sleepq_signal
sleepq_signal(c, SLEEPQ_SLEEP, 0, 0);
sleepq_signal(task, SLEEPQ_SLEEP, 0, 0);
sleepq_signal(wchan, SLEEPQ_SLEEP, 0, 0);
sleepq_signal(wchan, SLEEPQ_SLEEP, 0, 0);
sleepq_signal(c, SLEEPQ_SLEEP, 0, 0);
sleepq_signal(cvp, SLEEPQ_CONDVAR | SLEEPQ_DROP, 0, 0);
sleepq_signal(ident, SLEEPQ_SLEEP | SLEEPQ_DROP, 0, 0);
sleepq_signal(ident, SLEEPQ_SLEEP | SLEEPQ_UNFAIR | SLEEPQ_DROP, 0, 0);
void sleepq_signal(const void *wchan, int flags, int pri, int queue);