1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" the Institute of Electrical and Electronics Engineers, Inc. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. All advertising materials mentioning features or use of this software 16.\" must display the following acknowledgement: 17.\" This product includes software developed by the University of 18.\" California, Berkeley and its contributors. 19.\" 4. Neither the name of the University nor the names of its contributors 20.\" may be used to endorse or promote products derived from this software 21.\" without specific prior written permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33.\" SUCH DAMAGE. 34.\" 35.\" From: @(#)uniq.1 8.1 (Berkeley) 6/6/93 36.\" $FreeBSD: src/usr.bin/uniq/uniq.1,v 1.5.2.5 2002/07/15 08:11:33 keramida Exp $ 37.\" $DragonFly: src/usr.bin/uniq/uniq.1,v 1.2 2003/06/17 04:29:33 dillon Exp $ 38.\" 39.Dd June 6, 1993 40.Dt UNIQ 1 41.Os 42.Sh NAME 43.Nm uniq 44.Nd report or filter out repeated lines in a file 45.Sh SYNOPSIS 46.Nm 47.Op Fl c | Fl d | Fl u 48.Op Fl i 49.Op Fl f Ar num 50.Op Fl s Ar chars 51.Oo 52.Ar input_file 53.Op Ar output_file 54.Oc 55.Sh DESCRIPTION 56The 57.Nm 58utility reads the specified 59.Ar input_file 60comparing adjacent lines, and writes a copy of each unique input line to 61the 62.Ar output_file . 63If 64.Ar input_file 65is a single dash 66.Pq Sq \&- 67or absent, the standard input is read. 68If 69.Ar output_file 70is absent, standard output is used for output. 71The second and succeeding copies of identical adjacent input lines are 72not written. 73Repeated lines in the input will not be detected if they are not adjacent, 74so it may be necessary to sort the files first. 75.Pp 76The following options are available: 77.Bl -tag -width Ds 78.It Fl c 79Precede each output line with the count of the number of times the line 80occurred in the input, followed by a single space. 81.It Fl d 82Only output lines that are repeated in the input. 83.It Fl f Ar num 84Ignore the first 85.Ar num 86fields in each input line when doing comparisons. 87A field is a string of non-blank characters separated from adjacent fields 88by blanks. 89Field numbers are one based, i.e. the first field is field one. 90.It Fl s Ar chars 91Ignore the first 92.Ar chars 93characters in each input line when doing comparisons. 94If specified in conjunction with the 95.Fl f 96option, the first 97.Ar chars 98characters after the first 99.Ar num 100fields will be ignored. 101Character numbers are one based, i.e. the first character is character one. 102.It Fl u 103Only output lines that are not repeated in the input. 104.It Fl i 105Case insensitive comparison of lines. 106.\".It Fl Ns Ar n 107.\"(Deprecated; replaced by 108.\".Fl f ) . 109.\"Ignore the first n 110.\"fields on each input line when doing comparisons, 111.\"where n is a number. 112.\"A field is a string of non-blank 113.\"characters separated from adjacent fields 114.\"by blanks. 115.\".It Cm \&\(pl Ns Ar n 116.\"(Deprecated; replaced by 117.\".Fl s ) . 118.\"Ignore the first 119.\".Ar m 120.\"characters when doing comparisons, where 121.\".Ar m 122.\"is a 123.\"number. 124.El 125.Pp 126If additional arguments are specified on the command line, the first 127argument is used as the name of an input file, the second is used 128as the name of an output file. 129.Sh EXIT STATUS 130.Ex -std 131.Sh COMPATIBILITY 132The historic 133.Cm \&\(pl Ns Ar number 134and 135.Fl Ns Ar number 136options have been deprecated but are still supported in this implementation. 137.Sh SEE ALSO 138.Xr sort 1 139.Sh STANDARDS 140The 141.Nm 142utility is expected to be 143.St -p1003.2 144compatible. 145.Sh HISTORY 146A 147.Nm 148command appeared in 149.At v3 . 150