dynamic array parameters

[Wayne Throop]

To reference an element of a variably sized multi-dimensional array,
David Tribble recommends

>  (*(a + i*d1 + j))    /* same as a[i][j]	*/

along with using macros to simplify, like so:

> #define index(a,i,j)  (*(a + i*d1 + j))
>  index(a, i, j)       /* same as a[i][j]	*/

Good idea.  I'd just like to note that, using pointer/array equivalence,
the somewhat complicated expression can be written a little less
confusingly, as

        a[i*d1 + j]

It might still be advisable to use the macro, but then again, maybe not.
The more-than-two-dimensional cases are still pretty confusing:

        a[(i*d1 + j)*d2 + k]

Also, I'd recommend declaring the formal "a" as "int a[]" rather than
"int *a", unless it is important for some reason to treat "a" as an
lvalue.
-- 
Wayne Throop at Data General, RTP, NC
<the-known-world>!mcnc!rti-sel!dg_rtp!throopw