NAME

uniq − report repeated lines in a file

SYNOPSIS

uniq [ options ] [ input [ output ] ]

DESCRIPTION

Uniq reads the input file comparing adjacent lines.  In the normal case, the second and succeeding copies of repeated lines are removed; the remainder is written on the output file.  Note that repeated lines must be adjacent in order to be found; see sort(1). 

OPTIONS

The n arguments specify skipping an initial portion of each line in the comparison:

−n The first n fields together with any blanks before each are ignored.  A field is defined as a string of non-space, non-tab characters separated by tabs and spaces from its neighbors. 

+n The first n characters are ignored.  Fields are skipped before characters. 

Other options include:

−c Supersedes −u and −d.  Generates an output report in default style but with each line preceded by a count of the number of times it occurred. 

−d Prints one copy of the repeated lines only. 

−u Outputs only the lines that are not repeated in the original file.  (By default, uniq outputs one occurrence of the repeated lines.) 

The normal mode output is the union of the −u and −d mode outputs. 

SEE ALSO

sort(1), comm(1)

INTEGRATED SOLUTIONS 4.3 BSD  —  April 29, 1985