bool wait_sync_flag(struct sync_flag *s, int seconds) {
struct timespec timeout;
clock_gettime(CLOCK_REALTIME, &timeout);
timeout.tv_sec += seconds;
bool wait_sync_flag(struct sync_flag *s, int seconds) {
struct timespec timeout;
clock_gettime(CLOCK_REALTIME, &timeout);
timeout.tv_sec += seconds;