Re: FFI again

[Stefan Monnier <monnier@iro.umontreal.ca>]

> The author of the sxemacs libffi interface offered to provide it for
> emacs some time ago on this list, as I recall.
> If that doesnt pan out I dont think writing an emacs libffi interface
> from scratch is too hard.

I don't remember it being mentioned.  I do vaguely remember someone
(Lars, maybe) mentioning that it can be a lot easier to write C code
that massages the lib calls to make them into subrs (as is done for
gnutls and libxml) than it is to write code for something like an FFI.

I personally don't have any experience either way.  But I think that
a good benchmark for an FFI is to make our libxml and libgnutls
code use it.

> I really don't like this idea.  You either force users to have the Emacs
> headers, Emacs import library, and a C compiler available to install a
> package or you provide pre-compiled binaries for popular platforms and
> create an ABI versioning nightmare.

The plan would be to require headers and a C compiler.
Precompiled libraries could be considered for the Windows platform, but
only if we can keep the versioning nightmare in check.

> The routines declared in lisp.h do not form stable interface.

Indeed, we'd need to define a slightly more stable API.


        Stefan