9 Aug
2015
9 Aug
'15
3:03 p.m.
No, the OS did the drive assignments, and then prompted the operator to
do the mount of the appropriate VolSer on a given drive. The label was
of course checked as part of the OS/360 open process, and if there was a
label, and it was not expired, one could not write over it, or, whether
reading or writing, that the label matched the requested DSN.
(Remember that OS/360 never heard of the 3480 tapes and their
autoloaders - things presumably changed then, along with tape library
management software, but by then I had moved on from mainframes, and
what little I did with them didn't involve tape).
The operators I worked with almost never mismounted a tape.
JRJ
On 8/9/2015 1:13 PM, Chuck Guzis wrote:
On 08/09/2015 10:45 AM, Jay Jaeger wrote:
Seems dangerous to me: duplicate data set names
on different tapes would
confuse it (plus, if the DSN is long, the entire DSN does not actually
appear in the tape label). I worked with OS/360 and MVS in my career
and we never did anything like that with it.
So you'd trust your job to a 9-5 operator who really didn't care what
the machine was doing to make tape assignments?
Wow. Good thing that tapes have write-enable rings.
--Chuck