utoppy_current_ptr
err = uiomove(utoppy_current_ptr(sc->sc_out_data), len, uio);
uwfp = utoppy_current_ptr(sc->sc_out_data);
p = utoppy_current_ptr(h);
p = utoppy_current_ptr(h);
p = utoppy_current_ptr(h);
p = utoppy_current_ptr(h);
p = utoppy_current_ptr(h);
p = utoppy_current_ptr(h);