Well, I hope this reply is not too late.

Actually "dependent on specific/different Scheme implementation" just
indicates that I *really don't know* why  corresponding srfis are
unnamed. Despite my efforts to read all SRFI, most of the time I find it
difficult to determine whether an unnamed SRFI can have a name. As you
mentioned in the example, if SRFI-111 is portable in a scheme
implementation following the R6RS standard, then I believe it should
have a name.

As for the second point you mentioned, I think I need more comments.

在 6/14/25 04:15, Shiro Kawai 写道:
> Number of srfis are omitted because of "dependent on
> specific/different Scheme implementation" but what exactly does that
> mean?
>
> For example, srfi-111 can be portably implemented on any
> R[67]RS-compliant implementation.  Does the fact that some
> implementation provides them natively has something to do with this
> classification?
>
> Also, some srfi does need non-portable support to implement (e.g.
> access to hardware timer) but the interface is portable nonetheless,
> and it seems useful to have a standard name for them as well.
>
>