1.\" $OpenBSD: comm.1,v 1.7 2000/03/05 00:28:52 aaron Exp $ 2.\" $NetBSD: comm.1,v 1.4 1995/03/26 09:25:50 glass Exp $ 3.\" 4.\" Copyright (c) 1989, 1990, 1993 5.\" The Regents of the University of California. All rights reserved. 6.\" 7.\" This code is derived from software contributed to Berkeley by 8.\" the Institute of Electrical and Electronics Engineers, Inc. 9.\" 10.\" Redistribution and use in source and binary forms, with or without 11.\" modification, are permitted provided that the following conditions 12.\" are met: 13.\" 1. Redistributions of source code must retain the above copyright 14.\" notice, this list of conditions and the following disclaimer. 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in the 17.\" documentation and/or other materials provided with the distribution. 18.\" 3. All advertising materials mentioning features or use of this software 19.\" must display the following acknowledgement: 20.\" This product includes software developed by the University of 21.\" California, Berkeley and its contributors. 22.\" 4. Neither the name of the University nor the names of its contributors 23.\" may be used to endorse or promote products derived from this software 24.\" without specific prior written permission. 25.\" 26.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36.\" SUCH DAMAGE. 37.\" 38.\" @(#)comm.1 8.1 (Berkeley) 6/6/93 39.\" 40.Dd June 6, 1993 41.Dt COMM 1 42.Os 43.Sh NAME 44.Nm comm 45.Nd select or reject lines common to two files 46.Sh SYNOPSIS 47.Nm comm 48.Op Fl 123f 49.Ar file1 file2 50.Sh DESCRIPTION 51The 52.Nm 53utility reads 54.Ar file1 55and 56.Ar file2 , 57which should be 58sorted lexically, and produces three text 59columns as output: lines only in 60.Ar file1 ; 61lines only in 62.Ar file2 ; 63and lines in both files. 64.Pp 65The filename 66.Dq - 67means the standard input. 68.Pp 69The options are as follows: 70.Bl -tag -width Ds 71.It Fl 1 72Suppress printing of column 1. 73.It Fl 2 74Suppress printing of column 2. 75.It Fl 3 76Suppress printing of column 3. 77.It Fl f 78Fold case in line comparisons. 79.El 80.Pp 81Each column will have a number of tab characters prepended to it 82equal to the number of lower numbered columns that are being printed. 83For example, if column number two is being suppressed, lines printed 84in column number one will not have any tabs preceding them, and lines 85printed in column number three will have one. 86.Pp 87.Nm 88assumes that the files are lexically sorted; all characters 89participate in line comparisons. 90.\" .Sh ENVIRONMENT 91.\" .Bl -tag -width indent 92.\" .It Ev LANG 93.\" .It Ev LC_ALL 94.\" .It Ev LC_CTYPE 95.\" .It Ev LC_COLLATE 96.\" .It Ev LC_MESSAGES 97.\" .El 98.Pp 99The 100.Nm 101utility exits 0 on success or >0 if an error occurred. 102.Sh SEE ALSO 103.Xr cmp 1 , 104.Xr diff 1 , 105.Xr sort 1 , 106.Xr uniq 1 107.Sh STANDARDS 108The 109.Nm 110utility conforms to 111.St -p1003.2-92 . 112