VMS Rosetta stone for Unix admins?

[Gordon Morrison]

On this VMS FAQ:
http://saf.bio.caltech.edu/www/vms_beginners_faq.html
I read...
"What is OpenVMS, is it VMS?

First there was VMS, then Digital added POSIX, and renamed the
operating system OpenVMS. OpenVMS currently runs on both VAX and
AXP (ALPHA) CPUs."

...and...

"POSIX is a "standard" form of Unix. On OpenVMS, if you type POSIX you
will be transferred into the POSIX subsystem, which looks pretty much
like any other Unix you are used to. Or at least, it is no more different
from other Unixes than they are from each other."

I tried running posix, but no joy. I guess this means it just wasn't installed as an optional extra, but it can be installed without too much trouble? Is POSIX included in the standard OpenVMS distribution? We're running versions 6.2 and 7.1-2

[marsh_1]

hi,

there's a good thread on this here :-

http://forums13.itrc.hp.com/service/forums/questionanswer.do?admit=109447627+1246894604141+28353475&threadId=962048

hth

[Hoff]

OpenVMS V6.2 is from 1995; circa Windows 95 and c. RH2. V7.1-2 is from 1998; circa Windows 98 and c. RH5.

OpenVMS V8.3 (and V8.3-1H1 on Integrity) is the current OpenVMS release. That's from 2007 (and from 2007).

One of the larger areas of updates to OpenVMS over the last decade (and after the era of V7.1-2) has been around Unix compatibility; there were significant upgrades and additions to the C libraries and to the tools since that time.

In terms of the Unix shell products that have been available, first there was DEC/Shell. That was a V7-ish Bourne Shell.

Then came POSIX and the POSIX shell and the POSIX C APIs; that was around the time of the port from VAX over to Alpha. That was the core of the "Open" marketing of the era.

On OpenVMS V7.1 and later, you must use the POSIX V3.0 kit, which IIRC was the last POSIX kit. The POSIX product was retired at V7.2, again IIRC, and AFAIK it won't work on any recent releases. You'll need the 2.0 and 3.0 kits here.

Then gnv and bash arrived; this is the GNU-ish environment for OpenVMS, and the most recent shell and utilities port from HP.

AFAIK, OpenVMS doesn't (yet?) offer full Unix 03 compliance nor full C99 compliance.

One of the biggest issues here involves the continued use of ancient OpenVMS versions. Those are going to introduce various and sundry limitations, and in many dimensions. Now (again) don't map your Unix experiences and upgrades here, as user-mode code (that which is relatively free of latent bugs and using documented APIs) is expected to upgrade directly; no relinks required. You may (and usually will) need updated kernel-mode products installed. There are upward-compatibility statements around.

Moving applications from VAX to Alpha to Integrity is closer to a classic Unix upgrade (some Unix boxes do now have good binary upward-compatibility); you have to recompile and relink the code (and again, mapping how gcc works over will get you confused) and you may need to tweak some code that uses VAX (or Alpha) features.

[H.Becker]

>>>
I tried running posix, but no joy. I guess this means it just wasn't installed as an optional extra, but it can be installed without too much trouble? Is POSIX included in the standard OpenVMS distribution? We're running versions 6.2 and 7.1-2
<<<

VIP, VMS Integrated Posix, did not come with the OS, it was a separate kit on a separate CD, but free, or say: licensed with the OS. It would have been Posix 3.0, which was supported for 7.1 It should work on 7.1-2, but I'm not sure if that was officially supported. Anyway, support for VIP was discontinued in 1999. VIP was re-animated and hidden part of V7.2-6C2, which was the DII COE release of VMS. VIP somehow worked on 7.3 but it was never released in any form after COE. Later, the hooks in the OS for VIP support were removed. Given that history, I doubt you want to play with it, now.

You still would need to compile and install a Korn shell, but with a fully Posix compliant system as in V7.2-6C2 this was a piece of Black Forest Cherry Cake.