ssh-agent(1) on macOS
The text c315a1b3b85c, as macOS 10.12.3, macOS 10.12.2, macOS 10.12.1, macOS 10.12 shipped it.
authentication agent
Flags it lists
-
-D -
-E -
-a -
-c -
-d -
-k -
-s -
-t