facing segfault in c program

Question

Possible Duplicate:
Pointer-array-extern question

We have two files:

file1.c

int myarray[10];

file2.c

extern int *myarray;

void foo()
{
    myarray[0]=10;
}

void main() 
{
    foo();
}

This program gives a segmentation fault. However If we change the extern int *myarray to extern int myarray[] , the program works.

Please explain. Thanks!