mcast.py 文件源码

def sender(group):
    addrinfo = socket.getaddrinfo(group, None)[0]

    s = socket.socket(addrinfo[0], socket.SOCK_DGRAM)

    # Set Time-to-live (optional)
    ttl_bin = struct.pack('@i', MYTTL)
    if addrinfo[0] == socket.AF_INET: # IPv4
        s.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, ttl_bin)
    else:
        s.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_HOPS, ttl_bin)

    while True:
        data = repr(time.time())
        s.sendto(data + '\0', (addrinfo[4][0], MYPORT))
        time.sleep(1)