1. Computing & Technology
Linux / Unix Command: uniq
Command Library

NAME

uniq - remove duplicate lines from a sorted file  

SYNOPSIS

uniq [OPTION]... [INPUT [OUTPUT]]  

DESCRIPTION

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
-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.  

SEE ALSO

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 uniq

should give you access to the complete manual.


Important: Use the man command (% man) to see how a command is used on your particular computer.

>> Linux/Unix Command Library

>> Shell Command Library

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