Windows NT defines a LARGE_INTEGER data type that is a 64-bit integer created from an array of two longwords. A LARGE_INTEGER type is not the same as a quadword. The quadword is a true, nonportable, 64-bit integer data type; the Windows NT LARGE_INTEGER is a data type that is 8 bytes in size and is usable as a 64-bit integer only in conjunction with a set of run-time library functions. You should not redefine the LARGE_INTEGER type.