What: resolver - Asynchronous name resolution
Who: Pat Thoyts
Where: http://www.patthoyts.tk/tclresolver/index.html 
Description: Performs non-blocking name resolution for Windows. At the moment 
     this package just creates a resolve command and then talks to the slave. Testing 
     this gives me a Tk application that continues to process events and update the 
     display while waiting for slow responses (i.e., DNS queries for non-existant hostnames).