1.\" Copyright (c) 1991 Regents of the University of California. 2.\" 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.\" %sccs.include.redist.roff% 8.\" 9.\" @(#)uniq.1 6.5 (Berkeley) 01/09/92 10.\" 11.Dd 12.Dt UNIQ 1 13.Os 14.Sh NAME 15.Nm uniq 16.Nd report or filter out repeated lines in a file 17.Sh SYNOPSIS 18.Nm uniq 19.Op Fl c | Fl d | Fl u 20.Op Fl f Ar fields 21.Op Fl s Ar chars 22.Oo 23.Ar input_file 24.Op Ar output_file 25.Oc 26.Sh DESCRIPTION 27The 28.Nm uniq 29utility reads the standard input comparing adjacent lines, and writes 30a copy of each unique input line to the standard output. 31The second and succeeding copies of identical adjacent input lines are 32not written. 33Repeated lines in the input will not be detected if they are not adjacent, 34so it may be necessary to sort the files first. 35.Pp 36The following options are available: 37.Bl -tag -width Ds 38.It Fl c 39Precede each output line with the count of the number of times the line 40occurred in the input, followed by a single space. 41.It Fl d 42Don't output lines that are not repeated in the input. 43.It Fl f Ar fields 44Ignore the first 45.Ar fields 46in each input line when doing comparisons. 47A field is a string of non-blank characters separated from adjacent fields 48by blanks. 49Field numbers are one based, i.e. the first field is field one. 50.It Fl s Ar chars 51Ignore the first 52.Ar chars 53characters in each input line when doing comparisons. 54If specified in conjunction with the 55.Fl f 56option, the first 57.Ar chars 58characters after the first 59.Ar fields 60fields will be ignored. 61Character numbers are one based, i.e. the first character is character one. 62.It Fl u 63Don't output lines that are repeated in the input. 64.\".It Fl Ns Ar n 65.\"(Deprecated; replaced by 66.\".Fl f ) . 67.\"Ignore the first n 68.\"fields on each input line when doing comparisons, 69.\"where n is a number. 70.\"A field is a string of non-blank 71.\"characters separated from adjacent fields 72.\"by blanks. 73.\".It Cm \&\(pl Ns Ar n 74.\"(Deprecated; replaced by 75.\".Fl s ) . 76.\"Ignore the first 77.\".Ar m 78.\"characters when doing comparisons, where 79.\".Ar m 80.\"is a 81.\"number. 82.El 83.Pp 84If additional arguments are specified on the command line, the first 85such argument is used as the name of an input file, the second is used 86as the name of an output file. 87.Pp 88The 89.Nm uniq 90utility exits 0 on success, and >0 if an error occurs. 91.Sh COMPATIBILITY 92The historic 93.Cm \&\(pl Ns Ar number 94and 95.Fl Ns Ar number 96options have been deprecated but are still supported in this implementation. 97.Sh SEE ALSO 98.Xr sort 1 99.Sh STANDARDS 100The 101.Nm uniq 102utility is expected to be 103.St -p1003.2 104compatible. 105