TrackPopupMenu

[Faiseur]

Excuse my bad English (translate)

I do not know if it is the good topic, i want only to announce a bug under Windows 2000 sp4 (Windows XP ok) by using example "RCLKMENU" of the pack Masm32.  By using the right button of the mouse the program "RCLKMENU" stops (error) when the menu appears.  That relates to the function "TrackPopupMenu", here: 

Code Select Expand


   .ELSEIF uMsg==WM_CONTEXTMENU   ;has user right clicked mouse?
      mov eax, lParam             ;if so, show the popup menu
      and eax, 0ffffh
      mov ebx, lParam
      shr ebx, 16
      invoke TrackPopupMenu, mnuhWnd, TPM_LEFTALIGN, eax, ebx, 0, hWnd, 0


I did not understand well, but by replacing "ebx" by "ecx" that functions without bug. 

Code Select Expand


   .ELSEIF uMsg==WM_CONTEXTMENU   ;has user right clicked mouse?
      mov eax, lParam             ;if so, show the popup menu
      and eax, 0ffffh
      mov ecx, lParam
      shr ecx, 16
      invoke TrackPopupMenu, mnuhWnd, TPM_LEFTALIGN, eax, ecx, 0, hWnd, 0



thank you for your good work

[Relvinian]

hehe, this probably should be under the MASM forum since it relates to one of the examples in the MASM32 package.

But you are correct, the example is using the EBX register without preserving it first.

Relvinian

PS - For those maintaining the examples, the file is:
\masm32\examples\examples8\rclkmenu.asm