MENU_DRIVER(3) | Library Functions Manual | MENU_DRIVER(3)

# NAME

`menu_driver` — main menu handling function

# LIBRARY

Curses Menu Library (libmenu, -lmenu)

# 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>.

September 10, 1999 | NetBSD 11.0