CFLib.org – Common Function Library Project

Description:
DNS lookup, provide an IP address, it'll return a host name. If the address is invalid an exception will be throw, so <CFTRY>/<CFCATCH> should be used.

Return Values:
Returns a domain name.

Example:

<CFOUTPUT>
#GetHostName(CGI.REMOTE_ADDR)#<br>
<i>Note, since we cache pages, the result of this test will not reflect your remote address.</i>
</CFOUTPUT>

Parameters:

Full UDF Source:

/**
 * Performs a DNS lookup on an IP address.
 * 
 * @param address      IP address to look up. 
 * @return Returns a domain name. 
 * @author Ben Forta (ben@forta.com) 
 * @version 1, December 19, 2001 
 */
function GetHostName(address) {
   // Variables
   var iaclass="";
   var addr="";
   
   // Init class
   iaclass=CreateObject("java", "java.net.InetAddress");

   // Get address
   addr=iaclass.getByName(address);

   // Return the name    
   return addr.getHostName();
}