[cffi-devel] Re: cffi/allegro crash

[Surendra Singhi]

Luís Oliveira <luismbo at gmail.com> writes:

> On 2005-dec-18, at 13:25, Surendra Singhi wrote:
>> Is there any uniform way of passing C null value to functions?
>> Should I pass `0'?
>
> Glad you were able to fix this issue! You should pass (cffi:null-
> pointer). CLISP does convert NIL to the null pointer which is
> unfortunate for this reason (Hi
> Joerg!) :-) And it seems Lispworks does too.
>
> The lack of uniformity is very unfortunate here. This needs to be
> fixed. We should either a) translate nil->null everywhere, b) don't
> translate nil->null anywhere or c) offer the two alternatives through
> two different types.
>
It will be interesting to know what other lisp implementations like CMUCL,
SBCL do? I will vote for clisp's and lispworks approach, it seems least
surprising to me.

Another related issue is when a C function returns a null pointer. The
behavior in that case should be also uniform.

Thanks.
-- 
Surendra Singhi
http://www.public.asu.edu/~sksinghi/index.html

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