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Re: Is tun(4) a cloning device?

    Date:        Fri, 25 Dec 2015 00:20:56 +0100
    From:        Rhialto <>
    Message-ID:  <>

  | Grom reading the source, net/if_tun.c, I get the impression that tun is
  | a cloning device. Like tap. 

It is a cloning device, but not quite like tap.

It is a cloning device, in the sense that there is no magic number of
tunnel devices configured into the kernel, which you cannot exceed at
run time - if you want tap999 just ifconfig it (ifconfig tun999 create)
and it exists.   This is how most cloning pseudo-devices work, and it
means that when you use it, you know in advance which interface number
you're getting (you choose).

However, it does not have the magic minor device that creates a new
interface every time it is opened (the /dev/tap equivalent).


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