From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [RFC] O_NOACC: open without any access
Date: Tue, 23 Jun 2009 12:53:37 -0400
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Cc: Miklos Szeredi <miklos@szeredi.hu>, hch@infradead.org,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	torvalds@linux-foundation.org, viro@ZenIV.linux.org.uk,
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To: David Howells <dhowells@redhat.com>
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On Tue, Jun 23, 2009 at 04:52:17PM +0100, David Howells wrote:
> Miklos Szeredi <miklos@szeredi.hu> wrote:
> 
> > Right, but that makes it useless for things which want to open it
> > despite having no permission on the file.
> 
> For my purposes, if I'm going to emulate pioctl() in userspace, I also need to
> be able to open device files that don't have drivers available, and when you
> do open a dev file in this manner, it must _not_ call the ->open() routine of
> the device driver.

Last time I checked afs didn't support device files at all.  And limited
the magic commands to not work on device files doesn't sound to bad.

Of course specifying what these magic tools are actually supposed to do
would be an interesting start.