The #ifdef DYNAMIC_LOADING block is long, starting on line 97 and ending at line 339. This block contains function definitions for dynamic loading. It also contains the LoadOneFunc() procedure to obtain any requested function from the dynamic library and the DynLoadDiskLib() procedure to bind it. This demonstration feature could also be called “runtime loading” to distinguish it from dynamic linking.
To try the program with runtime loading enabled on Linux, add -DDYNAMIC_LOADING after g++ in the Makefile and recompile. On Windows, define DYNAMIC_LOADING in the project.