+struct Map;
+
+
+
+/* Learn from "file" the largest line length (pointed to by "linemax_p") and
+ * (pointed to by "n_lines_p" if it is not set to NULL) the number of lines.
+ */
+extern void textfile_sizes(FILE * file, uint16_t * linemax_p,
+ uint16_t * n_lines_p);
+
+
+
+/* Update game log by appending "text", or by appending a "." if "text" is the
+ * same as the last one passed.
+ */
+extern void update_log(struct World * world, char * text);
+
+
+
+/* Return the offset necessary to center "map" on position "pos" in a frame of
+ * "framesize.
+ */
+extern uint16_t center_offset(uint16_t pos, uint16_t mapsize,
+ uint16_t framesize);
+
+
+
+/* Record last player "action" in game record file "record, increment the game
+ * turn and trigger enemy movement.
+ */
+extern void turn_over(struct World * world, char action);
+
+
+
+/* Save current game data to file "savefile". */
+extern void save_game(struct World * world);
+
+
+
+/* Toggle display of a window "win".
+ *
+ * Return 0 on success, 1 on (ncurses pad/window memory allocation) error.
+ */
+extern uint8_t toggle_window(struct WinMeta * win_meta, struct Win * win);
+
+
+
+/* Try to scroll virtual screen left ("dir" = "-") or right ("dir" = "+"),
+ * subject to the limitations provided by the window manager via
+ * reset_pad_offset().
+ */
+extern void scroll_pad(struct WinMeta * win_meta, char dir);
+
+
+
+/* Try to grow or shrink the active window horizontally ("change" = "*"/"_") or
+ * vertically ("change = "+"/"-") by one cell size, subject to the limitations
+ * provided by the window manager via resize_active_win().
+ *
+ * Return 0 on success, 1 on (ncurses pad/window memory allocation) error.
+ */
+extern uint8_t growshrink_active_window(struct WinMeta * win_meta, char change);
+
+
+
+/* Return a random position on the map "map" that is passable (as determined by
+ * is_passable().
+ */
+extern struct yx_uint16 find_passable_pos(struct Map * map);
+
+
+
+/* Call some meta game / window management actions dependent on key. If the
+ * "quit" action is called, return 1 only instead of doing anything directly.
+ */
+extern uint8_t meta_keys(int key, struct World * world);
+