Name

uniq — report or omit repeated lines

Synopsis

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

DESCRIPTION

Discard all but one of successive identical lines from INPUT (or standard input), writing to OUTPUT (or standard output).

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

−D, −−all−repeated[=delimit−method]

print all duplicate lines delimit−method={none(default),prepend,separate} Delimiting is done with blank lines.

−f, −−skip−fields=N

avoid comparing the first N fields

−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

end lines with 0 byte, 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 whitespace, then non−whitespace characters. Fields are skipped before chars.

[Note] 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'.

AUTHOR

Written by Richard Stallman and David MacKenzie.

REPORTING BUGS

Report bugs to <bug−coreutils@gnu.org>.

SEE ALSO

The full documentation for uniq is maintained as a Texinfo manual. If the info and uniq programs are properly installed at your site, the command

info uniq

should give you access to the complete manual.

COPYRIGHT

Copyright © 2008 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://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.