Out of range pointers

[Doug Gwyn]

In article <33547 at XAIT.XEROX.COM> g-rh at XAIT.Xerox.COM (Richard Harter) writes:
>However it would be very nice if there were a library routine that would
>tell you whether a pointer was legal or not.

I think if your code has to worry about this, it is ALREADY in trouble.
Pointers should come in two flavors: null (which is easy to test) and
valid (which you should be able to assume when non-null).