"But while it's all easily parsed if you need it, there aren't
really any tools around that do it for you. That is... except for
libpcap. Libpcap is the power behind the throne of the venerable
tcpdump tool. Tcpdump is not much more than a command line parser
and pretty-printer of various network protocols. The heavy duty
lifting is done by libpcap, not least by providing a cross-platform
API for sniffing devices, something that is otherwise non-standard
and different on every platform. It's great, I've used it before
(in capstats) and it's very easy to use.
"Libpcap on linux supports usbmon sniffing, which means you can
use tcpdump to sniff a USB port and write this to a capture file.
But best of all: wireshark, the all-singing all-dancing network
analyzer that uses tcpdump capture files, has USB support as well.
So this is the result:"