oWin:SysCommand( <nWParam>, <nLParam> ) -> <NIL>

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 PARAMETER:

  <nWParam>    This parameter specifies the type of system command requested.
               This parameter can be one of the following values: 

                SC_CLOSE      Close the window. 

                SC_HOTKEY     Activate the window associated with the ap-
                              plication-specified hot key. The low-order word
                              of <nLParam> identifies the window to activate

                SC_HSCROLL    Scroll horizontally. 

                SC_KEYMENU    Retrieve a menu through a keystroke. 

                SC_MAXIMIZE   Maximize the window. 

                SC_MINIMIZE   Minimize the window. 

                SC_MOUSEMENU  a menu through a mouse click. 

                SC_MOVE       Move the window. 

                SC_NEXTWINDOW Move to the next window. 

                SC_PREVWINDOW Move to the previous window. 

                SC_RESTORE    Restore window to normal position and size. 

                SC_SCREENSAVE Execute the screen-saver application specified 
                              in the [boot] section of the SYSTEM.INI file. 

                SC_SIZE       Size the window. 

                SC_TASKLIST   Execute or activate the Windows Task Manager 
                              application. 

                SC_VSCROLL    Scroll vertically. 


  <nLParam>    the low order word conatains the horizontal position of cursor,
               the high order contains the vertical position of cursor


 DESCRIPTION:

  This method is invoked by a WM_SYSCOMMAND message, which is sent when 
  the user selects a command from the System menu (sometimes referred to as 
  the Control menu) or when the user selects the Maximize or Minimize button.

  ::SysCommand() handles the SC_CLOSE messages and delegates all
  other mesages to ::oSysMenu