Re: Passing C pointers through guile

[ludo@gnu.org (Ludovic Courtès)]

Hi,

"Kjetil S. Matheussen" <k.s.matheussen@notam02.no> writes:

> I haven't heard of the "uo" field before, but at least using a SMOB
> is really inconvenient, and using an unsigned long for storing
> pointers is really convenient. (BTW. How does swig and gwrap handle
> pointers?)

G-Wrap has "wrapped C types" (WCTs):

  http://www.nongnu.org/g-wrap/manual/Wrapping-a-C-Pointer-Type.html

IIRC, it uses a SMOB containing additional information behind the
scenes.

> I agree with Maciek that it would at least be mind-comforting to have
> functions like scm_to_ptr/etc, although not strictly necessary,
> since using integers works just fine.

`scm_{to,from}_uintptr ()' could be handy (patches welcome!).

That said, using a Scheme integer to represent a pointer wouldn't be
efficient (pointers would likely translate to bignums).

Thanks,
Ludovic.