NAME [Toc] [Back]
comm - select or reject lines common to two sorted files
SYNOPSIS [Toc] [Back]
comm [-] file1 file2
DESCRIPTION [Toc] [Back]
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 [Toc] [Back]
LC_COLLATE determines the collating sequence comm expects from the
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
internationalization variable contains an invalid setting, comm
behaves as if all internationalization variables are set to ``C''.
International Code Set Support [Toc] [Back]
Single- and multi-byte character code sets are supported.
EXAMPLES [Toc] [Back]
The following examples assume that file1 and file2 have been ordered
in the collating sequence defined by the LC_COLLATE or LANG
Print all lines common to file1 and file2 (in other words, print
Hewlett-Packard Company - 1 - HP-UX 11i Version 2: August 2003
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 [Toc] [Back]
cmp(1), diff(1), sdiff(1), sort(1), uniq(1).
STANDARDS CONFORMANCE [Toc] [Back]
comm: SVID2, SVID3, XPG2, XPG3, XPG4, POSIX.2
Hewlett-Packard Company - 2 - HP-UX 11i Version 2: August 2003 [ Back ]