ipnat(8) on FreeBSD
The text aae8f9d8c68b, as FreeBSD 6.3-RELEASE, FreeBSD 6.2-RELEASE shipped it.
user interface to the NAT subsystem
Flags it lists
-
-C -
-F -
-d -
-h -
-l -
-n -
-r -
-s -
-v