From owner-freebsd-current Thu Jan 20 9: 7:21 2000 Delivered-To: freebsd-current@freebsd.org Received: from mumble.frotz.net (mumble.frotz.net [216.15.97.250]) by hub.freebsd.org (Postfix) with SMTP id 08AFF15243 for ; Thu, 20 Jan 2000 09:07:19 -0800 (PST) (envelope-from swetland@frotz.net) Received: (qmail 33725 invoked by uid 1000); 20 Jan 2000 17:09:13 -0000 Date: Thu, 20 Jan 2000 09:09:13 -0800 From: "Brian J. Swetland" To: current@freebsd.org Subject: Re: devfs? Message-ID: <20000120090913.A32362@frotz.net> References: <20000119214258.A29986@frotz.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.6us In-Reply-To: <20000119214258.A29986@frotz.net>; from Brian J. Swetland on Wed, Jan 19, 2000 at 09:42:58PM -0800 Organization: Frotz Communications, Ltd. X-Mailer-Holy-War: Get Mutt, it bites! Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG ["Brian J. Swetland" ] > > I'm interested in mucking about with the devfs stuff a bit -- is there > currently any active developer/maintainer/docs? I grabbed the 4.0 > snapshot from the 17th, installed it, grabbed the kernel sources from > CVS, got stuff building and figured out how to enable DDB (not that > much different from the kdebug environment I'm used to from BeOS). I > figured I'd see if there was any more information than the sources. I see (after digging through some recent list archives) that I missed some discussion of this from as recent as a week ago. Also I notice that devfs does build, is mountable, is mountable, and shows a goodly number of the active devices in my system. Somebody mentioned the issue of figuring out when things change in sysctl/devfs/etc (and please excuse me if we've been here before), but there seem to be two non-polling solutions that are workable (though the second is much more work). Either provide /dev/devchanges or whatnot that interested processes can read (and block on) to receive change events (similar to the Linux cardmgr socket stuff) or provide general node monitoring (where processes can register for notifications for move/modify/remove/directorychanged with some entity that plugs into the vfs layer). The latter has some really neat effects (which BeOS makes heavy use of) generally involving not needing to poll for fs changes (input server node monitors /dev/input/... and sees new mice, etc as they're plugged in, GUI file browser gets events when third parties modify stuff in open windows, etc). Also, if anyone did reply to me over the last day or two, I've been having entertaining mail problems (now resolved) which probably resulted in me missing the reply. Brian -- Brian Swetland - swetland@frotz.net | "If I have hacked deeper than them, it http://www.frotz.net/swetland/ | is because I stand in their trenches." | -- Graham Nelson To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message