Re: [Gcl-devel] gcl/acl2

[Peter Wood]

Hi

On Fri, Nov 01, 2002 at 07:58:13PM -0500, Camm Maguire wrote:

> What I don't understand is how foreign libraries are to be supported
> in lisp *distributions*.  Does one ship an image with every available
> interface compiled in, and thereby requiring the requisite libraries
> in order to run?  This seems like a quite odd model, given the large
> size of lisp images and the perspective of the system as a compiler.
> What if gcc required libblas to run?  Or does one have a large variety
> of images, gcl/blas, gcl/blas/lapack, gcl/mpi, gcl/blas/mpi, each ~ 10
> Meg?
> 

Its only a problem if you have to ship an image.  If you can
distribute the source code then its easy.

CLISP does it at compile time.  If you want suppport for Glibc, on a
Gnu/Linux system, you can specify it as an option at configure time.
Ditto for the xlib (clx) support and postgres.

This approach is (somewhat) facilitated by a module system. However
GCL could also do this, probably quite easily without modules.  So the
user could say ./configure --with-blas, and configure would add the
necessary declarations, blas.c and blas.lsp files to the build
process.

As an aside: 

CLISP's FFI's big drawback is that whatever you want has to be
compiled in.  You can't load foreign bindings "on the run". (Joerg
Hoehle has written a dynamic extension to the CLISP FFI, but it
doesn't appear to be in CLISP yet.)  It is very easy to do this in
GCL, with dlopen, but a better approach would be to load and link (if
that's possible).

Regards,
Peter