vaccess
if (vaccess(VNON, mq->mq_mode, mq->mq_euid, mq->mq_egid,
int vaccess(enum vtype, mode_t, uid_t, gid_t, mode_t, struct ucred *);
if (vaccess(p->v_access, READ))
if ((p = vlookup(s)) && vaccess(p->v_access, READ)) {
static int vaccess(unsigned, unsigned);
if (!vaccess(p->v_access, WRITE)) {