> May there be other flags that we may need here in the future?
> Perhaps the second argument can be a bitmask to give us more options
> in the future:
> 
>       read_func(void *data, int *flags) {
>         read(buffer);
>         if (read was completed) {
>           *flags |= RB_NOGVL_SKIP_CHECK;
>         }
>       }
> 

Sorry for late response.
I agree with that. I commit your suggestion at r37681.

-- 
// SASADA Koichi at atdot dot net