Examples of using the uniq command

To remove consecutive duplicate lines from a file:

   uniq acc_nos accounts

This removes all consecutive duplicate lines from the file acc_nos and places the output in the file accounts.

To list the consecutive duplicate lines and the number of times that each occurs:

   uniq -c tel_nos errors

This lists each of the consecutive duplicate lines in the file tel_nos and the number of times that each is repeated. The results are placed in the file errors.