.Dd 2015-10-08 .Dt UNIQ 1 .Os sbase .Sh NAME .Nm uniq .Nd report or filter out repeated lines in a file .Sh SYNOPSIS .Nm .Op Fl c .Op Fl d | u .Op Fl f Ar num .Op Fl s Ar num .Op Ar input Op Ar output .Sh DESCRIPTION .Nm reads the .Ar input file and writes one copy of a line from each group of consecutive duplicate lines to the .Ar output file. If no .Ar input file is given .Nm reads from stdin. If no .Ar output file is given .Nm writes to stdout. .Sh OPTIONS .Bl -tag -width Ds .It Fl c Prefix each line with the number of consecutive occurrences in .Ar input . .It Fl d | Fl u Print duplicate | unique lines only. .It Fl f Ar num | Fl s Ar num Ignore the first .Ar num fields | characters in each input line when doing comparisons. .El .Sh STANDARDS The .Nm utility is compliant with the .St -p1003.1-2013 specification.