menu_post.3x man page
post_menu, unpost_menu — write or erase menus from associated subwindows
int post_menu(MENU *menu);
int unpost_menu(MENU *menu);
The function post_menu displays a menu to its associated subwindow. To trigger physical display of the subwindow, use refresh(3X) or some equivalent curses routine (the implicit doupdate triggered by an curses input request will do). post_menu resets the selection status of all items.
The function unpost_menu erases menu from its associated subwindow.
These routines return one of the following:
The routine succeeded.
System error occurred (see errno).
Routine detected an incorrect or out-of-range argument.
The menu has already been posted.
Routine was called from an initialization or termination function.
Menu is too large for its window. You should consider using set_menu_format to solve the problem.
The menu has not been posted.
No items are connected to the menu.
The header file <menu.h> automatically includes the header file <curses.h>.
These routines emulate the System V menu library. They were not supported on Version 7 or BSD versions.
Juergen Pfeifer. Manual pages and adaptation for new curses by Eric S. Raymond.