[Bug 52] PrgWin95: Problems with access to the root window

[Wine Bugs]

http://bugs.winehq.com/show_bug.cgi?id=52

------- Additional Comments From [e-mail]  2003-25-06 10:47 -------
Well, in sweeping this place, I decided to take another look at this bug..

Your last comment Francois says that you believe the fact that LockWindowUpdate 
is implemented only as a stub function is the cause of the problem..

In looking at msdn articles on this function, I have turned up this:

The LockWindowUpdate function disables or enables drawing in the specified 
window. Only one window can be locked at a time.

BOOL LockWindowUpdate(
  HWND hWndLock   // handle to window
);
Parameters
hWndLock 
[in] Specifies the window in which drawing will be disabled. If this parameter 
is NULL, drawing in the locked window is enabled. 
Return Values
If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero, indicating that an error 
occurred or another window was already locked.

Windows NT/2000/XP: To get extended error information, call GetLastError.

Remarks
If an application with a locked window (or any locked child windows) calls the 
GetDC, GetDCEx, or BeginPaint function, the called function returns a device 
context with a visible region that is empty. This will occur until the 
application unlocks the window by calling LockWindowUpdate, specifying a value 
of NULL for hWndLock.

If an application attempts to draw within a locked window, the system records 
the extent of the attempted operation in a bounding rectangle. When the window 
is unlocked, the system invalidates the area within this bounding rectangle, 
forcing an eventual WM_PAINT message to be sent to the previously locked window 
and its child windows. If no drawing has occurred while the window updates were 
locked, no area is invalidated.

LockWindowUpdate does not make the specified window invisible and does not 
clear the WS_VISIBLE style bit.

A locked window cannot be moved.

Requirements 
  Windows NT/2000/XP: Included in Windows NT 3.1 and later.
  Windows 95/98/Me: Included in Windows 95 and later.
  Header: Declared in Winuser.h; include Windows.h.
  Library: Use User32.lib.
--

Hopefully that is enough info for ya.  After reading it, I would have to agree 
with your last comment