wwscroll1
int wwscroll1(struct ww *, int, int, int, int);
deleted = wwscroll1(w, row1, row2, 1, visible);
deleted = wwscroll1(w, row1, row2, -1, visible);
(void) wwscroll1(w, w->ww_i.t, w->ww_i.b, dir, 0);
(void) wwscroll1(w, w->ww_i.t,
(void) wwscroll1(w, w->ww_i.t,