Long ago and far away, I was a kernel hacker for a mc68000-based UNIX
systems company. Our user address space began at 0x800000 for a variety of
reasons. This caused user programs that dereferenced a null pointer to die
of SIGSEGV. Often did I hear customers complain that our "hardware" was
defective because of this behavior. It was no fun telling them that they'd
made programming mistakes because it was not what they wanted to hear.

	sigh,

	Erik <fair@clock.org>