From: Bernd Petrovitsch <bernd@firmix.at>
To: Chris Friesen <cfriesen@nortelnetworks.com>
Cc: Oliver Neukum <oliver@neukum.org>,
Steve French <smfltc@us.ibm.com>,
linux-kernel@vger.kernel.org
Subject: Re: upcalls from kernel code to user space daemons
Date: Tue, 15 Jun 2004 00:08:45 +0200 [thread overview]
Message-ID: <1087250925.8828.3.camel@gimli.at.home> (raw)
In-Reply-To: <40CE1F42.1020407@nortelnetworks.com>
On Mon, 2004-06-14 at 23:57, Chris Friesen wrote:
> Oliver Neukum wrote:
>
> > > userspace daemon loops on ioctl()
> > > kernel portion of ioctl call goes to sleep until something to do
> > > when needed, fill in data and return to userspace
> > > userspace does stuff, then passes data back down via ioctl()
> > > ioctl() puts userspace back to sleep and continues on with other work
> >
> > You could just as well implement an ordinary read()
>
> Not quite. The userspace is passing data down as well. I don't know how you'd
> do that with read().
For this you use write().
Bernd
--
Firmix Software GmbH http://www.firmix.at/
mobil: +43 664 4416156 fax: +43 1 7890849-55
Embedded Linux Development and Services
next prev parent reply other threads:[~2004-06-14 22:09 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-06-14 18:07 Steve French
2004-06-14 18:30 ` Chris Friesen
2004-06-14 21:40 ` Oliver Neukum
2004-06-14 21:57 ` Chris Friesen
2004-06-14 22:08 ` Bernd Petrovitsch [this message]
2004-06-14 22:22 ` Chris Friesen
2004-06-14 22:54 ` Tim Hockin
2004-06-14 23:10 ` Randy.Dunlap
2004-06-14 22:54 ` Steve French
2004-06-15 9:06 ` Oliver Neukum
2004-06-18 23:08 ` H. Peter Anvin
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