grpc_invoke_arg_stack_np - Executes an RPC.
  int grpc_invoke_arg_stack_np(grpc_object_handle_t_np *handle,
                               char *method_name,
                               grpc_arg_stack_t *stack)
  grpc_object_handle_t_np *handle  char *method_name  grpc_arg_stack_t *stackThe grpc_invoke_arg_stack_np() function calls the method defined by the object handle. The grpc_invoke_arg_stack_np() function is blocked until the execution of the called method is completed.
This function is MT-safe.
If successful, 0 is returned. In the case of an error, -1 is returned.
  GRPC_NOT_INITIALIZED  GRPC_OTHER_ERROR_CODE