Python使用socket实现组播与发送二进制数据

import socket
import struct

# 1.创建一个套接字
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

multicast_group = ('224.3.29.71', 10000)
sock.settimeout(10)

ttl = struct.pack('b', 1)#本博主数据结构与算法第10篇对struct二进制结构体进行介绍
sock.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, ttl)

try:
    msg = "群发的消息，你不必回".encode('UTF-8')
    sent = sock.sendto(msg, multicast_group)
    while True:
        try:
            data, server = sock.recvfrom(1024)
        except socket.timeout:
            print('time out')
            break
        else:
            print(data, server)
finally:
    sock.close()

import socket
import struct

multicast_group = '224.3.29.71'
server_address = ('', 10000)

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.bind(server_address)

group = socket.inet_aton(multicast_group)
mreq = struct.pack('4sL', group, socket.INADDR_ANY)

sock.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)

while True:
    data, address = sock.recvfrom(1024)
    print(data.decode('UTF-8'), address)
    sock.sendto('组播消息已经收到'.encode('UTF-8'), address)