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From: David Dawes <dawes@rf900.physics.usyd.edu.au>
Message-Id: <199512310311.OAA16531@rf900.physics.usyd.edu.au>
Subject: Re: /dev/io
To: jkh@time.cdrom.com (Jordan K. Hubbard)
Date: Sun, 31 Dec 1995 14:11:20 +1100 (EST)
Cc: hackers@freebsd.org
In-Reply-To: <8724.820374911@time.cdrom.com> from "Jordan K. Hubbard" at Dec 30, 95 05:55:11 pm
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>> To me it seems like it would be more "standard" if FreeBSD supported an
>> implementation like NetBSD's.  It would also pave the way for the
>> implementation of IO permission bitmaps (if they are ever needed).  Changing
>> it would probably be a little more secure, and I can't even think of any 
>> programs that would break if /dev/io was removed?
>
>I think a few X servers would definitely break of /dev/io went away
>suddently, but I also see no reason why the other interface couldn't
>be implemented in parallel with a change-over at some point in the
>future.

For what it's worth, the XFree86 servers get I/O permission by using
the KDENABIO ioctl in the console driver rather than by opening /dev/io.

David