Hi Gilles, I think some regression slipped into the rt-pthread lib. This example no longer works on my box (thread is not executed): #include #include #include void *thread(void *arg) { printf("thread\n"); return 0; } main() { pthread_t thr; mlockall(MCL_CURRENT|MCL_FUTURE); printf("create = %d\n", pthread_create(&thr, NULL, thread, NULL)); pause(); } This also explains why the cyclic test is broken. Jan