import socket
from time import *

# MCAST_GRP = '224.1.1.1'
# MCAST_PORT = 5007
MCAST_GRP = '224.1.1.22'
MCAST_PORT = 1234

# regarding socket.IP_MULTICAST_TTL
# ---------------------------------
# for all packets sent, after two hops on the network the packet will not 
# be re-sent/broadcast (see https://www.tldp.org/HOWTO/Multicast-HOWTO-6.html)
MULTICAST_TTL = 2

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
sock.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, MULTICAST_TTL)
while True:
    # sock.sendto("robot".encode("utf-8"), (MCAST_GRP, MCAST_PORT))
    t = ctime(time())
    sock.sendto(t.encode("utf-8"), (MCAST_GRP, MCAST_PORT))
    sleep(5)