To see if it's file IO that's slowing you down, compare the runtime of this snippet with your original: 
while (<IN_FILE>)
{
    print OUTFILE $_;
}

[download]
If there's no significant difference, then you're optimizing in the wrong place :(

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re: Search and Replace. by QM
in thread Search and Replace. by Doniv

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