pstree.x11(1) on Linux
The text 081e42c05f4b, as Debian 6.0 (Squeeze) shipped it.
display a tree of processes
Flags it lists
-
-A -
-G -
-H -
-U -
-V -
-Z -
-a -
-c -
-h -
-l -
-n -
-p -
-u