' zunächst die benötigten API-Deklarationen
Private Declare Function SendMessage Lib "user32" _
  Alias "SendMessageA" (ByVal hwnd As Long, _
  ByVal wMsg As Long, ByVal wParam As Long, _
  ByVal lParam As Any) As Long
 
Const WM_SYSCOMMAND = &H112
Const SC_CLOSE = &HF060
Const LNULL = 0&
 
a = SendMessage(CurHwnd, WM_SYSCOMMAND, SC_CLOSE, LNULL)