MENU_DRIVER(3)

NAME
menu_driver - main menu handling function

LIBRARY
libmenu

SYNOPSIS
#include <menu.h>
int
menu_driver(MENU *menu, int c);

DESCRIPTION
The menu_driver() function is the guts of the menu system. It takes the commands passed by c parameter and performs the requested action on the menu given. The following commands may be given to the menu driver:

Command
    Action
REQ_LEFT_ITEM
    Sets the new current item to be the item to the left of the current item.
REQ_RIGHT_ITEM
    Sets the new current item to be the item to the rights of the current item.
REQ_UP_ITEM
    Sets the new current item to be the item above the current item.
REQ_DOWN_ITEM
    Sets the new current item to be the item below the current item.
REQ_SCR_ULINE
    Scroll the menu one line towards the bottom of the menu window. The new current item becomes the item immediately above the current item.
REQ_SCR_DLINE
    Scroll the menu one line towards the top of the menu window. The new current item becomes the item immediately below the current item.
REQ_SCR_DPAGE
    Scroll the menu one page towards the bottom of the menu window.
REQ_SCR_UPAGE
    Scroll the menu one page towards the top of the menu window.
REQ_FIRST_ITEM
    Set the current item to be the first item in the menu.
REQ_LAST_ITEM
    Set the current item to be the last item in the menu.
REQ_NEXT_ITEM
    Set the new current item to be the next item in the item array after the current item.
REQ_PREV_ITEM
    Set the new current item to be the item before the current item in the items array.
REQ_TOGGLE_ITEM
    If the item is selectable then toggle the item's value.
REQ_CLEAR_PATTERN
    Clear all the characters currently in the menu's pattern buffer.
REQ_BACK_PATTERN
    Remove the last character from the pattern buffer.
REQ_NEXT_MATCH
    Attempt to find the next item that matches the pattern buffer.
REQ_PREV_MATCH
    Attempt to find the previous item that matches the pattern buffer.
If menu_driver() is passed a command that is greater than MAX_COMMAND then the command passed is assumed to be a user defined command and menu_driver() returns E_UNKNOWN_COMMAND. Otherwise if the command is a printable character then the character represented by the command is placed at the end of the pattern buffer and an attempt is made to match the pattern buffer against the items in the menu.

RETURN VALUES
The functions return one of the following error values:

E_OK
    The function was successful.
E_SYSTEM_ERROR
    There was a system error during the call.
E_BAD_ARGUMENT
    One or more of the arguments passed to the function was incorrect.
E_NOT_POSTED
    The menu is not posted.
E_UNKNOWN_COMMAND
    The menu driver does not recognize the request passed to it.
E_NO_MATCH
    The character search failed to find a match.
E_NOT_CONNECTED
    The item is not connected to a menu.
E_REQUEST_DENIED
    The menu driver could not process the request.

SEE ALSO
curses(3), menus(3)

NOTES
The header <menu.h> automatically includes both <curses.h> and <eti.h>.