.\"
.\" Derived from comm(1), Unix 32V:
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.TH COMM 1 "3/16/03" "Heirloom Toolchest" "User Commands"
.SH NAME
comm \- select or reject lines common to two sorted files
.SH SYNOPSIS
\fBcomm\fR [\fB\-123\fR] \fIfile1 file2\fR
.SH DESCRIPTION
.I Comm
reads
.I file1
and
.I file2,
which should be ordered in the current collating sequence,
and produces a three column output: lines only in
.I file1;
lines only in
.I file2;
and lines in both files.
The filename `\-' means the standard input.
.PP
Flags 1, 2, or 3 suppress printing of the corresponding
column.
Thus
.B comm
.B \-12
prints only the lines common to the two files;
.B comm
.B \-23
prints only lines in the first file but not in the second;
.B comm
.B \-123
is a no-op.
.SH "ENVIRONMENT VARIABLES"
.TP
.BR LANG ", " LC_ALL
See
.IR locale (7).
.TP
.B LC_COLLATE
Sets the collation sequence.
.TP
.B LC_CTYPE
Determines the mapping of bytes to characters.
.SH "SEE ALSO"
cmp(1),
diff(1),
uniq(1),
locale(7)