void (*output_display_block_method) (struct window *, struct display_line *,
int, int, int, int, int, int, int);
int (*divider_height_method) (void);
void (*output_display_block_method) (struct window *, struct display_line *,
int, int, int, int, int, int, int);
int (*divider_height_method) (void);