[Info-vax] Orphaned processes on OpenVMS

[Johnny Billquist]

On 2011-05-26 13.36, Rob Brown wrote:
> On Thu, 26 May 2011 at 11:50 -0700, Johnny Billquist wrote:
>
>> On 2011-05-26 11.43, Rob Brown wrote:
>>>
>>> In VMS, as Bob says, you must initialize before you can mount.
>>
>> Interesting. So you (or anyone) is allowed to do I/O to an unmounted
>> disk?
>
> Who prevents it in M-Plus? I can't remember when or if I last tried
> this. Can I not, as a privileged or as a non-privileged user, do
> disk-driver QIOs to an unmounted disk? Somebody must be able to,
> otherwise how would MOUNT work?

No, no I/O is allowed to an unmounted disk in M+. This is controlled by 
the QIO directive processing itself.
Check around line 480 (label 46$) and forward in LB:[11,10]DRQIO.MAC

Mount is not doing only doing I/O. In order for any I/O operation (with 
a few exceptions) to be allowed, the volume valid bit must be set.
Mount starts by setting the volume valid, before it do any I/O, and then 
resets it again, in case the mount wasn't good.

>> That would (to me) seem like a weird thing. So when is there ever a
>> point for foreign mounted disks in VMS?
>
> Tradition? Looks like RMS needs the disk to be mounted. I wonder if RMS
> is used for device-mode I/O as well as for file I/O.

Well, RMS cannot play with foreign disks, or...?

> $ ld connect deleteme.dsk
> %LD-I-UNIT, Allocated device is OMEGA$LDA2:
> $ dump/block=count=1 lda2: !LDA2 is not mounted
> %DUMP-E-OPENIN, error opening LDA2:[BROWN.TEMP].; as input
> -RMS-E-DNR, device not ready, not mounted, or unavailable
> $ mount lda2 test
> %MOUNT-I-MOUNTED, TEST mounted on _OMEGA$LDA2:
> $ dump/block=count=1 lda2: !LDA2 is mounted files-11
> %DUMP-E-READERR, error reading LDA2:
> -SYSTEM-F-NOPRIV, insufficient privilege or object protection violation
> $ dismount lda2:
> $ mount lda2 test/for
> %MOUNT-I-MOUNTED, TEST mounted on _OMEGA$LDA2:
> $ dump/block=count=1 lda2: !LDA2 is mounted foreign
>
> Dump of device LDA2: on 26-MAY-2011 14:25:21.84
>
> Logical block number 0 (00000000), 512 (0200) bytes
>
> 03039401 001E65C0 11C00200 15C600A0 ......e...... 000000
> ...

Hmm. Ok. So it does not actually allow I/O to unmounted volumes. So, is 
disk file struction initialization special, in order to allow that I/O?

	Johnny