Levels of UNIX, an opinion, a question

[gwyn%brl-vld at sri-unix.UUCP]

From:      Doug Gwyn (VLD/VMB) <gwyn at brl-vld>

I don't think the shell is outside the kernel just because of address
space limitations; instead, that is a very good design and I have made
good use of it in the past by substituting other login shells for users
tailored to the applications (such as menu-driven interfaces for data
acquisition systems).