From mboxrd@z Thu Jan  1 00:00:00 1970
From: Prashant Batra <prbatra.lists@gmail.com>
Subject: attach multiple programs to tun/tap interface
Date: Mon, 01 Apr 2013 22:42:21 +0530
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Hi,

I have a basic query on tun/tap driver design. Is it possible to attach=
=20
multiple user-space programs to the same tun/tap interface. I have not=20
set the interface as EXCLUSIVE,
but still on trying to do ioctl with cmd as =93TUNSETIFF=94 from the se=
cond=20
user space program, I get =93Device busy=94.

Seeing through the driver code, it looks like it does not allow multipl=
e=20
user-programs to attach to the same interface, but is this valid, and=20
please let me know why this requirement was taken.

Will you please help me in understanding this?

Thanks,
Prashant