[Info-vax] Whither VMS?

[Rich Alderson]

koehler at eisner.nospam.encompasserve.org (Bob Koehler) writes:

> In article <mdd7hvqa5c2.fsf at panix5.panix.com>, Rich Alderson
> <news at alderson.users.panix.com> writes:

>> I'm quite sure.  Tops-10 and TOPS-20 shared no code whatsoever.

>    That's interesting.  Having used TOPS-10 and TOPS-20 I knew the
>    user interface and OS calls were both quite different, but I did
>    not know TOPS-20 was based on TENEX.  The TOPS-10 command interpeter
>    was certainly much less verbose than the TOPS-20 EXEC.

The Tops-10 command interpreter was part of the monitor ("kernel" for those
from a later time).  The TOPS-20 command interpreter was a user-mode program
called EXEC.EXE, and actually *can* be replaced by another user-mode program.

(Login directories have a "Must-Run-Program" attribute, with associated name
of the program to be run.  We experimented with our port of bash on the XKL
Toad-1.  It pretty much worked.)

>    I wonder how hard it was supporting all the TOPS-10 UUOs in TOPS-20
>    without a common base.

Not all the Tops-10 UUOs were supported.  The TOPS-20 code for that was frozen
in the Tops-10 5.03/6.01 time frame.  6.01 introduced Tops-10 to the KL-10.

>    Are you saying TOPS-10 was not a demand paged system?

Only very very late in its history.  I think that 7.03 was the first such
release; 7.04 certainly uses the TOPS-20 memory model.  In fact, a KL-10
is loaded with the same microcode for TOPS-20 v7.0 or Tops-10 v7.04.  Those
were released in the spring of 1989.  (I chaired the DECUS announcement
sessions in Cincinnati.)

-- 
Rich Alderson                  "You get what anybody gets. You get a lifetime."
news at alderson.users.panix.com                           --Death, of the Endless