1This is a simple program which demonstrates how to query the kernel 2routing mechanism using only a UDP socket. Pass it a hostname on 3the command line (sorry, it doesn't parse dotted decimal) and it will 4print out an IP address which names the interface over which UDP 5packets intended for that destination would be sent. 6A more sophisticated program might use the list obtained from SIOCGIFCONF 7to match the address with an interface name, but applications programmers 8much more often need to know the address of the interface rather than 9the name. 10