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Subject: Re: svn commit: r265132 - in head: share/man/man4 sys/dev/null
From: Matthew Fleming <mdf@FreeBSD.org>
To: Ian Lepore <ian@freebsd.org>
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On Wed, Apr 30, 2014 at 7:48 AM, Ian Lepore <ian@freebsd.org> wrote:
> On Wed, 2014-04-30 at 06:20 +0000, Eitan Adler wrote:
>> Author: eadler
>> Date: Wed Apr 30 06:20:48 2014
>> New Revision: 265132
>> URL: http://svnweb.freebsd.org/changeset/base/265132
>>
>> Log:
>>   Add a /dev/full device.
>>
>>   /dev/full is similar to /dev/zero except it always returns
>>   ENOSPC when you attempt to write to it.
>>
>
> For some reason this reminded me of something I've been wanting for a
> while but never get around to writing... /dev/ones, it's just
> like /dev/zero except it returns 0xff bytes.  Useful for dd'ing to wipe
> out flash-based media.

dd if=/dev/zero | tr "\000" "\377" | dd of=<xxx>

But it's not quite the same.

Cheers,
matthew