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Date: Wed, 02 Dec 2009 09:46:18 -0600
From: Anthony Liguori <anthony@codemonkey.ws>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] [PATCH, RFC] tap-linux: support opening arbitrary
	char devices
References: <200911262034.04440.arnd@arndb.de>
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To: Arnd Bergmann <arnd@arndb.de>
Cc: qemu-devel@nongnu.org

Arnd Bergmann wrote:
> With the upcoming macvtap, we will want to open devices other than
> /dev/net/tun but no longer need to call TUNSETIFF.
>   

What are the names of these devices and how do you the character devices 
get created in the first place?

This really isn't an "arbitrary" char device as it doesn't implement the 
same interface as tap.  Creation is done in a different manner.

> This makes it possible to do 'qemu -net tap,ifname=/dev/tap/macvtap0'
> to refer to a chardev in addition to the current way of doing
> 'qemu -net tap,ifname=tap0' to refer to a tap network interface
> set with TUNSETIFF. This is consistent with what we do on BSD.
>   

We definitely don't want to overload ifname like this.  
/dev/tap/macvtap0 is clearly not the interface name.

Regards,

Anthony Liguori