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Date: Mon, 1 Dec 1997 11:52:28 -0800
From: "Fred L. Templin" <templin@erg.sri.com>
To: freebsd-hackers@FreeBSD.ORG
Cc: templin@erg.sri.com
Subject: copyout()/copyin()
Sender: owner-freebsd-hackers@FreeBSD.ORG
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Hi,

I'm designing an interface in which I need to move data directly between
user and kernel buffers using copyout() and copyin(). The interface works
fine when called synchronously within process context (e.g. the user process
calls ioctl(), giving the address of a buffer, and the kernel calls copyout()
or copyin() to move the data). But, what I really want is an *asynchronous*
interface in which the kernel can move data to/from the user buffers from
within an interrupt service routine - and it's my understanding that copyout()
and copyin() aren't suited for this. Am I wrong about this? If not, are there
alternatives to copyout()/copyin() which can be used to implement such an
interface?

Fred
templin@erg.sri.com