A DWORD_PTR is an unsigned long type used for pointer precision. It is used when casting a pointer to an unsigned long type to perform pointer arithmetic. DWORD_PTR is also commonly used for general 32-bit parameters that have been extended to 64 bits in 64-bit Windows. For more information, see ULONG_PTR.
This type is declared as follows:
typedef ULONG_PTR DWORD_PTR;