iffinder sends UDP packets to ip addresses.  If it receives a ICMP Port
Unreachable error from a different ip address, then the two ip addresses
must be interfaces on the same node.

To build iffinder:
    ./configure
    make

For usage help, type ./iffinder -'?'.  Don't forget to strip bad
addresses (skitter/skadm/conf/badips.config) from the input file.
It prints results to stdout, one line per probe.  The output is
self-documenting.

ifclosure is intended to analyze results of iffinder, but is incomplete.
