One approach is to have the shared object implement a well known
function that is called when the object is loaded. For example, a
shared object must implement a function with the prototype,

        char **functions();

This function returns a NULL terminated array of (C-style) strings
naming the functions available in the shared object. The program
loading the shared object calls this function and stores the array
returned for future reference. The shared object implementer can use
any mechanism to build the array of strings, even just maintaining the
array by hand.

To handle parameters and different return values, the strings may be
augmented with the return and parameter types, but that is not
required to get full credit on the question.