sub GuidToString
{
        return sprintf "%08X-%04X-%04X-%02X%02X-%02X%02X%02X%02X%02X%02X",
                unpack("I", $_[0]),
                unpack("S", substr($_[0], 4, 2)),
                unpack("S", substr($_[0], 6, 2)),
                unpack("C", substr($_[0], 8, 1)),
                unpack("C", substr($_[0], 9, 1)),
                unpack("C", substr($_[0], 10, 1)),
                unpack("C", substr($_[0], 11, 1)),
                unpack("C", substr($_[0], 12, 1)),
                unpack("C", substr($_[0], 13, 1)),
                unpack("C", substr($_[0], 14, 1)),
                unpack("C", substr($_[0], 15, 1));
}