A process can load a shared library at runtime by using the dlopen() call, which instructs the runtime linker to load this library. Once the library is loaded, the program can call any function within that library by using the dlsym() call to determine its address.
The program can also determine the symbol associated with a given address by using the dladdr() call. Finally, when the process no longer needs the shared library, it can call dlclose() to unload the library from memory.