Perhaps you misunderstood my statement I am not talking about NT there, Spider Systems has had their network user spaces utilities and tools but almost all of them were BSD not developed by them. If their tools originally BSD then what were the chances they developed their very own TCP/IP stacks from scratch with good compatibility with the outside world?

This remind me a particular incident happened to Brendan Gregg of the eBPF initiatives, when a company performed a demo of their alleged game changing kernel tracing tools to him and as it turned out the tools were actually Brendan very own developed tools.