From owner-freebsd-current@FreeBSD.ORG Mon May 26 15:26:14 2008 Return-Path: Delivered-To: current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D3C44106567B; Mon, 26 May 2008 15:26:14 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from cyrus.watson.org (cyrus.watson.org [209.31.154.42]) by mx1.freebsd.org (Postfix) with ESMTP id 9FD208FC29; Mon, 26 May 2008 15:26:14 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from fledge.watson.org (fledge.watson.org [209.31.154.41]) by cyrus.watson.org (Postfix) with ESMTP id 2781F46B42; Mon, 26 May 2008 11:26:14 -0400 (EDT) Date: Mon, 26 May 2008 16:26:14 +0100 (BST) From: Robert Watson X-X-Sender: robert@fledge.watson.org To: "Bruce M. Simpson" In-Reply-To: <483AD498.6070207@FreeBSD.org> Message-ID: <20080526162427.X26343@fledge.watson.org> References: <20080524111715.T64552@fledge.watson.org> <1211640498.1510.8.camel@localhost> <20080524165519.K9809@fledge.watson.org> <20080525105726.O39741@fledge.watson.org> <5D4AF8D7-88A7-4197-A0FE-7CA992EE5F96@FreeBSD.org> <483AD498.6070207@FreeBSD.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: arch@freebsd.org, current@freebsd.org, Ade Lovett , net@freebsd.org Subject: Re: HEAD UP: non-MPSAFE network drivers to be disabled (was: 8.0 network stack MPsafety goals (fwd)) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 26 May 2008 15:26:15 -0000 On Mon, 26 May 2008, Bruce M. Simpson wrote: >> Given that this is (a) 2008 and (b) 8.x we're talking about, are there >> really that many consumers of SLIP to warrant it being carried forward at >> all? > > It's kind of a basic. [C]SLIP has been historically handy to have around for > situations which warrant it. Mind you, given that we have had tun(4) in the > tree for years now, a userland implementation of SLIP is possible. > > As with all of these things it's down to someone sitting down and doing it. > > I'm not volunteering to support any of this as I don't use it myself (got > enough on my plate), merely pointing out that support for SLIP in a system > is something many people have taken for granted over the years, and for > prototyping something or providing IP over a simple serial link without the > configuration overhead of PPP, SLIP is something someone might be using. > > P.S. ahc(4) is commodity hardware, I think it can stay right where it is > thank-you. My suspicion is that getting SLIP basically working in userspace is fairly straight forward, although I'm not sure how well-suited some of our current admin tools (slattach, etc) are for the purpose. If the new tty code maintains support for line disciplines, updating the existing SLIP code and adding locking code would probably be an equally sized (or shorter) task. SLIP has its subtleties, but the current implementation is relatively straight-forward, well-documented, etc. Robert N M Watson Computer Laboratory University of Cambridge