Puzzle SL22

Rule 1.2c, 2.1, and 2.4

What does the following code write to the monitor?

---

/* --- fileA.c --- */
int x = 8;

---

/* --- fileB.c --- */
void foo()
{
  int x;
  x = 99;
}

---

/* --- fileC.c --- */
#include <stdio.h>
void foo();

extern int x;
void main()
{
  foo();
  printf("%d\n", x ); 
}

---

Notice that this is nearly the same as the previous puzzle except now the keyword extern is used in fileC.c.

The local variable x in foo() has no linkage.