sbase/uniq.1

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2012-05-21 23:46:22 +00:00
.TH UNIQ 1 sbase\-VERSION
.SH NAME
uniq \- multi-column
.SH SYNOPSIS
.B uniq
.RB [ \-cdu ]
.RI [ file ]
.SH DESCRIPTION
.B uniq
reads file and writes one copy of a line
from each group of consecutive duplicate lines
to stdout.
If no file is given, uniq reads from stdin.
.SH OPTIONS
.TP
.B \-c
prefixes each line with a count
of its consecutive occurrences in the input.
.TP
.B \-d
suppresses non-duplicate lines
(thus 'uniq -d' prints only duplicates).
.TP
.B \-u
suppresses non-unique lines
(thus 'uniq -u' prints only uniques).
.SH BUGS
The original sbase implementation of
.B uniq
supported multiple input-file arguments,
as e.g. cat and grep do.
Unfortunately, POSIX uniq treats its second argument (if present)
as an output filename and clobbers it.
Since users and scripts which rely on uniq
supporting multiple input-file arguments
would be at risk of data loss
if they ever ran into a POSIX-compatible uniq,
support for multiple input-file arguments
was removed from this implementation.