import socket
import time
import threading

class Reader(threading.Thread):

    def __init__(this, udp_sock):
        threading.Thread.__init__(this)
        this.udp_sock = udp_sock
        this.running = 0
        
    def run(this):
        this.running = 1
        while this.running:
            try:
                text, addr = this.udp_sock.recvfrom(8000)
                print text
            except:
                pass
   
udp_sock=socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
udp_sock.bind(("", 5555))

reader = Reader(udp_sock)
reader.start()
while not reader.running:
    time.sleep(1.0)

while 1:
    time.sleep(1.0)
    print "!!"
    udp_sock.sendto("hi", ('localhost', 5556))
    print "   done."