manpagez: man(ual) pages & more
man uniq(1)
Home | html | info | man
uniq(1)                          User Commands                         uniq(1)


       uniq - report or omit repeated lines


       uniq [OPTION]... [INPUT [OUTPUT]]


       Filter  adjacent matching lines from INPUT (or standard input), writing
       to OUTPUT (or standard output).

       With no options, matching lines are merged to the first occurrence.

       Mandatory arguments to long options are  mandatory  for  short  options

       -c, --count
              prefix lines by the number of occurrences

       -d, --repeated
              only print duplicate lines, one for each group

       -D     print all duplicate lines

              like  -D,  but  allow  separating  groups  with  an  empty line;

       -f, --skip-fields=N
              avoid comparing the first N fields

              show  all  items,  separating  groups  with   an   empty   line;

       -i, --ignore-case
              ignore differences in case when comparing

       -s, --skip-chars=N
              avoid comparing the first N characters

       -u, --unique
              only print unique lines

       -z, --zero-terminated
              line delimiter is NUL, not newline

       -w, --check-chars=N
              compare no more than N characters in lines

       --help display this help and exit

              output version information and exit

       A field is a run of blanks (usually spaces and/or TABs), then non-blank
       characters.  Fields are skipped before chars.

       Note: 'uniq' does not detect repeated lines unless they  are  adjacent.
       You  may want to sort the input first, or use 'sort -u' without 'uniq'.
       Also, comparisons honor the rules specified by 'LC_COLLATE'.


       Written by Richard M. Stallman and David MacKenzie.


       GNU coreutils online help: <>
       Report uniq translation bugs to <>


       Copyright (C) 2016 Free Software Foundation, Inc.  License GPLv3+:  GNU
       GPL version 3 or later <>.
       This  is  free  software:  you  are free to change and redistribute it.
       There is NO WARRANTY, to the extent permitted by law.


       comm(1), join(1), sort(1)

       Full documentation at: <>
       or available locally via: info '(coreutils) uniq invocation'

GNU coreutils 8.25               January 2016                          uniq(1)

coreutils 8.25 - Generated Sun Jan 31 16:47:46 CST 2016
© 2000-2016
Individual documents may contain additional copyright information.