sockstat(1) on Linux
The text e36598588c72, as Debian 9 (Stretch), Debian 8 (Jessie), Debian 7 (Wheezy), Debian 6.0 (Squeeze) shipped it.
list open sockets
Flags it lists
-
-G -
-P -
-U -
-c -
-h -
-l -
-p