sockstat(1) on FreeBSD
The text 0bd84eec5f48, as FreeBSD 12.1-RELEASE shipped it.
list open sockets
Flags it lists
-
-4 -
-6 -
-L -
-P -
-S -
-U -
-c -
-j -
-l -
-p -
-q -
-s -
-u -
-v -
-w