/*! \file       pass-by-value.c 

    \brief      Small example that illustrates the fact that
                C passes its parameters by value instead of by
                reference.
                
                Although x is modified in the function foo, the
                main function does not see that modification after
                the call to foo().
    
    \author     Michelle Strout
    \date       October 2008
*/

#include <stdio.h>

void foo(int x) { 
  printf("foo: x = %d\n", x);
  x = 45; 
  printf("foo: x = %d\n", x);
}

int main()
{
  int x = 21;
  printf("x = %d\n", x);
  foo(x);
  printf("x = %d\n", x);
  return 0;
}