#! perl -slw
use strict;
use threads;
use IO::Socket;

my $t1 = async {
    my $s = IO::Socket::INET->new( 'localhost:12345' );
    for ( 1 .. 1e6 ) {
        printf $s "Message %6d\n", $_;
        printf 'Sent and received: %s', scalar <$s>;
        sleep 1;
    }
};

my $t2 = async {
    my $s = IO::Socket::INET->new( 'localhost:54321' );
    for ( 1 .. 1e6 ) {
        printf $s "Message %6d\n", $_;
        printf 'Sent and received: %s', scalar <$s>;
        sleep 1;
    }
};

$_->join for $t1, $t2;