sftp-server(8) on macOS
The text 021d40dbe477, as macOS 12.5, macOS 12.4, macOS 12.3, macOS 12.2, macOS 12.1, macOS 12.0.1 shipped it.
OpenSSH SFTP server subsystem
Flags it lists
-
-P -
-Q -
-R -
-d -
-e -
-f -
-h -
-l -
-p -
-u