subroutine and Functions

Is there a difference between a subroutine and a function in C++?

Not really. A subroutine just doesn't return anything (void return type).

Code:

---

void mysub(int a) // Void function (sub)
{
  cout<<a<<endl;
}

int myfunc(int a) // Function returns something
{
  return a + 5;
}

---

Can you call a subroutine?

Yeah, look at this example code.

Code:

---

#include <iostream>
using namespace std;

// Function prototype
void mysub(int);
int myfunc(int);

int main()
{
        int a, b;

        cout<<"Enter a number:"<<endl;
        cin>>a;

        mysub(a); // Prints the value of a

        b = myfunc(a); // Value of b is now 5 more than the value of a

        return 0;
}

// Actual function code
void mysub(int a) // Void function (sub)
{
        cout<<a<<endl;
}

int myfunc(int a) // Function returns something
{
        return a + 5;
}

---

Thanks for that input Wynd. :)

Also, just a terminology thing: there are no subs in C++. Everything is called functions (or methods for classes). :)

In objective-C you call them messages :p
Anyways the procedures you call functions in a functional programming language and methods in a object oriented programming language :)