where api_version is 0 to indicate old-style or 1 to indicate new-style
calling convention. In future releases, additional fields may be defined
after api_version, but these additional fields will only be used if
-api_version is greater than 2.
+api_version is greater than 1.
These details will be hidden from the author of a dynamically loaded
function by using a macro. To define a new-style dynamically loaded