hat_dup
int hat_dup(struct hat *, struct hat *, caddr_t, size_t, uint_t);
(void) hat_dup(as->a_hat, newas->a_hat, NULL, 0, HAT_DUP_SRD);
error = hat_dup(as->a_hat, newas->a_hat, NULL, 0, HAT_DUP_ALL);