Why do you feel that you can't keep track of which host was previously called? Have you seen Storable and DBM::Deep?

Another solution, which can be just as problematic as using rand may be to use Time::HiRes. Divide a second into 4 quarters and choose which host to use based on which quarter you are in at runtime.

Thanks ya'll, I forgot to mention that my hosts needed to be in a list...also the reason I wanted to not require an external call is because the script calling my hosts doesn't belong to me thus I was attempting to make the code simple and not require additional Modules to be installed/called...

After some thought/research I have decided upon the following code as my solution...



#!/usr/bin/perl

sub get_hosts {
   @hosts=("host1.domain.com","host1.domain.com","host1.domain.com","h
+ost1.domain.com"); 
   @app = ();
   while (@hosts) {
       $rv = int(rand(@hosts));
        push @app,$hosts[$rv];
        $hosts[$rv] = $hosts[$#hosts];
        pop @hosts;
    }
    $thosts = "$app[0],$app[1],$app[2],$app[3]";
    return $thosts;
}

print &get_hosts();
[download]

Thanks again everyone for your suggestions...

Danny

#!/usr/bin/perl
use warnings;
use strict;

my @server_list = ( 'server1', 'server2', 'server3', 'server4' ); 
my @picked = ( 0,0,0,0 );

my $picks = shift;
foreach ( 1 .. $picks ) {
    my $i = int(rand( scalar @server_list ));
    print "Guess = $i\n";
    while ( $picked[$i] ) {
        $i = int(rand ( scalar @server_list ));
        print "Guess = $i\n";
    };
    for my $j ( 0 .. $#server_list ) {
        if ( $j == $i )  {
            $picked[$j] = 1;
        }
        else  {
            $picked[$j] = 0;
        }
     }
     print "Chosen => ", $i, "\n";
}
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C:\Code>perl no_repeats.pl 5
Guess = 1
Chosen => 1
Guess = 3
Chosen => 3
Guess = 1
Chosen => 1
Guess = 1
Guess = 1
Guess = 0
Chosen => 0
Guess = 0
Guess = 0
Guess = 3
Chosen => 3
[download]

EXCELLENT THOUGHT dwm042...I can see what you mean...I will definitely use this concept in the future...

Thanks,
Danny

Here's a simple way to pick a random string:

use strict;

my @hosts = (
  "host1",
  "host2",
  "host3",
  "host4",
);

my $pick = $hosts[rand @hosts];
print "host: $pick\n";
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An easy way to implement what you might need is to use round robin load balancing via DNS. Look Ma, No Code Whatsoever!

You could get better answers if you specified some background on why you need the requirements that you stated because different load balancing schemes are better for various goals.

sub RnR
{
        push my @list, @_;
        return sub
        {
                my $r = 1 + int rand(@list-1);

                # swap [0] with [$r]
                my $t = $list[$r];
                $list[$r] = $list[0];
                $list[0] = $t;

                return $t;
        }
}

# usage
my $rnr = RnR(qw(a b c d e f g));
print "next :", $rnr->(), "\n" for (1..20);
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Oha

Remember that you ensure the task in question takes so long to process that it actually justifies to being sent over the network (and back again) + the overhead and complexity it represents.