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 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, --all-repeated[=METHOD]
print all duplicate lines groups can be delimited with an empty line METHOD={none(default),prepend,sep‐
arate}
-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
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 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'.
GNU coreutils online help: <http://www.gnu.org/software/coreutils/> Report uniq translation bugs to
comm(1), join(1), sort(1)
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 coreutils 'uniq invocation'
should give you access to the complete manual.
GNU coreutils 8.22 November 2016 UNIQ(1)
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