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Python socket library: OSError: [WinError 10057] A request to send or receive data was disallowed because the socket is not connected

OSError: [WinError 10057] A request to send or receive data was disallowed because the socket is not connected and (when sending on a datagram socket using a sendto call) no address was supplied.
I am getting the above error..My server and client can send and receive their first messages but I get this error if I try to send more than one message.
My Server Code is here
import socket
import threading
import time
from tkinter import *
#functions
def t_recv():
r = threading.Thread(target=recv)
r.start()
def recv():
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as listensocket:
port = 5354
maxconnections = 9
ip = socket.gethostbyname(socket.gethostname())
print(ip)
server = (ip, port)
FORMAT = 'utf-8'
listensocket.bind((server))
listensocket.listen(maxconnections)
(clientsocket, address) = listensocket.accept()
msg = f'\[ALERT\] {address} has joined the chat.'
lstbox.insert(0, msg)
while True:
sendermessage = clientsocket.recv(1024).decode(FORMAT)
if not sendermessage == "":
time.sleep(3)
lstbox.insert(0, 'Client: ' +sendermessage)
def t_sendmsg():
s = threading.Thread(target=sendmsg)
s.start()
at = 0
def sendmsg():
global at
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as g:
hostname = 'Lenovo-PC'
port = 5986
if at==0:
g.connect((hostname, port))
msg = messagebox.get()
lstbox.insert(0, 'You: ' +msg)
g.send(msg.encode())
at += 1
else:
msg = messagebox.get()
lstbox.insert(0, 'You: ' +msg)
g.send(msg.encode())
And my client code is same with minor difference
import socket
import time
import threading
from tkinter import *
#functions
def t_recv():
r = threading.Thread(target=recv)
r.start()
def recv():
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as listensocket:
port = 5986
maxconnections = 9
ip = socket.gethostname()
print(ip)
FORMAT = 'utf-8'
host = 'MY_IP' # My actual ip is there in the code
listensocket.bind((host, port))
listensocket.listen(maxconnections)
(clientsocket, address) = listensocket.accept()
while True:
sendermessage = clientsocket.recv(1024).decode(FORMAT)
if not sendermessage == "":
time.sleep(3)
lstbox.insert(0, 'Server: ' +sendermessage)
def t_sendmsg():
s = threading.Thread(target=sendmsg)
s.start()
at = 0
def sendmsg():
global at
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as g:
hostname = 'Lenovo-PC'
port = 5354
if at==0:
g.connect((hostname, port))
msg = messagebox.get()
lstbox.insert(0, 'You: ' +msg)
g.send(msg.encode())
at += 1
else:
msg = messagebox.get()
lstbox.insert(0, 'You: ' +msg)
g.send(msg.encode())
Please let me know what changes are required to be made in order to make it run for every message.
I tried to put
g.connect((hostname, port))
the above line in the loop so that it will connect every time loop iterates. But it did not help.

with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as g:
...
if at==0:
g.connect((hostname, port))
...
g.send(msg.encode())
at += 1
else:
...
g.send(msg.encode())
In the if at==0 condition it connects to the server, in the else part not. But is still trying to send something on the not connected socket.

How to connect to Python socket server from another network

I'm new to socket programming and I'm trying to make a server with socket module. When working on a local network it works perfectly fine, but the problem comes when I'm trying to run it and connect from two different networks. I've tried many things that I saw on SO and the internet in general.
Server code:
import socket
import threading
SERVER = socket.gethostbyname('')
PORT = 12345
ADDR = (SERVER, PORT)
HEADER = 64
FORMAT = 'utf-8'
DISCONNECT_MESSAGE = '!DISCONNECT'
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.bind(ADDR)
def handle_client(conn, addr):
print(f'[NEW CONNECTION] {addr} connected.')
print(f'[ACTIVE CONNECTIONS] {threading.active_count() - 1}')
connected = True
while connected:
msg_lenght = conn.recv(HEADER).decode(FORMAT)
if msg_lenght:
msg_lenght = int(msg_lenght)
msg = conn.recv(msg_lenght).decode(FORMAT)
if msg == DISCONNECT_MESSAGE:
connected = False
print(f'[MESSAGE RECIEVED] FROM: {addr}; Message: {msg}')
conn.send('Message received!'.encode(FORMAT))
conn.close()
def start():
server.listen()
print(f'[LISTENING] Server is listening on {SERVER}')
while True:
conn, addr = server.accept()
thread = threading.Thread(target=handle_client, args=(conn, addr))
thread.start()
print(f'IP Address: {SERVER}')
print('[STARTING] Server is starting...')
start()
Client code:
import socket
SERVER = input('IP Address: ')
PORT = 5050
ADDR = (SERVER, PORT)
HEADER = 64
FORMAT = 'utf-8'
DISCONNECT_MESSAGE = '!DISCONNECT'
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client.connect(ADDR)
def send(msg):
message = msg.encode(FORMAT)
msg_lenght = len(message)
send_lenght = str(msg_lenght).encode(FORMAT)
send_lenght += b' ' * (HEADER - len(send_lenght))
client.send(send_lenght)
client.send(message)
while True:
user_Input = input('Message: ')
send(user_Input)
if user_Input == DISCONNECT_MESSAGE:
break
I tried making "rules" on the firewall that should make my port public or something. I have also tried different addresses because I was not sure which one to use.
Thanks in advance!

Python socket - how to save data from two clients separately

Here's the code, I wonder how to save the messages separately.
It can only get and send messages back to client. But I can't distinguish which are from client 1 and which are from client 2. Is there any way to save these messages into separate list or something else? so that I can distinguish them
Client 1:
import socket
import sys
messages = [b'This is client 1',
b'It is a good day!',
]
server_address = ('localhost', 1234)
socks = [ socket.socket(socket.AF_INET,
socket.SOCK_STREAM)
for i in range(1)]
print('connecting to %s port %s' % server_address)
for s in socks:
s.connect(server_address)
for message in messages:
for s in socks:
s.send(message)
for s in socks:
data = s.recv(1024)
print(data.decode())
if not data:
print(sys.stderr, 'closing socket', s.getsockname())
Client 2:
import socket
import sys
messages = [b'This is client 2',
b'It is raining today',
]
server_address = ('localhost', 5678)
socks = [ socket.socket(socket.AF_INET,
socket.SOCK_STREAM)
for i in range(1)]
print('connecting to %s port %s' % server_address)
for s in socks:
s.connect(server_address)
for message in messages:
for s in socks:
s.send(message)
for s in socks:
data = s.recv(1024)
print(data.decode())
if not data:
print(sys.stderr, 'closing socket', s.getsockname())
Server:
import selectors
import socket
sel = selectors.DefaultSelector()
def accept(sock, mask):
conn, addr = sock.accept()
print('accepted', conn, 'from', addr)
conn.setblocking(False)
sel.register(conn, selectors.EVENT_READ, read)
def read(conn, mask):
data = conn.recv(1000)
if data:
conn.send(data)
else:
print('closing', conn)
sel.unregister(conn)
conn.close()
sock = socket.socket()
sock.bind(('localhost', int(input())))
sock.listen(1)
sock.setblocking(False)
sel.register(sock, selectors.EVENT_READ, accept)
while True:
events = sel.select()
for key, mask in events:
callback = key.data
callback(key.fileobj, mask)

If you want to validate the ip on the network layer then you can use the variable addr that you create when you accept the connection.
However when you are doing this with multiple clients on the same host then it will not work since the ip is the same.
This will also not work if you are behind a NAT, because you would just get the IP of the nearest router in your network.
Another solution would be to validate the client on the application layer and simply give the client an identification value that you pass into the message that you send from the client.

Socket Error Python

I had the following code and I cannot observe the behaivour of server and receiver client because client sender pops error continiously. How can I handle this?
Error: An existing connection is forced to shut down by a remote computer
Client Sender
import socket
import sys
serverName = 'localhost'
serverPort = 12000
while True:
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.connect((serverName, serverPort))
f = open("sentfile.txt")
l = f.read(2097152)
while(l):
l_bytes = bytes(l, "utf-8")
s.sendall(l_bytes)
Server
import socket
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind(('localhost', 12000))
s.listen(1)
print ("The server is ready")
conn, addr = s.accept()
with conn:
print('Connected by ', addr)
while True:
data = conn.recv(2097152)
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as p:
p.bind(('localhost', 1000))
conn2, addr2 = p.accept()
with conn2:
conn2.sendall(data)
Client Receiver
import socket
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind(('localhost', 1000))
s.listen(1)
conn, addr = s.accept()
with conn:
while True:
f = open('receivedfile.txt', 'ba')
data = connRev(2097152)
f.write(data)
f.close()

first you have to import Socket module. Then use the function getaddrinfo().

how to create a UDP server that will listen on multiple ports in python?

this is my server:
import socket
for port in range(33,128):
server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
server_socket.bind(('0.0.0.0', port))
while True:
(client_name, client_adress) = server_socket.recvfrom(1024)
print chr(port)
server_socket.close()
this is my client:
import socket
message = raw_input("Enter a message: ")
for letter in message:
my_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
while True:
my_socket.sendto("", ('127.0.0.1', ord(letter)))
(data, remote_adress) = my_socket.recvfrom(1024)
my_socket.close()
print 'The server sent: ' + data

I'm not very good in python, but I think you should save your sockets to list inside for and then use select function in infinite loop outside for
import socket
import select
sockets = []
for port in range(33,128):
server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
server_socket.bind(('0.0.0.0', port))
sockets.append(server_socket)
empty = []
while True:
readable, writable, exceptional = select.select(sockets, empty, empty)
for s in readable:
(client_data, client_address) = s.recvfrom(1024)
print client_address, client_data
for s in sockets:
s.close()