The Get Device/Volume Information routine provides a simplified
    interface to the $GETDVI system service. It returns information
    about the primary and secondary device characteristics of an I/O
    device. The calling process need not have a channel assigned to
    the device about which it wants information.

    Format

      LIB$GETDVI  item-code [,channel] [,device-name]

                  [,longword-integer-value] [,resultant-string]

                  [,resultant-length] [,pathname]