Pass by reference through multiple functions

Question

Hey all. I'm working on a project for school where I need to pass a few parameters by reference through multiple functions. I understand how I can pass by reference from where the variables are declared to another function, like this:

main() {
  int x = 0;
  int y = 0;
  int z = 0;

  foo_function(&x, &y, &z);
}

int foo_function(int* x, int* y, int* z) {
  *x = *y * *z;
  return 0;
}

However, how would I pass x, y, and z from foo function to another function? Something like this gives me all kinds of compiler warnings.

int foo_function(int* x,  int* y, int* z) {
  *x = *y * *z;
  bar(&x, &y, &z);
  return 0;
}

int bar(int* x, int* y, int* z) {
  //some stuff
}

Answer 1

Just use:

bar(x, y, z);

X, Y, and Z are already pointers - just pass them directly.

Remember - a pointer is a location in memory. The location doesn't change. When you dereference the pointer (using *x = ...), you are setting the value at that location. But when you pass it into a function, you are just passing the location in memory. You can pass that same location into another function, and it works fine.

Answer 2

You don't need to do anything, they're already references.

int foo_function(int* x,  int* y, int* z) {
  bar(x, y, z);
  return 0;
}

int bar(int* x, int* y, int* z) {
  //some stuff
}