.\" Copyright (c) 1991 Regents of the University of California.
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.\" the Institute of Electrical and Electronics Engineers, Inc.
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.\" @(#)uniq.1 6.4 (Berkeley) 6/27/91
.Nd Report or filter out repeated lines in a file.
utility reads an input file or the standard input
lines, and writes one copy of each input line on the output.
The second and succeeding copies of repeated adjacent input
Repeated lines in the input are not detected if they are
not adjacent, so it is important to
The following options are available:
Precede each output line with a count of the number
of times the line occurred in the input. For example:
.Bd -literal -offset indent
duplicate_count line_number
where the duplicate count is a blank padded field of
up to four digits followed by a space.
Suppress the writing of lines that are not repeated
Ignore the first fields on each input line when
doing comparisons, where fields is a positive
A field is a string of non-blank
characters separated from adjacent fields
Ignore the first chars characters when doing
comparisons, where chars is a positive decimal
If specified in conjunction with the
option, the first chars characters after the first
fields fields will be ignored.
Suppress the writing of lines that are repeated in
fields on each input line when doing comparisons,
A field is a string of non-blank
characters separated from adjacent fields
characters when doing comparisons, where
The following operands are available:
.Bl -tag -width output_filex
A pathname of the input file.
operand is not specified, the standard input is
A pathname of the output file.
operand is not specified, the standard
is created and an error occurs or a sugnal is caught the
.\" The following environment variables affect the execution of
.\" The locale for character classification, used to
.\" determine the characters constituting a blank in
utility exits 0 on success, and >0 if an error occurs.
utility is expected to be