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BlockingIOError: [WinError 10035] A non-blocking socket operation could not be completed immediately

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
python
Domain
networking

Research direction

Start with multiconn-client.py at line 21, where start_connections calls sock.connect(server_addr), and reproduce the command shown against multiconn-server.py on Windows. Determine how the non-blocking connection is expected to complete and define the change needed for the example to run without the reported BlockingIOError.

Written by the indexing model from the issue text.

Description

When running the example multiconn-client and multiconn-server I get an error:

D:\git\PythonSocketProgramming\PythonSocketProgramming>python multiconn-client.py '127.0.0.1' 65432 1
starting connection 1 to ('127.0.0.1', 65432)
Traceback (most recent call last):
File "multiconn-client.py", line 60, in
start_connections( host, int(port), int(num_cons) )
File "multiconn-client.py", line 21, in start_connections
sock.connect( server_addr )
BlockingIOError: [WinError 10035] A non-blocking socket operation could not be completed immediately

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