From: Stephen Hemminger <redacted>
Date: Tue, 25 Dec 2007 12:43:23 -0800

The problem is that iproute ss.c needs linux/tcp.h to get the
tcp_info structure definition but linux/tcp.h has incompatible
definitions with netinet/tcp.h.  I propose that the enum be moved
from net/tcp_states.h to linux/tcp.h.

This would be fragile, at best.

We need to solve this in a way such that both linux/tcp.h and
netinet/tcp.h can both be included at the same time by userland.

If we export linux/tcp.h to userspace, we have to make it play nice
with the existing header file namespace.