           menu_hook - set hooks for automatic invocation by applica-
           tions

## SYNOPSIS

           #include
           int set_item_init(MENU *menu, void (*func)(MENU *));
           void (*)(MENU *) item_init(const MENU *menu);
           int set_item_term(MENU *menu, void (*func)(MENU *));
           void (*)(MENU *) item_term(const MENU *menu);
           int set_menu_init(MENU *menu, void (*func)(MENU *));
           void (*)(MENU *) menu_init(const MENU *menu);
           int set_menu_term(MENU *menu, void (*func)(MENU *));
           void (*)(MENU *) menu_term(const MENU *menu);

## DESCRIPTION

           These functions make it possible to set hook functions  to
           be called at various points in the automatic processing of
           input event codes by menu_driver.

           The function set_item_init sets a hook  to  be  called  at
           menu-post  time  and  each  time the selected item changes
           (after the change).  item_init returns  the  current  item
           init hook, if any (NULL if there is no such hook).

           The  function  set_item_term  sets  a hook to be called at
           menu-unpost time and each time the selected  item  changes
           (before  the  change).  item_term returns the current item
           term hook, if any (NULL if there is no such hook).

           The function set_menu_init sets a hook  to  be  called  at
           menu-post  time  and  just  after  the top row on the menu
           changes once it is posted.  menu_init returns the  current
           menu init hook, if any (NULL if there is no such hook).

           The  function  set_menu_term  sets  a hook to be called at
           menu-unpost time and just before the top row on  the  menu
           changes  once it is posted.  menu_term returns the current
           menu term hook, if any (NULL if there is no such hook).

## RETURN VALUE

           Routines that return pointers return NULL on error.  Other
           routines return one of the following:

           E_OK The routine succeeded.

           E_SYSTEM_ERROR
                System error occurred (see errno).

## SEE ALSO

           curses(3X), menu(3X).

## NOTES

## PORTABILITY

           These routines emulate the System V  menu  library.   They
           were not supported on Version 7 or BSD versions.

## AUTHORS

           Juergen  Pfeifer.   Manual  pages  and  adaptation for new
           curses by Eric S. Raymond.