unifdefall(1) on FreeBSD
The text 2a9b6991a0e7, as FreeBSD 6.4-RELEASE shipped it.
remove preprocessor conditionals from code
Flags it lists
-
-D -
-I -
-U -
-c -
-d -
-e -
-iD -
-iU -
-k -
-l -
-n -
-s -
-t