IMO, the best way is not to use Perl. There's an excellent utility doing exactly this, it's called uniq, which comes standard with any flavour of Unix I've encountered, and is also present in Unix toolkits for Windows. 

    uniq in_file out_file

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Abigail

In reply to Re: Removing repeated lines from file by Abigail-II
in thread Removing repeated lines from file by matth

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