This adds a new system callis similar to chroot(2), fchroot(2). The idea is to use itbut takes a file descriptor instead
with Capsicum for oblivious sandboxing, but for now it's justof path. A similar syscall exists in NetBSD. It is part of a larger
a chroot(2) that takes a fd instead of pathpatch to make absolute pathnames usable in Capsicum mode, but should
be useful in other contexts too.
This also modifies chroot(8) utility to add "-d", so one canSponsored by: DSbD
do eg "chroot -nd 5 /bin/bash 5< /compat/jammy".