[Boost-users] [asio] How to get the name of the endpoint from the ip address of the endpoint.

Subject: [Boost-users] [asio] How to get the name of the endpoint from the ip address of the endpoint.
From: Andrew Maclean (andrew.amaclean_at_[hidden])
Date: 2009-02-02 19:44:59

If I have an endpoint as an ip address (IP V4 or IPv6), how can I do a
DNS lookup to get the name of the endpoint?
In the example below, I understand that the host_name is coming from
the query. But how do I do a lookup to get the host name from the IP?

This may help.

If I do something like this:
    ip::tcp::resolver_iterator res =
ip::tcp::resolver(ios).resolve(ip::tcp::resolver_query("google.com",
"80"));
    for(;res != ip::tcp::resolver_iterator(); ++res)
    {
      std::cout << res->host_name() << ":" << res->service_name() << " ";
      std::cout << res->endpoint().address().to_string() << std::endl;
    }
   The the output is:
google.com:80 209.85.171.100
google.com:80 74.125.67.100
google.com:80 74.125.45.100

However if I do:
    ip::tcp::resolver_iterator res =
ip::tcp::resolver(ios).resolve(ip::tcp::resolver_query("209.85.171.100",
"80"));

I get:
209.85.171.100:80 209.85.171.100
so th ehosr name comes from the query.

I really want:
google.com:80 209.85.171.100

Thanks in advance for any help.

Andrew

-- 
___________________________________________
Andrew J. P. Maclean
Centre for Autonomous Systems
The Rose Street Building J04
The University of Sydney  2006  NSW
AUSTRALIA
Ph: [phone]
Fax: [phone]
URL: http://www.acfr.usyd.edu.au/
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