OSError: [WinError 10038] An operation was attempted on something that is not a socket - Python sockets?

Question

client-side:

import select
import socket
import sys

from pip._vendor.distlib.compat import raw_input

you = str(raw_input("Please Input your name: "))


def chat_client():
    if len(sys.argv) < 3:
        print('Usage : python chat_client.py hostname port')
        sys.exit()

    host = sys.argv[1]
    port = int(sys.argv[2])

    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.settimeout(2)

    # connect to remote host
    try:
        s.connect((host, port))

    except:
        print('Unable to connect')
        sys.exit()

    print('Connected to remote host. You can start sending messages')
    sys.stdout.write(you + "=> ")
    sys.stdout.flush()

    while 1:
        socket_list = [sys.stdin, s]

        # Get the list sockets which are readable
        read_sockets, write_sockets, error_sockets = select.select(socket_list, [], [])

        for sock in read_sockets:
            if sock == s:
                # incoming message from remote server, s
                data = sock.recv(4096)
                if not data:
                    print('\nDisconnected from chat server')
                    sys.exit()
                else:
                    # print data
                    sys.stdout.write(data)
                    sys.stdout.write(you + "=> ")
                    sys.stdout.flush()

            else:
                # user entered a message
                msg = you + ":" + sys.stdin.readline()
                s.send(msg)
                sys.stdout.write(you + "=> ")
                sys.stdout.flush()


if __name__ == "__main__":
    sys.exit(chat_client())

server side:

import sys, socket, select

from pip._vendor.distlib.compat import raw_input

HOST = str(raw_input("Please input IP address :  "))

SOCKET_LIST = []
RECV_BUFFER = 4096
PORT = 9009


def chat_server():
    server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    server_socket.bind((HOST, PORT))
    server_socket.listen(10)

    # add server socket object to the list of readable connections
    SOCKET_LIST.append(server_socket)

    print("Chat server started on port " + str(PORT))

    while 1:

        # get the list sockets which are ready to be read through select
        # 4th arg, time_out  = 0 : poll and never block
        ready_to_read, ready_to_write, in_error = select.select(SOCKET_LIST, [], [], 0)

        for sock in ready_to_read:
            # a new connection request recieved
            if sock == server_socket:
                sockfd, addr = server_socket.accept()
                SOCKET_LIST.append(sockfd)
                print("Client (%s, %s) connected" % addr)

                broadcast(server_socket, sockfd, "[%s:%s] entered ourchatting room\n" % addr)

            # a message from a client, not a new connection
            else:
                # process data recieved from client, 
                try:
                    # receiving data from the socket.
                    data = sock.recv(RECV_BUFFER)
                    if data:
                        # there is something in the socket
                        broadcast(server_socket, sock, "\r" + data)
                    else:
                        # remove the socket that's broken    
                        if sock in SOCKET_LIST:
                            SOCKET_LIST.remove(sock)

                        # at this stage, no data means probably theconnection has been broken
                        broadcast(server_socket, sock, "Client (%s, %s)is offline\n" % addr)

                        # exception
                except:
                    broadcast(server_socket, sock, "Client (%s, %s) isoffline\n" % addr)
                    continue

    server_socket.close()


# broadcast chat messages to all connected clients
def broadcast(server_socket, sock, message):
    for socket in SOCKET_LIST:
        # send the message only to peer
        if socket != server_socket and socket != sock:
            try:
                socket.send(message)
            except:
                # broken socket connection
                socket.close()
                # broken socket, remove it
                if socket in SOCKET_LIST:
                    SOCKET_LIST.remove(socket)


if __name__ == "__main__":
    sys.exit(chat_server())

after running the client I recived the following error:

Traceback (most recent call last): File "C:/Users/David Bialik/PycharmProjects/Ser/chat_client.py", line 63, in sys.exit(chat_client()) File "C:/Users/David Bialik/PycharmProjects/Ser/chat_client.py", line 39, in chat_client read_sockets, write_sockets, error_sockets = select.select(socket_list, [], []) OSError: [WinError 10038] An operation was attempted on something that is not a socket

I'm wondering why it happens

Answer 1

The error is caused by the following lines

socket_list = [sys.stdin, s] #<----here
read_sockets, write_sockets, error_sockets = select.select(socket_list, [], [])

WinError suggests you're on Windows. sys.stdin can be treated as a socket on *nix platforms but not on Windows. So all you have to do is to replace sys.stdin with socket.socket()

So it becomes socket_list = [socket.socket(), s]