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From: Giorgos Keramidas <keramida@ceid.upatras.gr>
To: Patrick Donnelly <batrick@batbytes.com>
References: <AANLkTin9-MymICgQoSjFlKbLXN2Efm5_3r6X1lufqiCo@mail.gmail.com>
Date: Sat, 10 Jul 2010 11:01:29 +0300
In-Reply-To: <AANLkTin9-MymICgQoSjFlKbLXN2Efm5_3r6X1lufqiCo@mail.gmail.com>
	(Patrick Donnelly's message of "Sat, 10 Jul 2010 03:10:31 -0400")
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Cc: questions@freebsd.org
Subject: Re: Writes to Hard Disk Going Beyond Capacity
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On Sat, 10 Jul 2010 03:10:31 -0400, Patrick Donnelly <batrick@batbytes.com> wrote:
> Hi List,
>
> I have a strange problem in a C program I wrote. I open a hard
> disk character file (/dev/ad1) and attempt to write over the
> entire disk. I expect the last write that would go beyond the
> hard disk length (capacity) to return with an error but instead
> the write succeeds.  This happens for hundreds of gigabytes
> beyond the file (hard drive) length. What could be wrong? (This
> program works fine on Linux. The last write that would go
> beyond the end of the hard drive returns with -1.)
>
> Thanks for any help,

Can we see the exact source code of the program?  What you
describe might work if the file has holes inside it.