[coreboot] why my program segmentation fault?

[Star Liu]

I wrote a program to copy the memory content of FFFF0000-FFFFFFFF to a
file, but it says "Segmentation fault", (i use AMD64 lenny, so the
address is long), how could i fix it? thanks!

#include <string.h>
#include <stdio.h>

void CopyMemoryToFile(char* FilePath, long StartAddress, long OffSet)
{
    FILE* Memory;
    Memory=fopen (FilePath, "w");
    if(Memory!=NULL)
    {
    	void* Start;
    	Start=StartAddress;
        fwrite(Start, 1, OffSet, Memory);
    }
    fclose(Memory);

}
int main (void)
{
    CopyMemoryToFile("~/cgi-bin_d/Memory",0xFFFF0000,0xFFFF);
    return 0;
}