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To: Sam <sah@softcardsystems.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 07 Oct 2004 09:55:25 CDT."
             <Pine.LNX.4.60.0410070951230.25784@athena> 
Date: Thu, 07 Oct 2004 16:25:04 +0200
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cc: John-Mark Gurney <gurney_j@resnet.uoregon.edu>
cc: freebsd-arch@freebsd.org
cc: freebsd-geom@freebsd.org
Subject: Re: fdisk/geom, AoE 5.2.1 
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In message <Pine.LNX.4.60.0410070951230.25784@athena>, Sam writes:

>Arg.  My goof.  I wrote zeros, read zeros and assumed i could
>write to the disk.  In fact I could - even when I wanted to
>read.  I won't go into the details, but suffice it to say you
>can't do:
>
>if (bp->bio_flags & BIO_READ)
> 	// do read
>else
> 	// do write
>
>and expect the correct behaviour. :)

Please be aware that we have _three_ I/O operations under 5.x and
later:  BIO_READ, BIO_WRITE and BIO_DELETE.  Just return EOPNOTSUPP
for BIO_DELETE.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.