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@pedrominicz
Last active April 19, 2023 20:53
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Extremely simple "distributed echo server" server in Python (Telnet clients should be able to connect to it).
#!/usr/bin/env python3
import socket
# Read "distributed echo server" as "(distributed echo) server". The "server"
# is not "distributed" but the echos are "distributed" to every connected
# client.
# Connect to the server with `telnet localhost 5000`.
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.setblocking(False)
server.bind(('localhost', 5000))
server.listen(5)
connections = []
while True:
try:
connection, address = server.accept()
connection.setblocking(False)
connections.append(connection)
except BlockingIOError:
pass
for connection in connections:
try:
message = connection.recv(4096)
except BlockingIOError:
continue
for connection in connections:
connection.send(message)
@pucgenie
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This isn't Telnet, this is an Echo server (plus distribution of messages to all connected clients).

@pedrominicz
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This isn't Telnet, this is an Echo server (plus distribution of messages to all connected clients).

Fair enough. I'll update the description.

@QGB
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QGB commented Oct 5, 2022

Session stopped
- Press to exit tab
- Press R to restart session
- Press S to save terminal output to file

Network error: Connection refused

@QGB
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QGB commented Oct 5, 2022

telnet.exe 127.0.0.1 5000
Trying 127.0.0.1...                     
                                                                                                                          
telnet: Unable to connect to remote host: Connection refused                

@pedrominicz
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@QGB you are trying to connect to localhost but the script was binding your host name. I changed it to bind to localhost, so telnet localhost 5000 should work as expected.

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