Comment by deathanatos

How is what you're describing not just Nagle's algorithm?

If you mean TCP_NODELAY, you should use it with TCP_CORK, which prevents partial frames. TCP_CORK the socket, do your writes to the kernel via send, and then once you have an application level "message" ready to send out — i.e., once you're at the point where you're going to go to sleep and wait for the other end to respond, unset TCP_CORK & then go back to your event loop & sleep. The "uncork" at the end + nodelay sends the final partial frame, if there is one.