Since I decided to enable IPv6, I needed an IPv6-enabled tcpdump. So, I got tcpdump 3.5 and it understands IPv6 fine, but it can only show one interface at a time.

I decided, then, to write a small wrapper program that would run several tcpdumps, one on each interface, and parse the output into a simple output, indicating the interface the packet came from.

I'm calling it allifdump.