uniq — report or omit repeated lines
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 too.
−c, −−countprefix lines by the number of occurrences
−d, −−repeatedonly 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,separate}
−f, −−skip−fields=Navoid comparing the first N fields
−−group[=METHOD]show all items, separating groups with an empty line METHOD={separate(default),prepend,append,both}
−i, −−ignore−caseignore differences in case when comparing
−s, −−skip−chars=Navoid comparing the first N characters
−u, −−uniqueonly print unique lines
−z, −−zero−terminatedline delimiter is NUL, not newline
−w, −−check−chars=Ncompare no more than N characters in lines
−−helpdisplay this help and exit
−−versionoutput 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.
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Note |
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'uniq' does not detect repeated lines unless they
are adjacent. You may want to sort the input first,
or use 'sort |
GNU coreutils online help: <http://www.gnu.org/software/coreutils/> Report uniq translation bugs to <http://translationproject.org/team/>
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.
| COPYRIGHT |
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Copyright © 2014 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. |