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To: Terry Lambert <terry@lambert.org>
cc: current@FreeBSD.ORG
Subject: Re: DISCUSS: system open file table 
In-reply-to: Your message of "Thu, 03 Apr 1997 16:28:39 MST."
             <199704032328.QAA17735@phaeton.artisoft.com> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Thu, 03 Apr 1997 16:36:50 -0800
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>4)	Any other kernel file I/O operations which rely
>	on stored credentials established at file open(*).
>
>	(*) The descriptor f_type and f_ops field are not
>	    relevent arguments in favor of this, since they
>	    are cruft which should be diked out.

   It's already trivially easy to do file I/O in the kernel without a file
descriptor. As you know, a "file descriptor" in FreeBSD is only a mechanism
to translate a per-process file handle to a kernel vnode. For this reason,
the very notion of a "file descriptor" is only relevant in the context of
a process. It sounds like #4 is the main thing you're after, but I fail to
see how this is relevant unless you have a process context in which to do
the I/O, and in that case you already have easy access to the process'
credentials.

-DG

David Greenman
Core-team/Principal Architect, The FreeBSD Project