From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <f28533bc058a55886d97cdf9f859d297@coraid.com>
From: erik quanstrom <quanstro@coraid.com>
Date: Wed, 18 Oct 2006 15:30:28 -0400
To: 9fans@cse.psu.edu
Subject: Re: [9fans] csipinfo
In-Reply-To: <0fcc387289a4a346cbd5bf450171a0d0@plan9.jp>
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> Thanks, this finally looks like what I need.  Two points though:
> 1.  Is 64 bytes sufficient for the domain name?  Searching the =E2=80=99=
net
> I=E2=80=99ve found other numbers =E2=80=94 according to <http://tinyurl=
.com/ykyths> it
> should be 1005; <http://tinyurl.com/xdp4> links to a name about 140
> bytes long and firefox handles it just fine.

this was throwaway code.  i didn't think very hard about that number.
ndb does have a maximum value length of 64 bytes.

; g -i max /sys/src/cmd/ndb/dns.h:
dns.h:68: 	Domlen=3D		256,	/* max domain name length (with NULL) */

> 2. Why the second part of =E2=80=9Cif(l < 0 || l =3D=3D sizeof buf)=E2=80=
=9D?

room for the terminating null.

as pointed out, this doesn't quite work. you have to reverse the dots you=
rself and add in-addr.arpa.
the code is in /sys/src/cmd/ndb/dnsquery.c

- erik