// PtrToDouble.cpp : Implementation of CPtrToDouble
#include "stdafx.h"
#include "A4.h"
#include "PtrToDouble.h"
#include <iostream>
using namespace std;

/////////////////////////////////////////////////////////////////////////////
// CPtrToDouble


STDMETHODIMP CPtrToDouble::myFunction(DOUBLE *pDouble)
{
	cout << "\n\nInside myFunction:"
       << "\n  value passed in = " << (*pDouble);

  *pDouble = (*pDouble) * (*pDouble);
  cout << "\n  squared value of input = " << *pDouble;
  cout << "\n  address of double variable = " << pDouble << endl;

  // The next statement doesn't make sense.  I've put this here
  // simply to demonstrate that while we can change the memory 
  // location pointed to inside this function, we can't change the 
  // memory pointed to by pDouble outside this function.  To do 
  // that we would need to use another level of indirection, e.g.,
  // DOUBLE **ppDouble.

  pDouble = (DOUBLE*)CoTaskMemAlloc(sizeof(DOUBLE));
  *pDouble = 0.33333;
  cout << "\n  changing location pointed to in component "
       << "\n  won't change location pointed to in client"
       << "\n  new address of double variable = " << pDouble
       << "\nLeaving myFunction:" << endl;

	return S_OK;
}