From owner-freebsd-scsi  Sat Jan 25 17:29:14 1997
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Date: Sun, 26 Jan 1997 01:29:03 GMT
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From: Richard Tobin <richard@cogsci.ed.ac.uk>
Subject: Re: Tape Backup Drive Not working.
To: joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch),
        freebsd-scsi@FreeBSD.org (FreeBSD SCSI list)
In-Reply-To: J Wunsch's message of Sat, 25 Jan 1997 16:59:49 +0100
Organization: just say no
Cc: chris@bb.cc.wa.us (Chris Coleman)
Sender: owner-freebsd-scsi@FreeBSD.org
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> Hmm.  I wonder if there's any reason to _not_ set the PF bit by
> default?

Well, as you say, all SCSI-2 devices should be happy with it.  On the
other hand, I regard it as a bug that the HP T4000s complains if it's
not set, since there are no parameters being passed that it affects.
Why should it care about the format of zero bytes of data?

I conjecture that Linux sets it by default, since I have heard that
the HP drive worked with Linux without change.

> I'd vote that,
> if we need it at all, we should unset the bit based on some drive's
> quirks, but turn it on by default (in the assumption that most drives
> adhere to SCSI-2).

I agree.

-- Richard