Hi all, I have a real time application with a couple of threads. One thread is waiting on a select() call (with timeout) for data coming in from a UDP Ethernet socket. Once it gets data it does some computation and finally leads to the writing of data on the UDP socket. The (simplified) code for this real time thread is: void *thread_func_A(void *arg) { while (1) { rc = select(...); // Read socket with timeout_value); if (rc > 0) { recv(.., data, .. ); // recv data from socket compute(data, data2); // Compute data and modify them to data2 send(..., data2, ...); // Send data2 to socket } } } This works fine. Now I have the need that another real time thread B should also be able to trigger the "select()" in the thread_func_A() above. This means, I should add a suitable inter-process-communication between thread A and B that can be used with select() as well. Having this, the thread A can be triggered by the socket or by the IPC from thread B by adding two file desciptors to the readfds of select(). My question is now: What kind of IPC is preferred here? The only IPC I see is a local socket communication, however this looks like a huge overhead for triggering... Both, threads A and B are real time threads, thus any IPC in use should be supported by the RT_PREEMPT patch. Setup: PC (Core2Quad, kernel 2.6.31.2-rt13) Thanks for any feedback on this question. Regards Mathias -- Mathias Koehrer mathias_koehrer@xxxxxxxx Traumziele - von Beschreibung bis Buchung jetzt kompakt auf den Reise-Seiten von Arcor.de! http://www.arcor.de/rd/footer.reise -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html