CHAA006%vaxb.rhbnc.ac.uk@CS.UCL.AC.UK (11/06/86)
We have had for some time, both at Bedford COllege and now at Royal Holloway and Bedford New College, a $ LOAD procedure, which precedes any/all requests for mounting. Each tape stored within our system is identified by a four-digit serial number, to which is prefixed a two-letter check code. The check code is pseudo-random, and known only to the user and the system. It does NOT appear physically on the tape. The LOAD command checks the VSN (check letters + digits, = Volume Serial Number), and only proceeds if correct. If used interactively, the user is asked if he or she wishes to wait for the drive, if it is found to be in use. If used in batch, waiting occurs automatically. Hope this may be of some help. ** Phil.