The SHOW DRIVE command shows the status of drives. One of these
    possible states is reported:

    o  Full or <barcode> -- The drive contains a cartridge. The bar code
       value of the cartridge occupying the drive appears if the media
       robot is capable of reading cartridge bar codes.

    o  Empty -- The drive contains no cartridge, and is available for
       use.

    o  Unavailable -- The drive is unavailable for use.

    Format

    SHOW [ROBOT robot_name] DRIVE [[[drv_number]|[drv_number-drv_number]],...]