UNIQ(1)                       User Commands                       UNIQ(1)

NAME
       uniq - report or omit repeated lines

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

DESCRIPTION
       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  occur‐
       rence.

       Mandatory  arguments  to  long  options  are  mandatory  for short
       options too.

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

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

       -D     print all duplicate lines

       --all-repeated[=METHOD]
              like -D, but allow separating groups with  an  empty  line;
              METHOD={none(default),prepend,separate}

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

       --group[=METHOD]
              show  all  items,  separating  groups  with  an empty line;
              METHOD={separate(default),prepend,append,both}

       -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

       --version
              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 adja‐
       cent.  You may want to sort the input  first,  or  use  'sort  -u'
       without 'uniq'.

AUTHOR
       Written by Richard M. Stallman and David MacKenzie.

REPORTING BUGS
       GNU  coreutils  online  help:  <https://www.gnu.org/software/core‐
       utils/>
       Report   any   translation   bugs   to    <https://translationpro‐
       ject.org/team/>

COPYRIGHT
       Copyright  ©  2020 Free Software Foundation, Inc.  License GPLv3+:
       GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
       This is free software: you are free to change and redistribute it.
       There is NO WARRANTY, to the extent permitted by law.

SEE ALSO
       comm(1), join(1), sort(1)

       Full documentation <https://www.gnu.org/software/coreutils/uniq>
       or available locally via: info '(coreutils) uniq invocation'

GNU coreutils 8.32              April 2020                        UNIQ(1)