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     UNIQ(1)                                                   UNIQ(1)

          uniq - report repeated lines in a file

          uniq [ -udc [ +n ] [ -n ] ] [ input [ output ] ]

          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). If the -u flag is used, just the
          lines that are not repeated in the original file are output.
          The -d option specifies that one copy of just the repeated
          lines is to be written.  The normal mode output is the union
          of the -u and -d mode outputs.

          The -c option supersedes -u and -d and generates an output
          report in default style but with each line preceded by a
          count of the number of times it occurred.

          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.

          sort(1), comm(1)