Function winapi::um::setupapi::SetupDiGetClassDevsExA

pub unsafe extern "system" fn SetupDiGetClassDevsExA(
    ClassGuid: *const GUID, 
    Enumerator: PCSTR, 
    hwndParent: HWND, 
    Flags: DWORD, 
    DeviceInfoSet: HDEVINFO, 
    MachineName: PCSTR, 
    Reserved: PVOID
) -> HDEVINFO