udp_chat.py

#!/usr/bin/env python3

"""UDP Broadcast Sender"""

import socket
import sys
 
PORT = 33333
 
def udp_send_socket():
    udp_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    udp_socket.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
    return udp_socket

def send_runloop(sock, port=PORT):
    while True:
        data = input('>> ').strip()
        if sock.sendto(data.encode(), ('255.255.255.255', port)):
            print(f"[SEND] 255.255.255.255: '{data}'\n")
        if data == 'stop':
            break
 
    sock.close()
    print('Client stopped.')


if __name__ == '__main__':
    print(f'Sending on UDP port {PORT}')
    sock = udp_send_socket()
    send_runloop(sock)

==========================================================================

#!/usr/bin/env python3

"""UDP Broadcast Listener"""

import socket
import sys

PORT = 33333

def udp_listen_socket(host='', port=PORT):
    udp_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    udp_socket.bind((host, port))
    return udp_socket

def recv_runloop(sock):
    while True:
        data, addr = sock.recvfrom(1024)
        if data == 'stop':
            print('Client wants me to stop.')
            break
        else:
            print(f"[RECV] {addr[0]}: '{data}'\n")
     
    sock.close()
    print('Server stopped.')


if __name__ == '__main__':
    print(f'Listening on UDP port {PORT}')
    sock = udp_listen_socket()
    recv_runloop(sock)