Alun wrote:
>Marc Perkel <marc@???> said, in message
>432E4B47.9070409@???:
>
>
>
>>New revised code at bottom.
>>
>>If the part second to the end is co com net org then it's 3 part.
>>
>>
>
>Where should news.com.com be split up?
>
>
com.com
>What would you want for www.aber.ac.uk?
>
>
aber.ac.uk
>How about www.alumni.aber.ac.uk?
>
>
aber.ac.uk
>Or something.demon.co.uk?
>
>
demon.co.uk
How many can there be? It may take a table ot DB file to pull it off but
I don't think that it would be much more than 100 entries.
>Determining a suitable subdomain is a black art. I tried it a few
>years ago for spam reporting (back when it was actually useful to
>do such). Best I could do was something like (feel free to criticise!):
>
>function maildomain(name)
>{
> domain = ""
> mx = ""
>
> # Find longest "domain" part which has an MX lookup.
> while (name <> "")
> {
> mx = mx lookup for name
> if (mx <> "")
> {
> domain = name
> break;
> }
> strip first component from name
> }
>
> # Find shortest "domain" part which has the same MX lookup.
> while (name <> "")
> {
> mx2 = mx lookup for name
> if (mx2 == mx)
> {
> domain = name
> }
> else
> {
> break;
> }
> strip first component from name
> }
> return domain
>}
>
>Cheers,
>Alun.
>
>
>
>
--
Marc Perkel - marc@???
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