Definition for ethernet flow control packets.

This is a pretty obsolete protocol and ended up not being useful for what I'd hoped it would be, but I wrote an implementation for it anyway so the world might as well have it.

Missing unit test?

AFAIK the standard doesn't give any test vectors, so I'm not sure how to meaningfully test this.

Inventing a test vector myself wouldn't add anything: if there were an error, given the declarative nature of the code here the error would inevitably be a misinterpretation of the standard rather than a mis-implementation of that interpretation -- so adding a test vector I've concocted myself would likely amount to just writing down the same mistake twice.

Would using Wireshark to create the test vector be appropriate here? Given that it's a much more mature project it might not be unreasonable to consider its behavior as "authoritative enough".

Would using Wireshark to create the test vector be appropriate here? Given that it's a much more mature project it might not be unreasonable to consider its behavior as "authoritative enough".

I think using Wireshark or tcpdump to capture a reference/test packet is a good approach.

Thanks!