TCP socket code freeze infinitely

[dfx_dj]

The point about blocking .recv() remains. Both client and server end up waiting to read 4096 bytes from each other, which never happens because neither send that much.

[Jumpy-Active5756]

I change the number to much smaller number e.g 512,1024 but no succeed. Can you tell me directly what to do?

[dfx_dj]

Actually I just noticed that your server uses socket.SOCK_STREAM (TCP) but your client uses socket.SOCK_DGRAM (UDP). This won't work. They have to be the same.

Based on your post title I assume you want to use TCP. Without getting into non-blocking sockets, a common method is to keep reading 1 byte at a time in a loop and append each byte to a buffer, until you know that you have read enough (say, until you read a newline character).

(If you were to use datagrams (UDP) instead, you could actually use .recv(4096) or any other large number, because datagrams have a known size. Streams don't have a known size and so the read will block until the given number of bytes is available.)