function DetectBT: PChar; stdcall;
var
  xReg: TRegistry;
  sTemp: string;
  P: PChar;

begin
  sTemp := '';
  xReg := TRegistry.Create;
  if xReg.KeyExists('bittorrent\shell\open\command') then begin
    xReg.OpenKey('bittorrent\shell\open\command', False);
    if xReg.ReadString('') <> '' then begin
      sTemp := xReg.ReadString('');
      sTemp := Copy(sTemp, 2, Length(sTemp) - 1);
      sTemp := Copy(sTemp, 1, Pos('"', sTemp) - 1);
      P := PChar(sTemp);
      sTemp := ExtractFileName(sTemp);
      if (LowerCase(sTemp) = 'btdownloadgui.exe') then
        Result := PChar('1|' + P)
      else
        Result := '2|?';
    end
    else
      Result := '2|?';
  end
  else
    Result := '2|?';
  xReg.CloseKey;
  FreeAndNil(xReg);
end;