C++ How to Program, 10/e

... function3
16   void function2() {
17      cout << "function3 is called inside function2" << endl;
18      function3(); // stack unwinding occurs, return control to function1
19    }
20
21   // function1 invokes function2
22   void function1() {
23      cout << "function2 is called inside function1" << endl;
24      function2(); // stack unwinding occurs, return control to main
25    }
26   
27   // demonstrate stack unwinding
28   int main() {
29      // invoke function1
30      try {
31      cout << "function1 is called inside main" << endl;
32      function1(); // call function1 which throws runtime_error
33    }
34    catch (const runtime_error& error) { // handle runtime error
35       cout << "Exception occurred: " << error.what() << endl;
36       cout << "Exception handled in main" << endl;
37    }
38   }

 function1 ...