static inline pthread_descr dequeue(pthread_queue * q)
static inline pthread_descr dequeue(pthread_descr * q)
static inline pthread_descr dequeue(pthread_queue * q){  pthread_descr th;  th = q->head;  if (th != NULL) {    q->head = th->p_nextwaiting;    if (q->head == NULL) q->tail = NULL;    th->p_nextwaiting = NULL;  }  return th;}