python udp組播

# 發送組播
import socket
import struct
import time

mcast_group_ip = '234.2.2.2'
mcast_group_port = 23456

def sender():
    # 建立發送socket，和正常UDP數據包沒區別
    send_sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
    # 每十秒發送一遍消息
    while True:
        message = "this message send via mcast !"
        send_sock.sendto(message.encode(), (mcast_group_ip, mcast_group_port))
        print(f'{time.strftime("%Y-%m-%d %H:%M:%S", time.localtime())}: message send finish')
        time.sleep(2)

if __name__ == "__main__":
    sender()

# 接收組播
def receiver():
    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
    local_ip = socket.gethostbyname(socket.gethostname())  # 0.0.0.0
    sock.bind((local_ip, mcast_group_port))
    mreq = struct.pack("=4sl", socket.inet_aton(mcast_group_ip), socket.INADDR_ANY)
    sock.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)

    while True:
        time.sleep(0.1)
        try:
            message, addr = sock.recvfrom(1024)
            print(
                f'{time.strftime("%Y-%m-%d %H:%M:%S", time.localtime())}: Receive data from {addr}: {message.decode()}')
        except:
            print("while receive message error occur")

if __name__ == "__main__":
    receiver()