Functions exported and imported by a dynamic link library are identified in the library module definition file. These provide links between libraries and subsystems. For example, the components of the Presentation Manager interface must call an enable entry point in the presentation driver. The presentation driver needs access to the simulated functions in the graphics engine. For information on how to develop a dynamic link library (DLL), refer to the OS/2 Programming Guide and OS/2 Application Design Guide.

Note: The initialization routine for a dynamic link library, including presentation drivers, must be compiled to run at Ring 3 (privilege level 3).