.TH UNIQ 1L "GNU Text Utilities" "FSF" \" -*- nroff -*-
.SH NAME
uniq \- remove duplicate lines from a sorted file
.SH SYNOPSIS
.B uniq
[\-cdu] [\-f skip-fields] [\-s skip-chars] [\-w check-chars]
[\-#skip-fields] [+#skip-chars] [\-\-count] [\-\-repeated] [\-\-unique]
[\-\-skip-fields=skip-fields] [\-\-skip-chars=skip-chars]
[\-\-check-chars=check-chars] [\-\-help] [\-\-version] [infile] [outfile]
.SH DESCRIPTION
This manual page
documents the GNU version of
.BR uniq .
.B uniq
prints the unique lines in a sorted file, discarding all but one of a
run of matching lines.  It can optionally show only lines that appear
exactly once, or lines that appear more than once.
.B uniq
requires sorted input because it compares only consecutive lines.
.PP
If the output file is not specified,
.B uniq
writes to the standard output.  If the input file is not specified, it
reads from the standard input.
.SS OPTIONS
.TP
.I "\-u, \-\-unique"
Only print unique lines.
.TP
.I "\-d, \-\-repeated"
Only print duplicate lines.
.TP
.I "\-c, \-\-count"
Print the number of times each line occurred along with the line.
.TP
.I "\-number, \-f, \-\-skip-fields=number"
In this option, \fInumber\fP is an integer representing the number of
fields to skip over before checking for uniqueness.  The first
\fInumber\fP fields, along with any blanks found before \fInumber\fP
fields is reached, are skipped over and not counted.  Fields are
defined as a strings of non-space, non-tab characters, that are
separated from each other by spaces and tabs.
.TP
.I "+number, \-s, \-\-skip-chars=number"
In this option, \fInumber\fP is an integer representing the number of
characters to skip over before checking for uniqueness.  The first
\fInumber\fP characters, along with any blanks found before
\fInumber\fP characters is reached, are skipped over and not counted.
If you use both the field and character skipping options, fields are
skipped over first.
.TP
.I "\-w, \-\-check-chars=number"
Specify the number of characters to compare in the lines, after
skipping any specified fields and characters.  Normally the entire
rest of the lines are compared.
.TP
.I "\-\-help"
Print a usage message and exit with a non-zero status.
.TP
.I "\-\-version"
Print version information on standard error then exit.