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 December 17, 2009 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 | Fl d | Fl u 43.Op Fl i 44.Op Fl f Ar num 45.Op Fl s Ar chars 46.Oo 47.Ar input_file 48.Op Ar output_file 49.Oc 50.Sh DESCRIPTION 51The 52.Nm 53utility reads the specified 54.Ar input_file 55comparing adjacent lines, and writes a copy of each unique input line to 56the 57.Ar output_file . 58If 59.Ar input_file 60is a single dash 61.Pq Sq Fl 62or absent, the standard input is read. 63If 64.Ar output_file 65is absent, standard output is used for output. 66The second and succeeding copies of identical adjacent input lines are 67not written. 68Repeated lines in the input will not be detected if they are not adjacent, 69so it may be necessary to sort the files first. 70.Pp 71The following options are available: 72.Bl -tag -width Ds 73.It Fl c 74Precede each output line with the count of the number of times the line 75occurred in the input, followed by a single space. 76.It Fl d 77Only output lines that are repeated in the input. 78.It Fl f Ar num 79Ignore the first 80.Ar num 81fields in each input line when doing comparisons. 82A field is a string of non-blank characters separated from adjacent fields 83by blanks. 84Field numbers are one based, i.e., the first field is field one. 85.It Fl s Ar chars 86Ignore the first 87.Ar chars 88characters in each input line when doing comparisons. 89If specified in conjunction with the 90.Fl f 91option, the first 92.Ar chars 93characters after the first 94.Ar num 95fields will be ignored. 96Character numbers are one based, i.e., the first character is character one. 97.It Fl u 98Only output lines that are not repeated in the input. 99.It Fl i 100Case insensitive comparison of lines. 101.\".It Fl Ns Ar n 102.\"(Deprecated; replaced by 103.\".Fl f ) . 104.\"Ignore the first n 105.\"fields on each input line when doing comparisons, 106.\"where n is a number. 107.\"A field is a string of non-blank 108.\"characters separated from adjacent fields 109.\"by blanks. 110.\".It Cm \&\(pl Ns Ar n 111.\"(Deprecated; replaced by 112.\".Fl s ) . 113.\"Ignore the first 114.\".Ar m 115.\"characters when doing comparisons, where 116.\".Ar m 117.\"is a 118.\"number. 119.El 120.Sh ENVIRONMENT 121The 122.Ev LANG , 123.Ev LC_ALL , 124.Ev LC_COLLATE 125and 126.Ev LC_CTYPE 127environment variables affect the execution of 128.Nm 129as described in 130.Xr environ 7 . 131.Sh EXIT STATUS 132.Ex -std 133.Sh COMPATIBILITY 134The historic 135.Cm \&\(pl Ns Ar number 136and 137.Fl Ns Ar number 138options have been deprecated but are still supported in this implementation. 139.Sh SEE ALSO 140.Xr sort 1 141.Sh STANDARDS 142The 143.Nm 144utility conforms to 145.St -p1003.1-2001 146as amended by Cor.\& 1-2002. 147.Sh HISTORY 148A 149.Nm 150command appeared in 151.At v3 . 152