👀 Views: 79 💬 Answers: 1 📅 Created: 2025-06-07

python sockets select Python

I need some guidance on I'm stuck on something that should probably be simple. I'm working on a TCP server-client application in Python 3.9, and I'm working with a frustrating scenario where the client receives a 'Connection Refused' behavior when trying to connect to the server. The server is set up to listen on `localhost:12345`, and I am using the `select()` function to handle multiple connections. I've ensured that the server is running and listening before the client attempts to connect. Here's the server code: ```python import socket import select HOST = 'localhost' PORT = 12345 server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM) server_socket.bind((HOST, PORT)) server_socket.listen(5) sockets_list = [server_socket] while True: read_sockets, _, _ = select.select(sockets_list, [], []) for sock in read_sockets: if sock == server_socket: client_socket, address = server_socket.accept() sockets_list.append(client_socket) print(f'Accepted connection from {address}') else: # handle other sockets pass ``` And here's the client code: ```python import socket HOST = 'localhost' PORT = 12345 client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM) try: client_socket.connect((HOST, PORT)) print('Connected to the server!') except ConnectionRefusedError: print('Connection refused. Is the server running?') ``` When I run the server and then the client, I get the 'Connection refused' behavior. I've checked my firewall settings and allowed `localhost` connections, which seems fine. I even tried changing the port number, but the question continues. Could there be an scenario with how I'm using `select()`? I suspect it might be a race condition, but I'm not sure how to address that effectively. Any insights into what might be going wrong here? My development environment is Linux. For context: I'm using Python on Ubuntu 22.04. Has anyone dealt with something similar?