strings describing the drive status and error bits are so deficient
that the pointer is always NULL.
Reported by: Philippe Charnier <charnier@lirmm.fr>
but usually got confused with "eom". It didn't ring the warning bell
saying: "You are probably going to mark your whole tape as deleted
right now."
A warning message pointing to "weof" and "eom" is issued instead.
covered now, and i've attempted to give textual representations
instead of magic numbers.
The st(4) driver still misses some pieces; i'm going to implement the
EOM functionality RSN.
Any takers for the MTCOMP command? Seems to have never been implemented.