uniq — report or omit repeated lines
uniq
[OPTION
...] [ INPUT
[OUTPUT
] ]
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.
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Note |
---|---|
'uniq' does not detect repeated lines unless they
are adjacent. You may want to sort the input first,
or use `sort |