INT 67h,  52h  GET/SET HANDLE ATTRIBUTES                             . 4.0

On entry:
        AH = 52h
        AL = subfunction
            00h get handle attributes
            01h set handle attributes
               BL = new attribute (see returned AL)
            02h get attribute capability
        DX = handle

Return:
        AL = attribute (for subfunction 00h)
            00h handle is volatile
            01h handle is nonvolatile
        AL = attribute capability (for subfunction 02h)
            00h only volatile handles supported
            01h both volatile and non-volatile supported
        AH = status
            00h successful
            80h internal error
            81h hardware malfunction
            83h invalid handle
            84h undefined function requested
            8Fh undefined subfunction
            90h undefined attribute type
            91h feature not supported