Subject: Re: representation of persistent device status, was Re: devfs, was Re: ptyfs...
To: Bill Studenmund <>
From: Jason Thorpe <>
List: tech-kern
Date: 11/24/2004 14:00:07
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On Nov 19, 2004, at 6:41 PM, Bill Studenmund wrote:

> I would suggest an alternate for "duplicate" devfs mounts - new 
> hardware
> doesn't automatically appear in them. They only list whatever nodes the
> admin has included in them.

Take that a bit further...

The filter provides a list of things that MAY be presented in the view 
IF they exist.  Obviously, if sd0 doesn't exist, then it should not be 
listed in the view, even if the view's filter allows for it.  Likewise, 
if it disappears, it should disappear from all views.

That said, I'm suspecting that most views are going to want just basic 
pseudo-device files (/dev/null, etc.) and so this won't be much of an 

But, I think name-based filtering with associated permissions can do 

Basically, each "view" of the devfs would get its own set of internal 
directory entries, which in turn refer back to the actual object that 
represents the device.

         -- Jason R. Thorpe <>

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