Comments on: Getting started with CFFI

By: Space Station Lambda » Laying logging foundations

Space Station Lambda » Laying logging foundations — Wed, 30 Jan 2008 11:44:20 +0000

[...] one for the load averages, so we can see whether an error might have occurred due to heavy load (maybe a race condition): [...]

By: Leslie

Leslie — Fri, 25 Jan 2008 09:51:54 +0000

baleog, I recommend ffa for arrays with more than one dimension. If you don't want to use it, you need to keep track of N pointers, where N is your array's dimension. I don't think you can use Lisp arrays with CFFI (or UFFI, for that matter).

By: Ramarren

Ramarren — Thu, 24 Jan 2008 21:54:18 +0000

When dealing with arrays something like http://www.cliki.net/ffa is helpful, I think.

Mikael, how exactly do you imagine dynamic loading of static libraries would work? I suppose you can use Embeddable Common-Lisp from http://ecls.sourceforge.net/ which generates C code, so one can link it with anything C compiler can.

By: Mikael Jansson

Mikael Jansson — Thu, 24 Jan 2008 20:33:50 +0000

Thanks for the snippet! It was precisely was I was looking for. I’m just beginning my Lisp journey, and right now I’m thinking about working on a project that requires access to C bindings.

Is there an equivalent for static (.a) libraries?

By: baleog

baleog — Thu, 24 Jan 2008 15:52:38 +0000

and what do i need to define if i want to call c-function with multi-dimensional lisp array?

something like this:

;;int some_c_function(double *, int dim1, int dim2);
(let ((ar (make-array (list *dim1* *dim2*) :element-type ‘double-float)))
(some-c-function ar *dim1* *dim2*))