segmented memory models

[Paul Koning]

>>>>> "Fred" == Fred Cisin <cisin at xenosoft.com> writes:

 >> > address 0 be NULL was not around on the micros, and putting it
 >> at the
 Fred> On Mon, 4 Aug 2008, Tony Duell wrote:
 >> I wasn't aware that this was a requirement of C, or any other
 >> language.

 Fred> C actually insists that address 0 is an invalid address!

Pedantically: not quite.  It says that 0 is the token representing a
null address.  It doesn't say that the encoding of such a pointer is
the same as that of the integer 0.

In practice that's probably the case in all platforms -- certainly all
current ones.  I'm not 100% sure about the PDP-10, never mind the
Cyber 6600... both of which have oddball pointers.

      paul