Python socket sends the first message but nothing afterward

Question

My socket sends the first message but nothing afterward.
The output in the server:

What do you want to send?

lol

The client receives:

From localhost got message:

lol

And then it doesn't want to send anything else. I don't get the what do you want to send printed anymore.

My code:

server.py file:

#!/usr/bin/python3
import socket

# create a socket object
serversocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

# get local machine name
host = socket.gethostname()
print ("got host name:", host)

port = 9996
print("connecting on port:", port)

# bind to the port
serversocket.bind((host, port))
print("binding host and port")

# queue up to 5 requests
serversocket.listen(5)
print("Waiting for connection")

while True:
    clientsocket, addr = serversocket.accept()
    msg = input("what do you want to send?\n")
    clientsocket.send(msg.encode('ascii'))

client.py file:

#!/usr/bin/python3
import socket # create a socket object

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) # get local machine

# name
host = socket.gethostname()
port = 9996 # connection to hostname on the port.

s.connect((host, port)) # Receive no more than 1024 bytes

while True:
    msg = s.recv(1024)
    print(msg.decode("ascii"))

The client only connects once (OK) but the server waits for an incoming connection every start of the `while` loop. — timgeb, Oct 22 '18 at 07:08
OH! im so dumb! thanks alot! i finally got this working for the first time. — GottaAimHigherPal, Oct 22 '18 at 07:11

score 1 · Answer 1 · answered Oct 22 '18 at 07:18

The client only connects once (OK) but the server waits for an incoming connection every start of the while loop.

Since there are no more connection requests by a client, the server will freeze on the second iteration.

If you just want to handle a single client, move clientsocket, addr = serversocket.accept() before the while loop. If you want to handle multiple clients, the standard way is to have the server accept connections inside the while loop and spawn a thread for each client.

You can also use coroutines, but that may be a bit overkill if you are just starting out.

Python socket sends the first message but nothing afterward

1 Answers1