How long will it need to run before you are convinced that the OP is safe to use this?
Did I ever claim otherwise?

All I've been claiming is that if you're seeding a deterministic random number generator with k bits, you will not be getting more than 2k sequences, and that I've seen no evidence whatsoever that you can pull more out of thin air.

After generating 254 sets of 1 million 25-char keys, with each key being generated at a new seed position, NO DUPS SEEN!
254 sets of 1 million keys? Call me confused, but: 
for my $run  ( 1 .. 1e6 ) {
    ...
    for my $id ( 1 .. 1e6 ) {
        srand ( $run + $id );
        ...
    }
}

[download]
Aren't you generating a million sets of a million keys each? But with only 2 million different keys, as $run + $id ranges from 2 .. 2e6.

But never mind that. I've never questioned that picking a different seed is very likely to give you a different key. My claim is, that if you have only 232 different seeds you will not get more than 232 keys this way. You exercise showed that if you pick a million different seeds, you get a million different keys. And you repeated that experiment a million times, each time removing a single seed from the set of a million, and adding another one.

In reply to Re^15: How likely is rand() to repeat? by JavaFan
in thread How likely is rand() to repeat? by desertrat

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