~4Dgifts/toolbox/src/swtools/DSO README The following example demonstrates the use of dynamic shared objects (DSO). A DSO is loaded into a program by opening it with dlopen(3X). At this point, all functions in a DSO are available to the program. The dlsym(3X) routine will return the address of the desired function. When the program is finished with a particular DSO, it should unload it by calling the dlclose(3X) routine. When a DSO is loaded into a program, the whole shared object is located somewhere in the program's address space. This means all the functions within the DSO (whether used or not) will take up space in memory. To free up some program virtual address space, a DSO should be unloaded once it is no longer needed.
Source
Documentation
Reference