Multiple UNIBUS on 750"s

[mike.rice%rand-relay at sri-unix.UUCP]

From:  Mike.Caplinger <mike.rice at rand-relay>

There is no 750 dual Unibus support in 4.1c; I don't know yet about
4.2.  As we have dual Unibus 750s at Rice, we were forced to write the
code ourselves for 4.1, and it should port easily to 4.1c anyway.
It's quite trivial, and if anyone is interested I can send them a
description of what needs to be changed, and maybe a diff, though I'll
have to get the Berkeley original back from tape.  I irresponsibly
deleted it locally in a fit of enthusiasm.