The LARGE_INTEGER structure is used to represent a 64-bit signed integer value.
typedef union _LARGE_INTEGER {
struct {
DWORD LowPart;
LONG HighPart;
};
LONGLONG QuadPart;
} LARGE_INTEGER;
The LARGE_INTEGER structure is actually a union. If your compiler has built-in support for 64-bit integers, use the QuadPart member to store the 64-bit integer. Otherwise, use the LowPart and HighPart members to store the 64-bit integer.