grpc_object_handle_get_attr_np - Gets handle attributes.
  grpc_error_t grpc_object_handle_get_attr_np(
                   grpc_object_handle_t_np *handle,
                   grpc_handle_attr_t_np *attr)
  grpc_object_handle_t_np *handle grpc_handle_attr_t_np *attr This function is MT-safe.
  GRPC_NOT_INITIALIZED  GRPC_INVALID_OBJECT_HANDLE_NP  GRPC_OTHER_ERROR_CODE