HP-UX Reference (11i v2 07/12) - 1 User Commands A-M (vol 1)

c
comm(1) comm(1)
NAME
comm - select or reject lines common to two sorted files
SYNOPSIS
comm [-[123]] file1 file2
DESCRIPTION
comm reads file1 and file2, which should be ordered in increasing collating sequence (see sort(1) and
Environment Variables below), and produces a three-column output:
Column 1: Lines that appear only in file1,
Column 2: Lines that appear only in file2,
Column 3: Lines that appear in both files.
If
- is used for file1 or file2, the standard input is used.
Options 1, 2, or 3 suppress printing of the corresponding column. Thus
comm -12
prints only the lines
common to the two files;
comm -23
prints only lines in the first file but not in the second; comm -123
does nothing useful.
EXTERNAL INFLUENCES
Environment Variables
LC_COLLATE determines the collating sequence comm expects from the input files.
LC_MESSAGES determines the language in which messages are displayed.
If LC_MESSAGES is not specified in the environment or is set to the empty string, the value of
LANG
determines the language in which messages are displayed. If LC_COLLATE is not specified in the
environment or is set to the empty string, the value of LANG is used as a default. If
LANG is not specified
or is set to the empty string, a default of ‘‘C’’ (see lang(5)) is used instead of
LANG. If any internationaliza-
tion variable contains an invalid setting,
comm behaves as if all internationalization variables are set to
‘‘C’’. See environ(5).
International Code Set Support
Single- and multi-byte character code sets are supported.
EXAMPLES
The following examples assume that file1 and file2 have been ordered in the collating sequence
defined by the LC_COLLATE or LANG environment variable.
Print all lines common to file1 and file2 (in other words, print column 3):
comm -12 file1 file2
Print all lines that appear in file1 but not in file2 (in other words, print column 1):
comm -23 file1 file2
Print all lines that appear in file2 but not in file1 (in other words, print column 2):
comm -13 file1 file2
SEE ALSO
cmp(1), diff(1), sdiff(1), sort(1), uniq(1).
STANDARDS CONFORMANCE
comm: SVID2, SVID3, XPG2, XPG3, XPG4, POSIX.2
HP-UX 11i Version 2: December 2007 Update − 1 − Hewlett-Packard Company 169