or FILE2 (not both) is -, read standard input.
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.
Note, comparisons honor the rules specified by 'LC_COLLATE'.
Written by Richard M. Stallman and David MacKenzie.
GNU coreutils online help: <http://www.gnu.org/software/coreutils/> Report comm translation bugs to <http://translationproject.org/team/>
Copyright © 2016 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.
Full documentation at: <http://www.gnu.org/software/coreutils/comm> or available locally via: info '(coreutils) comm invocation'