Rigging the shuffle to be identical on a given host is easy -- simply feed a fixed seed to srand before your first call to rand.

This makes variation between hosts easy by simply choosing a host-specific property as your seed -- perhaps a mangled hardware address? 

#!/usr/bin/perl -w
use strict;
use 5.10.0;

my ($eth) = `ifconfig` =~ /HWaddr (\S+)/;
$eth =~ s/\W//g;
{
    no warnings 'portable';
    srand hex $eth;
}

say rand for 1 .. 10;

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#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: How do I make a random shuffle deterministic? by kennethk
in thread How do I make a random shuffle deterministic? by Anonymous Monk

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