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
prefix lines by the number of occurrences
only print duplicate lines, one for each group
print all duplicate lines groups can be delimited with an empty
avoid comparing the first N fields
show all items, separating groups with an empty line
ignore differences in case when comparing
avoid comparing the first N characters
only print unique lines
end lines with 0 byte, not newline
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.
There is NO WARRANTY, to the extent permitted by law.
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
info coreutils 'uniq invocation'
should give you access to the complete manual.
GNU coreutils 8.22 February 2016 UNIQ(1)