Posted by Malcolm Dew-Jones on 10/28/48 11:33

Michael (INERFAZE@aol.com) wrote:

: I just tried a fixed IP of Microsoft $domain=GetHostByAddr("207.46.20.30");
: and that didn't work either.

But it did work! It just didn't do what you wanted it to do. It returned
the information that was made visible to the host that ran the command -
in other words, no information.

That is exactly why someone originally said this was "fraught" with
problems.

You can only get the reverse lookup if an appropriate name server makes
that information available to you, and they commonly don't do that. Even
if the information is available to _some_ people on one network, _you_
will not be able to get it unless that name server is visible to you.
For example I have my own resolver setup at home, and I can assign names
to my machines, but my name server setup is not visible to you and so you
cannot get that information. Lots of machines have names that are only
visible to some internal network, even if the ip address of that machine
can access the world.

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