🚀 go-pugleaf

Trying to use the 'own filtering' function of WinXP, I get two
problems

The main snippet was

  OPENFILENAME ofn;
  memset(&ofn, 0, sizeof(ofn));
  ofn.lStructSize=sizeof(OPENFILENAME);
  char filename[_MAX_PATH]=""/*init filename*/;
  ofn.lpstrFile=filename; // this is a must
  ofn.nMaxFile=sizeof(filename);
  ofn.Flags=OFN_ENABLEHOOK|OFN_EXPLORER|OFN_ENABLEINCLUDENOTIFY;
  ofn.lpfnHook=(LPOFNHOOKPROC)OFNHookProc; 
  if(GetOpenFileName(&ofn)==FALSE) {
    ...
  }


which OFN_ENABLEINCLUDENOTIFY flag calls (on XP) the OFNHookProc
procedure with the expectation it handles 


UINT APIENTRY OFNHookProc(
    HWND hdlg,	// handle to child dialog window
    UINT uiMsg,	// message identifier
    WPARAM wParam,	// message parameter
    LPARAM lParam 	// message parameter
   ) {

  switch(uiMsg) {
    case WM_NOTIFY: {
      LPOFNOTIFYEX lpon = (LPOFNOTIFYEX)lParam;
      if(lpon->hdr.code==CDN_INCLUDEITEM) {
        return(ShouldBeIncluded(lpon));  // BREAKPOINT
      }
  }
  return(0); // default handler processes message
}

Doing a breakpoint at the BREAKPOINT-position of  OFNHookProc()
the debugger really stops for each file in the directory.

1)
Unfortunately I did not come any further, i.e. I had no success
evaluating lpon such, that I get the filename. Perhaps someone knows
how to extract it from LPOFNOTIFYEX.

2)
Creating a function ShouldBeIncluded(), which always returns false
  bool ShouldBeIncluded(LPOFNOTIFYEX lpon)) {
    return(false);
  }
strangely results in a open-file-box which also displays all the
files. (Same result as if ShouldBeIncluded() always returns true.) I
found a interness-information that this self-filtering will only work
for non-system-directories, but the directory I run through is
something like o:\demo and such definitively no such dir.

Any ideas?

Thanks a lot,

Michael