diff(1) on OpenBSD
The text d51debacb0ba, as OpenBSD 4.4, OpenBSD 4.3, OpenBSD 4.2 shipped it.
differential file and directory comparator
Flags it lists
-
-C -
-D -
-I -
-L -
-N -
-P -
-S -
-T -
-U -
-X -
-a -
-b -
-c -
-d -
-e -
-f -
-i -
-l -
-n -
-p -
-q -
-r -
-s -
-t -
-u -
-w -
-x