gistfile1.txt

void PrintDevType(HANDLE hFile)
{
	IO_STATUS_BLOCK iosb;
	FILE_FS_DEVICE_INFORMATION ffdi;
	if (0 <= NtQueryVolumeInformationFile(hFile, &iosb, &ffdi, sizeof(ffdi), FileFsDeviceInformation))
	{
		DbgPrint("%x %x\n", ffdi.DeviceType, GetFileType(hFile));
	}
}

void PrintDevType(PCWSTR pszFile)
{
	HANDLE hFile;
	IO_STATUS_BLOCK iosb;
	UNICODE_STRING ObjectName;
	OBJECT_ATTRIBUTES oa = { sizeof(oa), 0, &ObjectName, OBJ_CASE_INSENSITIVE };
	RtlInitUnicodeString(&ObjectName, pszFile);
	if (0 <= NtOpenFile(&hFile, FILE_READ_ATTRIBUTES, &oa, &iosb, 0, 0))
	{
		PrintDevType(hFile);
		NtClose(hFile);
	}
}


	PrintDevType(L"\\Device\\Null");
	PrintDevType(GetStdHandle(STD_OUTPUT_HANDLE));