From owner-freebsd-usb@FreeBSD.ORG  Tue May 24 19:22:22 2005
Return-Path: <owner-freebsd-usb@FreeBSD.ORG>
X-Original-To: freebsd-usb@freebsd.org
Delivered-To: freebsd-usb@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 7D03916A41C
	for <freebsd-usb@freebsd.org>; Tue, 24 May 2005 19:22:22 +0000 (GMT)
	(envelope-from hselasky@c2i.net)
Received: from swip.net (mailfe01.swip.net [212.247.154.1])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 0ED6143D48
	for <freebsd-usb@freebsd.org>; Tue, 24 May 2005 19:22:18 +0000 (GMT)
	(envelope-from hselasky@c2i.net)
X-T2-Posting-ID: Y1QAsIk9O44SO+J/q9KNyQ==
Received: from mp-217-200-254.daxnet.no ([193.217.200.254] verified)
	by mailfe01.swip.net (CommuniGate Pro SMTP 4.3c5)
	with ESMTP id 379462787; Tue, 24 May 2005 21:22:06 +0200
From: Hans Petter Selasky <hselasky@c2i.net>
To: freebsd-usb@freebsd.org,
 Dirk Gouders <gouders@et.bocholt.fh-ge.de>
Date: Tue, 24 May 2005 21:22:52 +0200
User-Agent: KMail/1.7
References: <200505241053.j4OArR2c000390@musashi.et.bocholt.fh-gelsenkirchen.de>
In-Reply-To: <200505241053.j4OArR2c000390@musashi.et.bocholt.fh-gelsenkirchen.de>
MIME-Version: 1.0
Content-Type: text/plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Message-Id: <200505242122.53801.hselasky@c2i.net>
Cc: 
Subject: Re: poll(2)ing or select(2)ing /dev/usb0
X-BeenThere: freebsd-usb@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
Reply-To: hselasky@c2i.net
List-Id: FreeBSD support for USB <freebsd-usb.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-usb>,
	<mailto:freebsd-usb-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-usb>
List-Post: <mailto:freebsd-usb@freebsd.org>
List-Help: <mailto:freebsd-usb-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-usb>,
	<mailto:freebsd-usb-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 24 May 2005 19:22:22 -0000

On Tuesday 24 May 2005 12:53, Dirk Gouders wrote:
> Hello,
>
> in the section USB CONTROLLER INTERFACE the manual page usb(4) says
> that one can use poll(2) on /dev/usbN to get noticed when USB devices
> are connected or disconnected.
>
> Now, I wrote two small programs to play with poll(2) and select(2)
> on /dev/usb0 and see what happens if I connect/disconnect a USB
> device, but nothing happens.  As the manual page does not say
> what events to poll(2) for, I just turned on all bits in the events
> mask and the programs work fine on the event interface /dev/usb.
>

You cannot read data from /dev/usbN, only ioctls are possible on those 
devices.

See "/sys/dev/usb/usb.c" (usbpoll), if you got the source code installed.

--HPS