Summary

    The TrackPopupMenu() API in the Windows 3.1 SDK know documents
and uses the last parameter.  The final parameter is now documented
as a LPRECT that describes the rectangle that the menu will accept
the button up without dismissing the menu.  This is useful for
applications that bring up a popup menu in response to a WM_LBUTTONDOWN.
The user then longer has the responsibility of holding the mouse button
down until a menu selection is made.  The button can be released and the
menu choice can then be chosen with the next button click.  This command
could be used to bring up a popup menu associated with an icon, or some
other graphical object.  The last parameter of TrackPopupMenu(), does 
not have this effect in Windows 3.0.



