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From: urlichs@smurf.sub.org (Matthias Urlichs)
Newsgroups: comp.periphs.scsi
Subject: Re: Ques: how to indicate medium removed
Message-ID: <1crff2.501@smurf.sub.org>
Date: 13 Sep 90 19:04:09 GMT
References: <1990Sep11.191040.24715@Matrix.COM>
Organization: University of Karlsruhe, FRG
Lines: 22

In comp.periphs.scsi, article <1990Sep11.191040.24715@Matrix.COM>,
  srm@matrx.matrix.com (Steve Morris) writes:
< 
< How does a SCSI drive (Syquest) indicate that the (removable) medium
< is not currently present? Is there something more descriptive than
< receiving the UNIT ATTENTION sense key from a REQUEST SENSE command?
< 
Yes -- if the drive is stopped, you'll get a UNIT NOT READY.
Presumably, trying to start the drive would indicate whether a medium is
present. ;-)
(The sense data might also show this, but I didn't test it.)

Unit Attention should only show up when the drive is up again.

It might make sense to prevent the user from removing the medium if a volume
is mounted on it / if the device is opened.
Assuming, of course, that you have an OS whose drivers can find out such
things. (MacOS or Unix drivers can.)

-- 
Matthias Urlichs -- urlichs@smurf.sub.org -- urlichs@smurf.ira.uka.de     /o)\
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