C Interface example

[artifact.one@googlemail.com]

Hi.

I'm having a bit of trouble getting my head around calling C code
in Ada. I'll spare you my failed attempts, basically I have this code:

(vector.h)

#ifndef VECTOR_H
#define VECTOR_H

float *vec_addNf(float *, float *, unsigned int);

#endif

(vec_add.c)

#include "vector.h"

float *vec_add(float *va, float *vb, unsigned int ne)
{
  unsigned int ind;
  for (ind = 0; ind < ne; ++ind)
    va[ind] += vb[ind];
  return va;
}

Now what would be the most simple and portable way to write
a vector,ads and vector.adb file? (Specification and body, in case
those are compiler-specific filenames, I'm not intimate with the
Ada language spec yet!). I just don't have a good enough
understanding of the language to see how it all fits together
yet and I usually learn by example.

MC