signotifyq_t
sqh = sigqhdralloc(sizeof (signotifyq_t),
((signotifyq_t *)sqp)->sn_snid = sid;
id.sn_index = (signotifyq_t *)sqp - SIGN_PTR(cp, 0);
#define SIGN_PTR(p, n) &((signotifyq_t *)(&p->p_signhdr[1]))[n];
signotifyq_t *snqp;