As an experiment, I tried this:

#!/usr/bin/perl

use strict;
use warnings;
use diagnostics;
use HTTP::GHTTP;

my $r = HTTP::GHTTP->new('http://www.cpan.org');

$r->set_async;
$r->set_chunksize(1024);
$r->prepare;

my $status;
while ($status = $r->process) {
    select(undef, undef, undef, 0.1);
}

die "An error occured" unless defined $status;

print $r->get_body;
[download]

updated: Fixed code and added die...