m4(1) on OpenBSD
The text e0892e3ae479, as OpenBSD 2.3, OpenBSD 2.2, OpenBSD 2.1 shipped it.
macro language processor
Flags it lists
-
-D -
-U
The text e0892e3ae479, as OpenBSD 2.3, OpenBSD 2.2, OpenBSD 2.1 shipped it.
macro language processor
-D
-U