Differentiating between USB flash drive and USB hard drive on Windows

Question

I'm trying to differentiate between a USB flash drive and a USB hard drive on Windows using the Win32 API.

The GetDriveType() function will return DRIVE_REMOVABLE if the drive is removable, and USB flash drives are of course removable. But I'm thinking that Windows probably considers USB hard drives removable as well (unfortunately I don't have access to a USB hard drive to test it out).

Thanks in advance.

Answer 1

If you want to determine that a device is USB device, you can open its handle and send IOCTL queries using DeviceIoControl() to get bus type a device is connected to.

EnumUsbDrivesLetters - the post is in Russian but it contains C++ source code, so the matter could be understood easily.

Cheers, Andriy

Answer 2

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//  Method      OpenVolume
//  Purpose:    Open volume for removal. Change to ::CreateFile(volumeName, 0, 0, 0, OPEN_EXISTING, FILE_FLAG_NO_BUFFERING, 0);
//              if you just want to inquire if it's removable. 
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////

HANDLE OpenVolume(const char& driveLetter)
{
    char volumeName[8] = "";
    char* volumeFormat = "\\\\.\\%c:";
    sprintf(volumeName, volumeFormat, driveLetter);

    HANDLE volume = ::CreateFile(volumeName, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL);
    if (volume == INVALID_HANDLE_VALUE) return INVALID_HANDLE_VALUE;

    DWORD bytesReturned = 0;
    STORAGE_HOTPLUG_INFO Info = {0};
    if (::DeviceIoControl(volume, IOCTL_STORAGE_GET_HOTPLUG_INFO, 0, 0, &Info, sizeof(Info), &bytesReturned, NULL)) 
    {
        if (!(Info.MediaRemovable || Info.DeviceHotplug)) 
        {
            ::CloseHandle(volume);
            ::SetLastError(ERROR_INVALID_PARAMETER);
            return INVALID_HANDLE_VALUE;
        }
    }

    return volume;
}