Why doesn't this code work and can't be killed with ctrl+z?

Question

Java

I took this code from one tutorial, tried to run it, but it still does not work safely.

import socket, time

host = socket.gethostbyname(socket.gethostname())# получает имя машины, на которой запущен питон и конвертирует в строку IpV4
port = 9873

clients = []

s = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)#создание самого сокета 
s.bind((host,port))#привязывает сокет к данному адресу

quit = False
print("[ Server Started ]")

while not quit:
  try:
    data, addr = s.recvfrom(1024)#получает инфу с сокета; возвращает список из инфы в 1024 байт и адреса 

    if addr not in clients:
      clients.append(addr)

    itsatime = time.strftime("%Y-%m-%d-%H.%M.%S", time.localtime())

    print("["+addr[0]+"]=["+str(addr[1])+"]=["+itsatime+"]/",end="")
    print(data.decode("utf-8"))

    for client in clients:
      if addr != client:
        s.sendto(data,client)#отправка сообщения
  except:	
    print("\n[ Server Stopped ]")
    quit = True
    
s.close()

that was the server and this is the client

import socket, threading, time



shutdown = False
join = False

def receving (name, sock):
  while not shutdown:
    try:
      while True:
        data, addr = sock.recvfrom(1024)
        print(data.decode("utf-8"))



        time.sleep(0.2)
    except:
      pass
host = socket.gethostbyname(socket.gethostname())
port = 0

server = ("192.168.0.101",9873)

s = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
s.bind((host,port))
s.setblocking(0)

alias = input("Name: ")

rT = threading.Thread(target = receving, args = ("RecvThread",s))
rT.start()

while shutdown == False:
  if join == False:
    s.sendto(("["+alias + "] => join chat ").encode("utf-8"),server)
    join = True
  else:
    try:
      message = input()

      if message != "":
        s.sendto(("["+alias + "] :: "+message).encode("utf-8"),server)
      
      time.sleep(0.2)
    except:
      s.sendto(("["+alias + "] <= left chat ").encode("utf-8"),server)
      shutdown = True

rT.join()
s.close()

When I launch this chat client and enter a name, it crashes and gives "OSError: [WinError 10051] An attempt was made to perform an operation on a socket while the network is down". How can it be cured?

Answer 1

Try updating IDEA

Answer 2

IMHO
If IDEA is licensed, either something is wrong with the JAVA config in the system, or something is wrong with Windows.
How long has it been? If you create a new project, is it the same?

Answer 3

you have a jamb in the server code, you have lost listen and accept.
Try reading this.