tmate(1) on Linux
The text 5aa9eba083f2, as Debian 10 (Buster), Debian 9 (Stretch) shipped it.
terminal multiplexer with instant terminal sharing
Flags it lists
-
-2 -
-C -
-L -
-S -
-V -
-c -
-f -
-l -
-u -
-v