schedctl_t
((((schedctl_t *)(p))->sc_nopreempt = 1), 0))
((((schedctl_t *)(p))->sc_nopreempt = 0), \
(((schedctl_t *)(p))->sc_yield? (yield(), 0) : 0)))
schedctl_t *schedctl_init(void);
schedctl_t *schedctl_lookup(void);
schedctl_t *
return ((scp == NULL)? NULL : (schedctl_t *)&scp->sc_preemptctl);