16-bit apps starting and stopping notification

[Joshua Thielen]

Andreas Mohr wrote:

>On Sat, Apr 13, 2002 at 09:53:57AM -0400, Joshua Thielen wrote:
>
>>>Can somebody give me a hint how is better to approach
>>>implementation of 
>>>NFY_EXITTASK, NFY_STARTTASK events generation?
>>>
>>Does anyone know what ToolHelpHook does (KERNEL.341)? Could this be used by windows to hook a toolhelp notification function into
>>kernel.dll?
>>
>It installs notification handlers before important system events
>(dll load, task exit, ...).
>It returns the address of the previously installed notification handler,
>thus allowing for chaining handlers.
>It's basically a Win 3.1 replacement for RegisterPtrace().
>(same notification messages being used etc.)
>The notification msgs are NFY_xxx in toolhelp.h, BTW.
>
>It's all described in "Undocumented Windows".
>
OK., it looks like toolhelp.dll should install a callback function into 
the kernel using ToolHelpHook. Whenever a kernel event occurs, this 
callback function would call each function in the NotifyRegister 
function list corresponding to the kernel event.

But this presents a problem: How would you install a 32-bit wine 
callback function using ToolHelpHook16? I guess we could have separate 
ToolHelpHook32 and ToolHelpHook16 functions. I don't think it would be 
possible to chain the 32-bit and 16-bit functions together like they are 
in windows/hook.c. The kernel code would have to call the 16-bit and 
32-bit hooknotify functions separately.

Any better ideas? As I'm no wine pro, I hope I'm not spouting off 
meaningless nonsense here.

Josh