From owner-freebsd-hackers@FreeBSD.ORG Mon Jan 24 19:13:02 2005 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1C08B16A4CE for ; Mon, 24 Jan 2005 19:13:02 +0000 (GMT) Received: from ebb.errno.com (ebb.errno.com [66.127.85.87]) by mx1.FreeBSD.org (Postfix) with ESMTP id B397A43D31 for ; Mon, 24 Jan 2005 19:13:01 +0000 (GMT) (envelope-from sam@errno.com) Received: from [66.127.85.91] (sam@[66.127.85.91]) (authenticated bits=0) by ebb.errno.com (8.12.9/8.12.6) with ESMTP id j0OJCtWi006041 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Mon, 24 Jan 2005 11:12:56 -0800 (PST) (envelope-from sam@errno.com) Message-ID: <41F548D6.9060409@errno.com> Date: Mon, 24 Jan 2005 11:13:26 -0800 From: Sam Leffler User-Agent: Mozilla Thunderbird 1.0RC1 (X11/20041208) X-Accept-Language: en-us, en MIME-Version: 1.0 To: ticso@cicely.de References: <20050124083043.GA8729@kukulies.org> <20050124151612.GC628@cicely12.cicely.de> <20050124124250.A27718@pix.net> <20050124180840.GH628@cicely12.cicely.de> In-Reply-To: <20050124180840.GH628@cicely12.cicely.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit cc: hackers@freebsd.org cc: "Kurt J. Lidl" Subject: Re: ttyd0/cuad0 - why is there still this duality ? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 24 Jan 2005 19:13:02 -0000 Bernd Walter wrote: > On Mon, Jan 24, 2005 at 12:42:50PM -0500, Kurt J. Lidl wrote: > >>On Mon, Jan 24, 2005 at 04:16:13PM +0100, Bernd Walter wrote: >> >>>On Mon, Jan 24, 2005 at 09:30:43AM +0100, Christoph P. Kukulies wrote: >>> >>>>Just a question. Maybe it isn't true but to me it seems there >>>>is still this duality between ttyd and cuad serial devices. >>>> >>>>Why is that? I'm just asking because someone I was talking with >>>>about modems an comm programs was 'criticising' this fact >>>>in FreeBSD "while other systems long have abandoned this dualism"? >>> >>>Because modems are still used for dial-in and dial-out. >>>tty handing out to getty and cua to the dial out process. >>>Moreover this handling was recently added for usb serials under >>>-current. >>>If other systems loose features - well it's their problem. >> >>That's a very limited way of looking at the functionality. If you >>want to support the functions of both dialin and dialout on one >>serial port, there doesn't need to be more than one kernel device. >>Just because support for this got hacked into 4.2BSD in a gross >>manner doesn't mean that there isn't a better of doing this. > > > You still have the option to just ignore existenz of tty* devnodes. > > >>Having seperate dialout and dialin devices really are just a kludge >>for having the kernel doing locking that could be done in userland >>code. > > > tty* vs cua* is more than just locking. > > >>Just because FreeBSD does this the same way it's been done on >>BSD-ish systems for the last 15 years doesn't mean there isn't a >>better way of doing it. > > > Yes, but this way it just works and applications used it for many > years. > Portable modem-aware applications have never used it (speaking as someone that wrote many modem-oriented applications like tip and hylafax). I've never found a case where you cannot implement the equivalent functionality outside the kernel. Sam