Date   : Tue, 17 Jan 1984 00:10:00 EST
From   : Jerry E. Pournelle <POURNE@mit-mc>
Subject: Function 37

It is not required that you RESET the system if the BIOS is
properly written, but you will have to do a ^c warm boot if you
have changed disks; R/O actually means that the bit map doesn't
match t he current directory entries.
       As to BIOS detecting door opening, on 5 1/4" disks there
is no hardware detect is there?  Nor do I know a way to detect
whether a door HAS BEEN OPENED although you can have (and my
BIOS does) a look at the door to see if it is open NOW and put
up a message like "Load Drive A" or "Please close Door" or some
such; I recall startling some Morrow and Compupro troops a
couple of years ago by inviting them over to the house and
showing them I could access non-existent disks, open doors, or
anything else, and recover from it.
       But that was before fn 37, which can have unrecoverable
errors.