This will unblock any threads that are sleeping in a call to
SDL_WaitAsyncIOResult for the specified queue, and cause them to return
from that function.
This can be useful when destroying a queue to make sure nothing is touching
it indefinitely. In this case, once this call completes, the caller should
take measures to make sure any previously-blocked threads have returned
from their wait and will not touch the queue again (perhaps by setting a
flag to tell the threads to terminate and then using SDL_WaitThread to
make sure they've done so).
Wake up any threads that are blocking in SDL_WaitAsyncIOResult.
This will unblock any threads that are sleeping in a call to SDL_WaitAsyncIOResult for the specified queue, and cause them to return from that function.
This can be useful when destroying a queue to make sure nothing is touching it indefinitely. In this case, once this call completes, the caller should take measures to make sure any previously-blocked threads have returned from their wait and will not touch the queue again (perhaps by setting a flag to tell the threads to terminate and then using SDL_WaitThread to make sure they've done so).