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From: Terry Lambert <terry@lambert.org>
Message-Id: <199707290003.RAA01897@phaeton.artisoft.com>
Subject: Re: Location of copyin() and copyout()..
To: vinay@agni.nuko.com (Vinay Bannai)
Date: Mon, 28 Jul 1997 17:03:00 -0700 (MST)
Cc: freebsd-hackers@FreeBSD.ORG
In-Reply-To: <199707282150.OAA01303@agni.nuko.com> from "Vinay Bannai" at Jul 28, 97 02:50:17 pm
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> I was wondering if it is considered a good idea to move data back and
> forth between the user and kernel space using copyin() and copyout()
> without calling uiomove(). I can't seem to find the location of these
> functions/macros. Can someone point me where they are defined??

They are kernel intrinsics.

It's OK to use them, if you aren't using them for an I/O buffer.  The
primary reason to use UIO is that it handles user I/O request, ie: it
does buffer paging correctly, and anonymously.

There are lots of places where copyin/copyout is used (ioctl()
paramters, the path name copy in namei(), etc.).


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.