grpc_function_handle_init_with_attr_np -  Initializes a function handle.
  grpc_error_t grpc_function_handle_init_with_attr_np(
                   grpc_function_handle_t *handle,
                   grpc_handle_attr_t_np *attr)
  grpc_function_handle_t *handle  grpc_handle_attr_t_np *attrThe grpc_function_handle_init_with_attr_np() function initializes a function handle.
This function is MT-safe.
If successful, GRPC_NO_ERROR is returned. In the case of an error, Error code is returned.
  GRPC_NOT_INITIALIZED  GRPC_SERVER_NOT_FOUND  GRPC_FUNCTION_NOT_FOUND  GRPC_RPC_REFUSED  GRPC_OTHER_ERROR_CODE