Comm (1) Linux Manual Page

comm – compare two sorted files line by line

Synopsis

comm [,OPTION/]… ,FILE1 FILE2/

Description

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.

-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
–total: output a summary
-z, –zero-terminated: line delimiter is NUL, not newline
–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: <https://www.gnu.org/software/coreutils/>
Report any translation bugs to <https://translationproject.org/team/>

Copyright

Copyright © 2020 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://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.

comm (1) Linux Manual Page