OPENSTEP 4.2  Copyright1997 by Apple Computer, Inc.  All Rights Reserved.

OPENSTEP 4.2 Release Notes: 
Driver Development

OPENSTEP 4.2 cannot be used to develop Mach device drivers. Because NEXTSTEP 3.3 device drivers work on OPENSTEP 4.2 systems, we recommend that you use NEXTSTEP 3.3 Developer to create device drivers.