u2f-host(1) on Linux
The text c0639b893427, as Debian 9 (Stretch) shipped it.
Yubico Universal 2nd Factor (U2F) Host Tool
Flags it lists
-
--action -
--command -
--debug -
--help -
--origin -
--touch -
--version -
-V -
-a -
-c -
-d -
-h -
-o -
-t