On Thu, 13 Apr 1995 17:50:05 GMT Mark Ranft said:
>In article <cm.797523270@merle>, [log in to unmask] says...
>>I have two remote sites where we've set up backups to run as jobs
><snip>>
>>Is there any way to test for the presence of a tape (scsi dat)
>mounted from a job stream?
 
>Try this Command file:
 
[...major snip of another showdev command file...]
 
OK, this is at least the 3rd suggestion along the same thread of :showdev.
Well, I hate to rain on your parade, but if you mount a tape on a drive it
will indeed AVR and give the Volume (unlabelled) mounted on... message, and
yes, showdev will show it with a mounted tape.  We all know this part...
 
But if for whatever reason someone manually unloads the tape, the showdev
output remains consistent with the last known state of the drive.  The AVR
process responds to mounts, but it does not respond to dismounts.
 
I know it is unlikely, but it is a fact of life to consider that it may
happen.  Disc (disk?  Is there a consensus now that we're Posix-aware?)
mounts/availability are detected by AVR as well as dismounts (or VSOPEN and
VSCLOSE).  But for tapes, the system is unaware that a tape was dismounted.
 
[\] Jeff Kell, [log in to unmask]