From: Julian Elischer <julian@jules.DIALix.oz.au>

Subject: Re: Error reading from DAT (fwd)
Date: Mon, 11 Oct 1993 03:02:39 -40962758 (WST)

Some tapes won't do anything until you tell them to load.
Other tapes think that being asked to load is a great excuse to
make the next command return a "unit attention" (media changed) error.
Since we need to do the load, throw in a dummy instruction to cop the
error.

specifically for DEC DAT drives.