postconf(1) on macOS
The text fef8925d1fc6, as OS X 10.9.5, OS X 10.9.4, OS X 10.9.3, OS X 10.9.2, OS X 10.9.1, OS X 10.9, Mac OS X 10.8.5, Mac OS X 10.8.4, Mac OS X 10.8.3, Mac OS X 10.8.2, Mac OS X 10.8.1, Mac OS X 10.8 shipped it.
Postfix configuration utility
Flags it lists
-
-# -
-A -
-C -
-M -
-a -
-b -
-c -
-d -
-e -
-f -
-h -
-l -
-m -
-n -
-t -
-v