.TH COMM 1
.SH NAME
comm \- print lines common to two sorted files
.SH SYNOPSIS
\fBcomm\fR [\fB\-123\fR] \fIfile1 file2\fR
.br
.de FL
.TP
\\fB\\$1\\fR
\\$2
..
.de EX
.TP 20
\\fB\\$1\\fR
# \\$2
..
.SH OPTIONS
.TP 5
.B \-1
# Suppress column 1 (lines present only in \fIfile1\fP)
.TP 5
.B \-2
# Suppress column 2 (lines present only in \fIfile2\fP)
.TP 5
.B \-3
# Suppress column 3 (lines present in both files)
.SH EXAMPLES
.TP 20
.B comm file1 file2
# Print all three columns
.TP 20
.B comm \-12 file1 file2
# Print only lines common to both files
.SH DESCRIPTION
.PP
Two sorted files are read and compared.
A three column listing is produced.
Files only in 
.I file1
are in column 1;
files only in
.I file2
are in column 2;
files common to both files are in column 3.
The file name \- means \fIstdin\fR. 
.SH "SEE ALSO"
.BR cmp (1),
.BR diff (1),
.BR sort (1).