function listen-portrange ($range)
{	$port = $range; do 
	{ $port; $port +=1 
 
		$endpoint = new-object System.Net.IPEndPoint ([system.net.ipaddress]::any, $port) 
		$listener = new-object System.Net.Sockets.TcpListener $endpoint 
		$listener.start() 
		$listener.AcceptTcpClient()  # will block here until connection 
		$listener.stop() 
	} while ($port -le $range+1000)
}