grid_view_delete_lines
grid_view_delete_lines(gd, s->cy, ny, bg);
grid_view_delete_lines(gd, s->cy, ny, bg);
grid_view_delete_lines(gd, oldy - available,
grid_view_delete_lines(gd, 0, available, 8);
void grid_view_delete_lines(struct grid *, u_int, u_int, u_int);