Ultrix tape job is unkillable!

[Guy Harris]

>Now (besides the obvious, cntl/C to the program), what do I
>do in the future when we have such a hung process?

Reboot.  I suspect the problem may be that an interrupt was lost, or
something like that, so the drive will appear to be *permanently* in a
non-usable state until you reboot, and the process blocked waiting for
the drive to finish whatever it was doing will block there forever;
since it's waiting at a priority less than PZERO, you can't get rid of
it with a signal.  Several different kinds of devices exhibit this
problem in various flavors of UNIX.

In this particular case, there is arguably a bug in the tape driver; I
don't know how easy it is to fix.