From owner-freebsd-hackers@FreeBSD.ORG Mon Apr 10 13:14:08 2006 Return-Path: X-Original-To: hackers@freebsd.org 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 7DC8A16A402 for ; Mon, 10 Apr 2006 13:14:08 +0000 (UTC) (envelope-from babkin@verizon.net) Received: from vms042pub.verizon.net (vms042pub.verizon.net [206.46.252.42]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3DCFA43D45 for ; Mon, 10 Apr 2006 13:14:08 +0000 (GMT) (envelope-from babkin@verizon.net) Received: from vms069.mailsrvcs.net ([192.168.1.2]) by vms042.mailsrvcs.net (Sun Java System Messaging Server 6.2-4.02 (built Sep 9 2005)) with ESMTPA id <0IXI00261CRGL422@vms042.mailsrvcs.net> for hackers@freebsd.org; Mon, 10 Apr 2006 08:14:05 -0500 (CDT) Date: Mon, 10 Apr 2006 08:14:04 -0500 (CDT) From: Sergey Babkin To: "M. Warner Losh" , mwm-keyword-freebsdhackers.102a7e@mired.org Message-id: <7062548.1416391144674845516.JavaMail.root@vms069.mailsrvcs.net> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1 Content-transfer-encoding: 7bit X-Mailman-Approved-At: Mon, 10 Apr 2006 14:35:39 +0000 Cc: ceri@submonkey.net, babkin@users.sourceforge.net, hackers@freebsd.org, scottl@samsco.org Subject: Re: Re: What's in a (device) name? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: babkin@users.sf.net List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 Apr 2006 13:14:08 -0000 >From: "M. Warner Losh" >usb assigns addresses dynamically. Everyone else does it basically >statically. PCI slot/device numbers are static, but extreme >configurations can change the bus number. Some USB devices (though not all of them) provide a unique device ID. If this ID is available, binding to a particular device is straightforward. The problems start when the device get replaced. For example, an USB printer dies and you replace it with another one. Form a tech support standpoint it's convenient if the new printer gets silently recognized as a replacement of the old one. -SB