NULL vs 0 - chapter and verse

[Mike Tilson]

Pointer subtraction on a 16/32 bit implementation does not break the
standard; it is simply an implementation restriction.  The subtraction
of two 32 bit pointers may well yield a 16 bit int -- so what?  In
practice, that means that under such an implementation it is unreasonable
to have single storage objects with more than 16 bit's worth of elements.
That is a restriction, not a logical inconsistency.

/Mike Tilson	decvax!hcr!hcrvax!mike