Is this design ok? A permanent tcpip connection is established. box 1 - one tcp server socket - visible to two threads thread 1 writes at arbitrary times thread 2 reads when something comes box 2 - one tcp client socket - visible to two threads thread 1 writes at arbitrary times thread 2 reads when something comes If this is a bad idea, I could use two socket pairs. Thanks for your advice. Mike. -- Michael D. Berger - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html