Unblock recvfrom when socket is closed

Question

Let\'s say I start a thread to receive on a port. The socket call will block on recvfrom. Then, somehow in another thread, I close the socket.

On Windows, this will

Answer 1

Call shutdown(sock, SHUT_RDWR) on the socket, then wait for the thread to exit. (i.e. pthread_join).

You would think that close() would unblock the recvfrom(), but it doesn't on linux.