_PS_STD_HANDLE_STATE

Windows 8.1 | Server 2012R2 Update 1
Windows 10 1507 (Original Release, Threshold 1)
Windows 10 1511 (November Update, Threshold 2)
//0x4 bytes (sizeof)
enum _PS_STD_HANDLE_STATE
{
    PsNeverDuplicate = 0,
    PsRequestDuplicate = 1,
    PsAlwaysDuplicate = 2,
    PsMaxStdHandleStates = 3
};