[SDL] Problem with WM_USER

[Albert Fernández Marsal]

Hi all,

I have to integrate a third party dll into my sdl application on a Win32 
platform. The dll polls for a resource and, to notify that something 
happended, it sends a WM_USER to a previously provided window handler. This 
handler cannot be the SDL window handler (I tried to, but it doesn't work). 
So, I created a window via CreateWindow API call. I have to run a PeekMessage 
loop over that window so it can process the messages, but it seems to conflict 
with the SDL_PollEvent loop that I run elsewhere.

The scenario is as follows (the calls are not sintactically correct, but they 
can be understood) :

Main thread (my app):
 while( true )
 {
  SDL_PollEvent( ev )
  if( ev.type >= SDL_USEREVENT )
   SDL_PushEvent( ev );
 }

Secondary thread (my app):
 hdl = CreateWindow('',0,0,0,0,0,0,0,0,0); // fake window
 Register3rdPartyDll( hdl );
 while( true )
 {
   // loop for processing the fake window event queue
  if( PeekMessage( hdl, WM_USER ) // only processing WM_USER event
  {
   translatemsg;
   dispatchmsg;
  }
 }
 
3rd party dll:
 register custom Window Proc for the fake window.
 Run a thread for polling the resource and post WM_USER to the fake window if 
smthg happened
 The custom window proc calls my code through a callback when WM_USER is 
processed.

The problem is that I get a Memory Exception inside the 3rd party dll in my 
main thread when I call the SDL_PollEvent.

Since the SDL_Event struct defines the event type as a UInt8 and WM_USER is 
0x0400 (out of range of a uint8 type), i cannot figure out how to bypass the 
WM_USER from inside the SDL_PollEvent loop.

Thank you very much for your help.

ALBERT