By way of contrast, here's what a threaded solution might look like:

#! perl -slw
use strict;
use threads;
use Thread::Queue;
use Win32::Console;

my $con = new Win32::Console STD_OUTPUT_HANDLE;
$con->Cls( $FG_LIGHTBLUE | $BG_WHITE );

my $Qcon = new Thread::Queue;

async{
    while( my( $what, $where ) = split $;, $Qcon->dequeue ) {
        $con->WriteChar( $what, 5, $where );
    }
}->detach;

sub writer {
    my $pos = shift;
    my $counter = 0;
    while( 1 ) {
        $Qcon->enqueue( join $;, ++$counter, $pos );
        select '','','', rand( 0.2 );
    }
}

my @writers = map threads->create( \&writer, $_ ), 5, 15;

sleep 100;
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It is windows only, but adapting it to *nix shouldn't be too hard.

The real benefit shows up when you start to want to do something useful in the threads.