On Fri, Apr 06, 2001 at 10:23:21AM +0200, Thomas Michael Wanka wrote:
> currently only OS/390 (BS2000 or whatever) will run as native OS, 
> unixes will run in logical partitions. I think the ix (a german computer 

IBM mainframes used to either run an OS or run the VM os hosting one or
more guest OS systems. Important parts of VM are now in the microcode
of current systems enabling the partitioning of systems. From the guest
OS's POV the partitioning isn't a factor, ie any OS that can run bare
metal can run in a partition. The partitions are called LPARs. (Mainframers
LOVE cryptic combinations of letters.)

The number of LPARs is limited, perhaps as low as 16 max. More than that
requires VM (for virtual machines). Of course, you are more than free to
run with multiple LPARs running VM with a number of guest systems.....

OS's that run bare metal, in an LPAR, or under VM are:

*) OS/390 or z/OS (z/OS is the new name of OS/390 which was MVS. z/OS has
   support for 64-bit real addressing, even though 64-bitness isn't
   available to programs yet). 

   The last release of MVS that was free was 3.something or 4.something,
   check the Hercules web site for details. http://www.hercules.cx/ I
   think.

*) VM or z/VM (and VM normally hosts the CMS operating system, which is
   a single-user operating system run as a guest when people log on.)

*) VSE or z/VSE

*) Linux/390

I don't know what happened to AIX/370. I would bet it is very dead.
IBM mainframers suck rocks at Unix. Bad. They now have "OpenEdition"/
"UNIX System Services"/"UNIX/390" on OS/390 and WOW does it suck.
Picture a bunch of non-Unix people trying to reimplement Unix from
scratch with just standards documents to guide them. Also, picture
these people with mainframe mindsets about things like how features
get added to a system.

(The rest of my post is me venting steam about how much USS sucks.
Feel free to ignore it.)

USS (with the release of V2R10 last year) finally gained /bin/csh. No
joke. They have /bin/ksh as a symlink to /bin/sh, and their docs talk
about "The UNIX System Services Shell". They don't ship telnet or
rlogin or rsh (after all, after telnetting to a mainframe why would
you want to telnet out again?). They ship sendmail but it doesn't
work due to a butchering of the distribution (you know all those example
M4 files? Gone.). They don't ship m4 despite it being needed to configure
sendmail. X? Forget about it. The resize command? Deal without it.

They ship an alternative to sendmail which is normally run outside
of USS (ie, in vanilla MVS). It's name? "SMTP" (Stupid name designed
to generate confusion I think.)

You can get super-fancy programs like "telnet" or "xterm" from the
"Tools and Toys" web page. Sheesh, and I thought compiling gtar and
gzip on SunOS 4.1.1 was irritating enough....

They don't support Hesiod or NIS. You want NIS? File a "requirement"
through official channels. If you want USS to have feature parity with
where Unix was 20 years ago then you need to file lots of paperwork and
go out and gather up support among the user population. IBM isn't going
to do it for you.

Did I mention that mainframe people suck at Unix? Linux/390 is a blessing
(but I would prefer NetBSD/390 myself). I swear I'd rather use plain
MVS things like TSO, ISPF, or JCL over USS simply because TSO, ISPF,
and JCL don't claim to be Unix.
-- 
Kevin P. Neal                                http://www.pobox.com/~kpn/

"Nonbelievers found it difficult to defend their position in \ 
    the presense of a working computer." -- a DEC Jensen paper