VMS shell under Unix (was: Re: why

[gillen at convexs.UUCP]

Maybe I should just say nothing but....

The VMS-like shell that you refer to is marketed as the "COVUEshell." I
think that the word COVUE stands for something like the "CONVEX-VAX User
Environment."  Anyway, it's a lot more than "shell scripts and aliases."
It's truly a shell that provides a subset of the commands and features
provided by DCL.

What's it got?  Well, it feels pretty much like DCL.  You can create and use
simple command procedures.  Many of the lexical functions were implemented.
There's an interface to the CONVEX UNIX Batch System so that the SUBMIT
and SHOW QUEUE commands work like VMS.  There are global symbols and
process-wide logical names.  There's even a MLisp file to make Emacs look
close to EDT.

What's missing?  Large, sophisticated command procedures will break.  No
local symbols, system-wide, or group-wide logical names.  Many of the
esoteric command switches are missing.  The concept of physical devices is
pretty weak (nearly nonexistant) but that's to be expected since it's
attempting to map VMS filename syntax to UNIX filename syntax.  Not all
of the DCL commands have been implemented.  Those that do exist enforce
an ordering of switches and arguments like any UNIX shell.

How does it work?  As I said above, COVUEshell isn't aliases and shell
scripts.  It's a shell that parses your DCL command and converts it to
the corresponding UNIX (Bourne shell) syntax.  A child is forked that
performs this command.  Pretty slick, actually.  For the system manager-
type that wants to wean users from VMS into the UNIX domain, there's a
Learn Mode that can be enabled that will display the equivalent UNIX
command that is going to be executed.

COVUEshell doesn't eat your machine alive, either.  It's surprisingly
supple.

I'm not trying to sell COVUEshell (or drum up business for CONVEX).
No, I'm not one of the developers of it, either.  I just use it daily
in the course of my development work at CONVEX.  I'm an old VMS hand 
who got tired of the cryptic UNIX commands.

Overall, if the goal is to give users familiar with VMS a "warm and fuzzy
feeling,"  COVUEshell does the trick.


					Dave Gillen





Credits and Disclaimers
The above opinion is mine and does not reflect the opinion of CONVEX.

DCL, EDT, VAX and VMS, are trademarks of Digital Equipment Corporation.

COVUE is a trademark of CONVEX Computer Corporation.

UNIX is a trademark of the AT&T Bell Laboratories.

"Gillen" isn't a trademark but I'm grateful to Mom and Dad for it.


I can't sing and I can't dance,
	guess I'll have to program for a living.