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. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" From: @(#)uniq.1 8.1 (Berkeley) 6/6/93 32.\" $FreeBSD$ 33.\" 34.Dd May 1, 2018 35.Dt UNIQ 1 36.Os 37.Sh NAME 38.Nm uniq 39.Nd report or filter out repeated lines in a file 40.Sh SYNOPSIS 41.Nm 42.Op Fl c 43.Op Fl d | Fl u 44.Op Fl i 45.Op Fl f Ar num 46.Op Fl s Ar chars 47.Oo 48.Ar input_file 49.Op Ar output_file 50.Oc 51.Sh DESCRIPTION 52The 53.Nm 54utility reads the specified 55.Ar input_file 56comparing adjacent lines, and writes a copy of each unique input line to 57the 58.Ar output_file . 59If 60.Ar input_file 61is a single dash 62.Pq Sq Fl 63or absent, the standard input is read. 64If 65.Ar output_file 66is absent, standard output is used for output. 67The second and succeeding copies of identical adjacent input lines are 68not written. 69Repeated lines in the input will not be detected if they are not adjacent, 70so it may be necessary to sort the files first. 71.Pp 72The following options are available: 73.Bl -tag -width Ds 74.It Fl c , Fl -count 75Precede each output line with the count of the number of times the line 76occurred in the input, followed by a single space. 77.It Fl d , Fl -repeated 78Only output lines that are repeated in the input. 79.It Fl f Ar num , Fl -skip-fields Ar num 80Ignore the first 81.Ar num 82fields in each input line when doing comparisons. 83A field is a string of non-blank characters separated from adjacent fields 84by blanks. 85Field numbers are one based, i.e., the first field is field one. 86.It Fl i , Fl -ignore-case 87Case insensitive comparison of lines. 88.It Fl s Ar chars , Fl -skip-chars Ar chars 89Ignore the first 90.Ar chars 91characters in each input line when doing comparisons. 92If specified in conjunction with the 93.Fl f , Fl -unique 94option, the first 95.Ar chars 96characters after the first 97.Ar num 98fields will be ignored. 99Character numbers are one based, i.e., the first character is character one. 100.It Fl u , Fl -unique 101Only output lines that are not repeated in the input. 102.\".It Fl Ns Ar n 103.\"(Deprecated; replaced by 104.\".Fl f ) . 105.\"Ignore the first n 106.\"fields on each input line when doing comparisons, 107.\"where n is a number. 108.\"A field is a string of non-blank 109.\"characters separated from adjacent fields 110.\"by blanks. 111.\".It Cm \&\(pl Ns Ar n 112.\"(Deprecated; replaced by 113.\".Fl s ) . 114.\"Ignore the first 115.\".Ar m 116.\"characters when doing comparisons, where 117.\".Ar m 118.\"is a 119.\"number. 120.El 121.Sh ENVIRONMENT 122The 123.Ev LANG , 124.Ev LC_ALL , 125.Ev LC_COLLATE 126and 127.Ev LC_CTYPE 128environment variables affect the execution of 129.Nm 130as described in 131.Xr environ 7 . 132.Sh EXIT STATUS 133.Ex -std 134.Sh COMPATIBILITY 135The historic 136.Cm \&\(pl Ns Ar number 137and 138.Fl Ns Ar number 139options have been deprecated but are still supported in this implementation. 140.Sh SEE ALSO 141.Xr sort 1 142.Sh STANDARDS 143The 144.Nm 145utility conforms to 146.St -p1003.1-2001 147as amended by Cor.\& 1-2002. 148.Sh HISTORY 149A 150.Nm 151command appeared in 152.At v3 . 153