menu_driver

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUE
SEE ALSO
NOTES
PORTABILITY
AUTHORS

NAME

menu_driver - command-processing loop of the menu system

SYNOPSIS

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

DESCRIPTION

Once a menu has been posted (displayed), you should funnel input events to it through menu_driver. This routine has two major input cases; either the input is a menu navigation request or it’s a printable ASCII character. The menu driver requests are as follows:
REQ_LEFT_ITEM

Move left to an item.

REQ_RIGHT_ITEM

Move right to an item.

REQ_UP_ITEM

Move up to an item.

REQ_DOWN_ITEM

Move down to an item.

REQ_SCR_ULINE

Scroll up a line.

REQ_SCR_DLINE

Scroll down a line.

REQ_SCR_DPAGE

Scroll down a page.

REQ_SCR_UPAGE

Scroll up a page.

REQ_FIRST_ITEM

Move to the first item.

REQ_LAST_ITEM

Move to the last item.

REQ_NEXT_ITEM

Move to the next item.

REQ_PREV_ITEM

Move to the previous item.

REQ_TOGGLE_ITEM

Select/deselect an item.

REQ_CLEAR_PATTERN

Clear the menu pattern buffer.

REQ_BACK_PATTERN

Delete the previous character from the pattern buffer.

REQ_NEXT_MATCH

Move to the next item matching the pattern match.

REQ_PREV_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 neither printable ASCII nor one of the above pre-defined menu requests, 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.

RETURN VALUE

menu_driver 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.

E_BAD_STATE

Routine was called from an initialization or termination function.

E_NOT_POSTED

The menu has not been posted.

E_UNKNOWN_COMMAND

The menu driver code saw an unknown request code.

E_NO_MATCH

Character failed to match.

E_REQUEST_DENIED

The menu driver could not process the request.

SEE ALSO

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

NOTES

The header file <menu.h> automatically includes the header files <curses.h>.

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.