%typemap(in) void (* cb)(void *) , void *data , void (cb)(void *){
  //if SvGETMAGIC($input) {}; 
  $1 = INT2PTR($1_ltype, SvUV($input));
  printf(":: x%" UVxf " to x%lx\n", SvUV($input), $1);

  {
    int ret = SWIG_ConvertFunctionPtr($input, (void**)(& $1), 0);
    printf(":: to x%lx\n", $1);
  }

  if(SvGMAGICAL($input)) mg_get($input);
  $1 =  DPTR2FPTR($1_ltype, SvUV($input));
  printf("::DPTR2FPTR x%lx to x%lx\n", SvIV($input), $1);
}