Were A record domain names ever limited to 23 characters?

Joe Hamelin joe at nethead.com
Sat Oct 8 03:49:25 UTC 2011

On Fri, Oct 7, 2011 at 8:25 PM, Owen DeLong <owen at delong.com> wrote:
>Yes, this was because some very old (current at the time, however)
>implementations of gethostbyname(3) were implemented in such a way that if
>the first character they saw returned isdigit()==TRUE, then,
>they would assume that they had been passed an IP address
>and would attempt to encode the string as an IP address rather
>than looking it up in /etc/hosts or DNS.

Now I'm going to have to look at the current gethostbyname(3) and see what
happens if we ever get a tld that is a decimal number under 255.  Yet
another reason for IPv6.

Joe Hamelin, W7COM, Tulalip, WA, 360-474-7474

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