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

##</code><code>##

my @kids = (
    sub { print "First!",  $/; },
    sub { print "Second!", $/; },
    sub { print "Third!",  $/; },
);

pipe my ($in, $out);

##</code><code>##

my %kid;
for (@kids) {
    my $cpid = fork;
    defined $cpid or warn("Couldn't fork"), next;
    $cpid or do {    # child
        close $in or die $!;
        select $out;
        $| = 1;
        $_->();
        exit 0;
    };
    $kid{$cpid} = undef;
}

##</code><code>##

close $out or warn $!;
s/.$/??? says the child/, print while <$in>;
delete $kid{+wait} while %kid;