Re: [mdnsext] Discussion of BoF during Berlin IETF

Michael Sweet <> Tue, 11 June 2013 11:56 UTC

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From: Michael Sweet <>
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Date: Tue, 11 Jun 2013 07:55:53 -0400
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To: "Albrecht, Harald" <>
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Subject: Re: [mdnsext] Discussion of BoF during Berlin IETF
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On 2013-06-11, at 5:08 AM, "Albrecht, Harald" <> wrote:
> ... 
> My analysis bases on the GNU libc as one example, other implementations may differ very well (and most probably will). Code base is glib 2.17 as available from the FSF ftp servers. I tried to make sure that I did not make any (gross) mistakes in my analysis. However, caveat emptor, and if you find errors in my analysis please explain them to us so I (and maybe others) can learn.

As a user of getaddrinfo, I know for sure that the AI_IDN flag is a non-standard glibc extension.  And IMHO it is a poorly thought-out addition to the API - such decisions need to be made in the underlying resolvers (all those plugins you can specify in /etc/nsswitch.conf for "hosts") and not in the application which then needs to have a much greater understanding of which DNS is being used, etc.  The original proposal [1] gives some background on the addition, but I personally would not rely on the application asking the system to Do The Right Thing (tm).


Michael Sweet, Senior Printing System Engineer, PWG Chair