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Date: Sun, 6 Feb 2005 05:39:57 -0800 (PST)
From: "Kamal R. Prasad" <kamalpr@yahoo.com>
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Subject: Re: Opening and wriiting to file in Kern
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--- Peter Pentchev <roam@ringlet.net> wrote:

> On Sun, Feb 06, 2005 at 04:22:41AM -0800, Kamal R.
> Prasad wrote:
> > 
> > --- Scott Long <scottl@freebsd.org> wrote:
> > 
> > > Ashwin Chandra wrote:
[snip]

> > facility. I don't see anything wrong with
> providing a
> > stream (like) interface to the filesystem.
> 
> While there might indeed be nothing wrong with it,
> besides added
> complexity, the traditional way to do it would be to
> have a userland
> configuration utility that communicates with the
> kernel module either
> via ioctl's on some standard device, or via ioctl's
> or reading/writing
> of a driver-specific device.  This has the advantage
> of being a bit more
> portable - while different OS's implement disk/file
> I/O within the
> kernel in wildly different ways, all OS's provide
> relatively simple ways
> for a kernel module to define a new device and
> handle ioctl's to it, and
> all OS's provide basically the same
> userland-to-kernel interface for
> having a program open a device and issue ioctl's to
> it :)
> 

No doubt about the portability aspect. But there are
situations wherein the kernel does *NOT* want userland
to know that it is using the filesystem for providing
some functionaality. For a device, it is indeed
typical for a userland program to accompany the
driver. But besides that, there are definately
situations (1 of which I am dealing with) wherein
there is no userland code to help one out.

[snip]

regards
-kamal




		
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