Access function variable values without arguments

I am with a problem which consists in print some value of a function(FOO) with another function(RECOVER), but recover is a void function without arguments. How could I access the foo variables ?

Example:

int foo(int a, short b, char c){
   int x, y, z;
   x = a;
   y = b;
   z = c;
   recover();
}

void recover()
{
    How can I print the x y z values here ?
}

PS: I can create another function that would help me to do it. Could I access these values using the register values ? Or pointers ?

Thank you guys