UNIQ(1) BSD Reference Manual UNIQ(1)NAMEuniq - report or filter out repeated lines in a file
SYNOPSISuniq [-c | -d | -u] [-i] [-f fields] [-s chars]
[input_file [output_file]]
DESCRIPTION
The uniq utility reads the standard input comparing adjacent lines and
writes a copy of each unique input line to the standard output. The
second and succeeding copies of identical adjacent input lines are not
written. Repeated lines in the input will not be detected if they are not
adjacent, so it may be necessary to sort the files first.
The options are as follows:
-c Precede each output line with the count of the number of times
the line occurred in the input, followed by a single space.
-d Only output lines which have duplicates.
-f fields
Ignore the first fields in each input line when doing comparis-
ons. A field is a string of non-blank characters separated from
adjacent fields by blanks. Field numbers are one based, i.e., the
first field is field one.
-i Compare case-insensitively.
-s chars
Ignore the first chars characters in each input line when doing
comparisons. If specified in conjunction with the -f option, the
first chars characters after the first fields fields will be ig-
nored. Character numbers are one based, i.e., the first character
is character one.
-u Only output lines which are unique.
If additional arguments are specified on the command line, the first such
argument is used as the name of an input file, the second is used as the
name of an output file. A file name of '-' denotes the standard input or
the standard output (depending on its position on the command line).
The uniq utility exits 0 on success or >0 if an error occurred.
SEE ALSOsort(1)STANDARDS
The historic +number and -number options have been deprecated but are
still supported in this implementation.
The uniq utility is expected to be IEEE Std 1003.2 ("POSIX.2") compati-
ble.
The -i option has been added in MirOS #8.
MirOS BSD #10-current December 8, 2002 1
