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From: Baruch Even <baruch@ev-en.org>
To: Stephen Hemminger <shemminger@osdl.org>
Cc: Filipe Abrantes <fla@inescporto.pt>, linux-kernel@vger.kernel.org
Subject: Re: Detecting link up
Date: Wed, 18 May 2005 23:20:35 +0100	[thread overview]
Message-ID: <428BBFB3.4090702@ev-en.org> (raw)
In-Reply-To: <428B876F.8080802@osdl.org>

Stephen Hemminger wrote:
> Filipe Abrantes wrote:
> 
>> Hi all,
>>
>> I need to detect when an interface (wired ethernet) has link up/down.
>> Is there a system signal which is sent when this happens? What is the
>> best way to this programatically?
>>
>> Best Regards
>>
>> Filipe
>>
>>
> 
> The best way is to open a netlink socket and look for the mesaages about
> link up/down there. Read iproute2 http://developer.osdl.org/dev/iproute2
> source for ip command (ipmonitor.c).
> 
> This works for almost all devices unlike ethtool and mii which only
> work on a small subset of devices.

And libnl is a very good library to get just that information without
the need to manually parse netlink messages.

Baruch

      reply	other threads:[~2005-05-18 22:26 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-05-18 10:35 Detecting link up Filipe Abrantes
2005-05-18 11:40 ` Martin Zwickel
2005-05-18 13:11   ` Vaibhav Nivargi
2005-05-18 13:57     ` Richard B. Johnson
2005-05-18 14:37   ` Max Kellermann
2005-05-18 15:00     ` Oliver Neukum
2005-05-18 15:06     ` Coywolf Qi Hunt
2005-05-18 15:11     ` Richard B. Johnson
2005-05-18 17:33   ` Michael Tokarev
2005-05-18 18:20 ` Stephen Hemminger
2005-05-18 22:20   ` Baruch Even [this message]

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