signify(1) on OpenBSD
The text 86d13e91ec21, as OpenBSD 6.4 shipped it.
cryptographically sign and verify files
Flags it lists
-
-C -
-G -
-S -
-V -
-c -
-e -
-m -
-n -
-p -
-q -
-s -
-t -
-x -
-z