Same count as broquaint: 
    perl -ne 'print if!$h{$_}++' file1 file2 ... > newfile

[download]
Shorter (16): 
    perl -pe '$_=$,if$,{$_}++' file1 file2 ... > newfile

[download]

--
John.

In reply to Re: (Golf) unique by jmcnamara
in thread (Golf) unique by spurperl

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