vmchange script
I have a script to eject multiple tapes every week using vmchange. I dont have a root access on the master but I can run the command using pbrun
cat eject.sh
*
*
*
pbrun vmchange...
You could add a further line that runs a command to pipe out the used tapes and then use that in my script .... but in view of exactly what you want I think you should consider purchasing the Vault option that will do this for you.
