menu_win - make and break menu window and subwindow associations
SYNOPSIS
#include <menu.h>
int set_menu_win(MENU *menu, WINDOW *win);
WINDOW *menu_win(const MENU *menu);
int set_menu_sub(MENU *menu, WINDOW *sub);
WINDOW *menu_sub(const MENU *menu);
int scale_menu(const MENU *menu, int *rows, int *columns);
DESCRIPTION
Every menu has an associated pair of curses windows. The menu window
displays any title and border associated with the window; the menu subwindow
displays the items of the menu that are currently available for selection.
The first four functions get and set those windows. It is not necessary to set
either window; by default, the driver code uses stdscr for both.
In the set_ functions, window argument of NULL is treated as though
it were stsdcr. A menu argument of NULL is treated as a request
to change the system default menu window or subwindow.
The function scale_menu returns the minimum size required for the
subwindow of menu.
RETURN VALUE
Routines that return pointers return NULL on error. Routines that return
an integer return one of the following error codes:
E_OK
The routine succeeded.
E_SYSTEM_ERROR
System error occurred (see errno).
E_BAD_ARGUMENT
Routine detected an incorrect or out-of-range argument.
