Comment by Joker_vD
6 hours ago
Okay, so basically something like Windows's "Anonymous Logon" SID, which doesn't belong to the Authenticated Users group: it's the group that's normally associated with the default Write permissions; the Users group has only read-only access.
That sort of idea, yes.
I've just done some research and it looks like the Debin Hurd people did attempt to actually implement this. I just never heard about it. There was a 'login shell' and a 'nouser'. The latter had am empty set of IDs, and this case (optionally) switched to an extra set of rwx permission bits that existed specifically for determining 'nouser' access.
* https://groups.google.com/g/linux.debian.ports.hurd/c/2rCbPl...