MENU_DRIVER(3) BSD Library Functions Manual MENU_DRIVER(3)NAME
menu_driver -- main menu handling function
Curses Menu Library (libmenu, -lmenu)
menu_driver(MENU *menu, int c);
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:
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
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.
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>.
BSD September 10, 1999 BSD
Check Out this Related Man Page
menu_driver - command-processing loop of the menu system
int menu_driver(MENU *menu, int c);
Once a menu has been posted (displayed), you should funnel input events to it through menu_driver. This routine has three major input
cases; either the input is a menu navigation request, it's a printable ASCII character or it is the KEY_MOUSE special key associated with
an mouse event. The menu driver requests are as follows:
Move left to an item.
Move right to an item.
Move up to an item.
Move down to an item.
Scroll up a line.
Scroll down a line.
Scroll down a page.
Scroll up a page.
Move to the first item.
Move to the last item.
Move to the next item.
Move to the previous item.
Select/deselect an item.
Clear the menu pattern buffer.
Delete the previous character from the pattern buffer.
Move to the next item matching the pattern match.
Move to the previous item matching the pattern match.
If the second argument is a printable ASCII character, the code appends it to the pattern buffer and attempts to move to the next item
matching the new pattern. If there is no such match, menu_driver returns E_NO_MATCH and deletes the appended character from the buffer.
If the second argument is one of the above pre-defined requests, the corresponding action is performed.
If the second argument is the KEY_MOUSE special key, the associated mouse event is translated into one of the above pre-defined requests.
Currently only clicks in the user window (e.g. inside the menu display area or the decoration window) are handled. If you click above the
display region of the menu, a REQ_SCR_ULINE is generated, if you doubleclick a REQ_SCR_UPAGE is generated and if you tripleclick a
REQ_FIRST_ITEM is generated. If you click below the display region of the menu, a REQ_SCR_DLINE is generated, if you doubleclick a
REQ_SCR_DPAGE is generated and if you tripleclick a REQ_LAST_ITEM is generated. If you click at an item inside the display area of the
menu, the menu cursor is positioned to that item. If you double-click at an item a REQ_TOGGLE_ITEM is generated and E_UNKNOWN_COMMAND is
returned. This return value makes sense, because a double click usually means that an item-specific action should be returned. It's exactly
the purpose of this return value to signal that an application specific command should be executed. If a translation into a request was
done, menu_driver returns the result of this request. If you clicked outside the user window or the mouse event couldn't be translated
into a menu request an E_REQUEST_DENIED is returned.
If the second argument is neither printable ASCII nor one of the above pre-defined menu requests or KEY_MOUSE, the drive assumes it is an
application-specific command and returns E_UNKNOWN_COMMAND. Application-defined commands should be defined relative to MAX_COMMAND, the
maximum value of these pre-defined requests.
menu_driver return one of the following error codes:
E_OK The routine succeeded.
System error occurred (see errno).
Routine detected an incorrect or out-of-range argument.
Routine was called from an initialization or termination function.
The menu has not been posted.
The menu driver code saw an unknown request code.
Character failed to match.
The menu driver could not process the request.
SEE ALSO curses(3X), menu(3X).
The header file <menu.h> automatically includes the header files <curses.h>.
These routines emulate the System V menu library. They were not supported on Version 7 or BSD versions. The support for mouse events is
Juergen Pfeifer. Manual pages and adaptation for new curses by Eric S. Raymond.