ref: 7e2eb5f0bb283b6330eb7a09be345ad1754afc4e
dir: /sys/src/cmd/python/Demo/sockets/broadcast.py/
# Send UDP broadcast packets
MYPORT = 50000
import sys, time
from socket import *
s = socket(AF_INET, SOCK_DGRAM)
s.bind(('', 0))
s.setsockopt(SOL_SOCKET, SO_BROADCAST, 1)
while 1:
data = repr(time.time()) + '\n'
s.sendto(data, ('<broadcast>', MYPORT))
time.sleep(2)