Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!ucbvax!HDETUD1.TUDELFT.NL!RCOPROB
From: RCOPROB@HDETUD1.TUDELFT.NL (Rob van Hoboken)
Newsgroups: comp.lang.asm370
Subject: deep down in CP ...
Message-ID: <9002061526.AA05942@lilac.berkeley.edu>
Date: 6 Feb 90 14:40:50 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Reply-To: IBM 370 Assembly Programming Discussion List <ASM370%UCF1VM.bitnet@lilac.berkeley.edu>
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I've got two rather difficult question, which of course I couldn't find in
the proper docs.  Both involve both /370 as well as XA systems.  Replies
from both sides would be appreciated.

1. incore directory
I would like to obtain data about all users defined in the directory, without
having to read the source or object directory from DASD.  Data I am after are
mostly MDISK definitions (vaddr, start, size, volume).  Is there any way to
get to the incore version of UDIRECT blocks (get CP to page in these blocks
for me, and return a pointer to me) ?

2. doing I/O to ALL DASD
How would CP react if I take one of my VDEVBLOKs, and change the RDEVBLOK
pointer and extent descriptors, i.e. make an MDISK vaddr of my machine a
full pack minidisk on just any real device ?
Of course I 'only' want to read :-)
I guess CP wouldn't mind if I overlay a not owned disk with a full pack, and
even a system owned shouldn't give a hoot.  How about disks that are already
ATTACHed to some (MVS) guest ?  How would CP (and MVS) feel about my doing
some I/O on their DEEDICATEd disks ?

I would like to issue SENSE comamnds to ALL disks in the farm and READ the
ALLOCATION MAP from all OWNED disks.  How about it, has any of tried this
before ?  How did it work out, or why could it not work ?