MAN.9FRONT.ORG RTFM


     UNIQ(1)                                                   UNIQ(1)

     NAME
          uniq - report repeated lines in a file

     SYNOPSIS
          uniq [ -udcs [ +-num ] ] [ file ]

     DESCRIPTION
          Uniq copies the input file, or the standard input, to the
          standard output, comparing adjacent lines.  In the normal
          case, the second and succeeding copies of repeated lines are
          removed.  Repeated lines must be adjacent in order to be
          found.

          -u   Print unique lines.

          -d   Print (one copy of) duplicated lines.

          -c   Prefix a repetition count and a tab to each output
               line.  Implies -u and -d.

          -s   Count as a duplicate if the prefix matches the previous
               unique line.

          -num The first num 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.

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

     SOURCE
          /sys/src/cmd/uniq.c

     SEE ALSO
          sort(1)

     BUGS
          Field selection and comparison should be compatible with
          sort(1).