'scuse if I got this wrong--I have used a *nix system for several years--but wouldn't this work for you(on a *nix system)? 

uniq -cd sorted_cdr >duplicates
uniq -u  sorted_cdr >unique_cdr

[download]

Of course, a perl solution will be more portable if that's a req.

In reply to Re: print out duplicate records by BrowserUk
in thread print out duplicate records by Anonymous Monk

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