From: Jim Muller x3283
Subject: Lisp/C interface in Lucid
Date: 
Message-ID: <MULLER.91Jan25161923@vague.sarnoff.com>
Has anyone had any experience using the Lisp/C interface in Lucid (calling C
routines from Lisp)?  We were making use of it, but now I've tried to expand
that use, and it's not easy given the documentation.  Some things I'm having
trouble doing:

In a C routine, if I access a field in a structure, I have no trouble printing
  its value, but unless it is the 0th field in the structure, when I return
  it, the value which appears in Lisp is wrong.
If the structure consists of 2 fields and both are floats, no cross-language
  access seems to work: my lisp accessors can't return correct values from
  structures allocated in C with malloc; my c accessors can't return correct
  values from structures created with make-<def-foreign-struct>; and even if
  I use c accessors on malloced structures, while it can return their correct
  values, it can't print them out.

Thanks in advance for any help.

-- Jim