Arping is an ARP level ping utility.  It's good for finding out if an IP
is taken before you have routing to that subnet.  It can also ping MAC
addresses directly.

It broadcasts a who-has ARP packet on the network and prints answers -
very useful when you are trying to pick an unused IP for a net to which
you don't yet have routing.

This requires libnet.

Note: The installed files are called arping2 to avoid conflicts with
Slackware's arping.