XENIX 1.3 and usr/spool - (nf)

[Guy Harris]

Actually, the chroot kludge (which isn't present in vanilla V7, but is in
both Berkeley and USG releases of UNIX) plugs a security hole.  "." and ".."
have been getting more special over time; they are *very* special in 4.2BSD,
as the "mkdir" and "rmdir" system calls have to know about them, and the
"rename" system call, which allows you to rename directories and is not
privileged, treats them specially as well.

	Guy Harris
	{seismo,ihnp4,allegra}!rlgvax!guy