NAME¶

SYNOPSIS¶

DESCRIPTION¶

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

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 adjacent. You may want to sort the input first, or use 'sort -u' without 'uniq'. Also, comparisons honor the rules specified by 'LC_COLLATE'.

AUTHOR¶

REPORTING BUGS¶

COPYRIGHT¶

SEE ALSO¶

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