Copyright (c) 2004, Sun Microsystems, Inc. All Rights Reserved.
Copyright 1989 AT&T
Portions Copyright (c) 1992, X/Open Company Limited. All Rights Reserved.
Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/.
The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html.
This notice shall appear on any product containing this material.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
comm [-123] file1 file2
The comm utility reads file1 and file2, which must be ordered in the current collating sequence, and produces three text columns as output: lines only in file1; lines only in file2; and lines in both files.
If the input files were ordered according to the collating sequence of the current locale, the lines written will be in the collating sequence of the original lines. If not, the results are unspecified.
The following options are supported:
-1
Suppresses the output column of lines unique to file1.
-2
Suppresses the output column of lines unique to file2.
-3
Suppresses the output column of lines duplicated in file1 and file2.
The following operands are supported:
file1
A path name of the first file to be compared. If file1 is -, the standard input is used.
file2
A path name of the second file to be compared. If file2 is -, the standard input is used.
See largefile(5) for the description of the behavior of comm when encountering files greater than or equal to 2 Gbyte ( 2^31 bytes).
Example 1 Printing a list of utilities specified by files
If file1, file2, and file3 each contain a sorted list of utilities, the command
example% comm -23 file1 file2 | comm -23 - file3
prints a list of utilities in file1 not specified by either of the other files. The entry:
example% comm -12 file1 file2 | comm -12 - file3
prints a list of utilities specified by all three files. And the entry:
example% comm -12 file2 file3 | comm -23 -file1
prints a list of utilities specified by both file2 and file3, but not specified in file1.
See environ(5) for descriptions of the following environment variables that affect the execution of comm: LANG, LC_ALL, LC_COLLATE, LC_CTYPE, LC_MESSAGES, and NLSPATH.
The following exit values are returned:
0
All input files were successfully output as specified.
>0
An error occurred.
See attributes(5) for descriptions of the following attributes:
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| CSI | enabled |
| Interface Stability | Standard |
cmp(1), diff(1), sort(1), uniq(1), attributes(5), environ(5), largefile(5), standards(5)