I wrote pinger - ping a range of hosts some time ago, which offers one Way To Do it. The main trick is to mark the script setuid root, in order to use ICMP packets. None of my machines respond to TCP or UDP echo packets, and I see no reason for that to change.

I don't really see the use for an array interface. If you feed an array in, you have to parse an array coming out, and match up what output corresponds to what input. Sounds like a lot of fiddly housekeeping details to me.