+uloop.fd_add(udp, function(ufd, events)
+ local words, msg_or_ip, port_or_nil = ufd:receivefrom()
+ print('Recv UDP packet from '..msg_or_ip..':'..port_or_nil..' : '..words)
+end, uloop.ULOOP_READ)
+
+udp_send_timer = uloop.timer(
+ function()
+ local s = socket.udp()
+ local words = 'Hello!'
+ print('Send UDP packet to 127.0.0.1:8080 :'..words)
+ s:sendto(words, '127.0.0.1', 8080)
+ s:close()
+
+ udp_send_timer:set(1000)
+ end, 3000
+)
+