Entry Points

To avoid namespace collisions, you can declare your callback functions to be static. This causes their names to exist only within the scope of the file. If you do not declare these functions to be static, they will have global scope.

If you follow the convention of using static declarations for callback functions, your driver file should contain the callback function definitions and the DDA entry point; see Dynamic Data Access (DDA) Driver Initialization. You can place
C-language helper functions or C++ object definitions in separate files from the file that defines your callback functions and DDA entry point.