#include <iostream>
#include <string.h>  // strcmp
#include <cstdlib>   // exit
#include <unistd.h>  // _exit

using namespace std;

int ExitFlag  = 0;

class testClass {
   public:
    ~testClass() {
       cout << "An instance of testClass was destroyed " << endl;
    }
};

void fun1(void) {
   cout << "Function 1 is being called " << endl;
   ExitFlag = 4;
   return;
}

void fun2(void) {
   cout << "Function 2 is being called " << endl;
   ExitFlag = 5;
   return;
}


void OnExitFunction(int exitStatus, void * arg) {
    static int calls = 0;

    calls++;

    cout << "In the OnExitFunction" << endl;
    cout << "I was called " << calls << " times "<< endl;
    cout << "The exit status was " << exitStatus << endl;
    cout << "And Exit flag is set to " << *((int *) arg) << endl;
    cout << endl;
    return;
}

int main(int argc , char * argv[]) {

    testClass a;

    on_exit(OnExitFunction,&ExitFlag);
    atexit(fun1);
    atexit(fun2);
    on_exit(OnExitFunction,&ExitFlag);
    

    cout << "In the main routine " << endl;
    cout << endl;

    if (argc == 2 and !strcmp(argv[1],"return")) {
        cout << "Calling return 0" << endl;
        cout << endl;
        return 0;
    } else if (argc == 2 and  !strcmp(argv[1],"exit")) {
        cout << "Calling exit(0)" << endl;
        cout << endl;
	exit(0);
    } else if (argc == 2 and  !strcmp(argv[1],"_exit")) {
        cout << "Calling _exit(0)" << endl;
        cout << endl;
	_exit(0);
    } else if (argc == 2 and  !strcmp(argv[1],"abort")) {
        cout << "Calling abort" << endl;
	abort();
    }

    cout << "Falling off the end "<< endl;
}