If the file is sorted you might want to checkout the Search::Dict module. I found it to be amazing fast. I used it in my search engine 192283 Basically it works like 
    my $newpos=look *FILE, $string, 0, 0;

Q: Why did the Perlmonk cross the road?
A: He wanted to escape the match.

In reply to Re: fast lookups in files by Vennis
in thread fast lookups in files by citromatik

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