anchor.diff:  begin
     FSession := aSession;
     handle   := WinHttpConnect( FSession.Handle, PWideChar(aHostName), aPort, 0);
  +  if handle = nil then RaiseLastOSError;
     inherited Create( handle);
   end;
   
  
positive.code:                                      PWideChar(aReferrer),
                                       @accept,
                                       aFlags);
    inherited Create( handle);
  end;
  
  
negative.code:                          PWideChar(Pointer(aProxy)),        // may be nil
                           PWideChar(Pointer(aProxyBypass)),  // may be nil
                           aFlags);
    if handle = nil then RaiseLastOSError;
    inherited Create( handle);
  end;
  
  