From what I understand, AOL users get a different IP address with every request. Also, what about corporate users going through the same proxy that gives all of them the same IP address? IP addresses are like trivia: they're interesting, but don't rely on them to be useful.

my $IP = '127.0.0.1'; # or whatever

my $abs_IP = join '', map { sprintf "%03d", $_ } split /\./, $IP;
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my $IP = '127.0.0.1';

my $abs_IP = sprintf "%03d"x4, split /\./, $IP;
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Avoid map for simple stuff. The "%03d"x4 above is computed during compilation. Also, avoid loops at runtime.

You should also consider using the resutling string as a prefix of the resulting filename for security reasons. There is File::Temp for that.

UPDATE: Ignoring the fact that this might not be as useful as one might think, you should really use a database for this type of job. It's a lot safer, faster and scalable.

It depends on what you store in each file. If you store small records of just a few bytes, you could be using 2k or 4k (or more) of disk space for each file according to your fs blocksize. Take a look to DB_File for more info.

you've introduced the equivalent of a hash collision

I think he was hoping to convert his filenames to 3 digits per octet in order to avoid that exact problem. Of course, removing the dots first won't work. And I don't understand why he'd remove the dots to "change it to a proper filename". An IP would make a fine filename, I'd think.

Shrug. As others have pointed out, this isn't likely to be an effective approach to his problem anyway because a requestor's IP can change from request to request and an IP may be shared among many requestors.

-sauoq
"My two cents aren't worth a dime.";

use strict;

while (<DATA>) {
    s/(\d+|\.)/ $1 eq '.' ? '' : sprintf "%03d", $1 /eg;
    print;
}

__DATA__
127.0.0.1
256.123.12.1
256.12.31.21
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127000000001
256123012001
256012031021
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