Calling C from Common Lisp and vice versa

[Ilhamuddin Ahmed]

I am not sure if this has been asked before or not as I just joined this
newsgroup, and if it has I apologise.

I have an application in Common Lisp which consists of an array as a
data structure. I wish to pass this array to a C function which goes
through the array and display a graph in an X window. My problem is that
how would I call a C function from Common Lisp and how would I pass the
array (or any data structure for that matter) from Lisp to C.

The other side of the story is that, I have buttons in X (implemented in
C) which when clicked should change the state of the Common Lisp
program. So in this case, how can I execute a Common Lisp function from
C.

Any help would be very much appreciated. Thanks in advance.

						- Ilham.


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Ilhamuddin Ahmed, M.I.T. '91     | Arpa: ilham at juicy-juice.lcs.mit.edu
M.I.T. Lab for Computer Science  |       ilham at athena.mit.edu
Rm 213, 545 Technology Square,   |       ilham at eniac.seas.upenn.edu
Cambridge, Massachusetts 02139.  | UUCP: {backbone..}!mit-eddie!athena!ilham
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