* 1 - memory allocation error (of ncurses' pads/windows, or scroll hint texts)
* 2 - activity forces virtual screen to grow beyond width of 2^16 cells
*
+ * TODO: Expose less internals to the API.
+ *
* TODO: Think up a more intuitive window positioning algorithm or at least make
* the chain that windows are positioned by visible.
*/
-/* Move active window forwards ("dir" == "f") or backwards ("dir" == "b").
+/* Move active window forwards ("dir" == "f") or backwards (any other "dir").
* Wrap around in the window chain if start / end of it is met. Does nothing if
* no window is active.
*/