Graphics-Based Operating Systems: The New Alternative to Traditional Operating Systems and Top-Down Programming

Abstract

My work at I/NET Inc. this past term dealt with introducing the OS/2 Presentation Manager environment to a company that had previous experience in MS-DOS and Microsoft Windows on IBM PCs. The OS/2 Presentation Manager is the new operating system introduced jointly by IBM and Microsoft in 1987 as the official replacement for the aging MS-DOS (the operating system that has powered IBM PCs and compatibles since 1981). The operating system kernel has borrowed many features from UNIX and has enhanced many other features to make them more modern. The Presentation Manager is the graphical user interface that sits on top of the kernel and provides the functionality of the user interface. The Presentation Manager is a grown-up version of Microsoft Windows that includes a powerful graphics library based on existing IBM mainframe packages. This environment is designed around the IBM Systems Application Architecture (SAA) that IBM is making standard on its entire line of computers. Also, Open Software Foundation (OSF) has adopted the look and feel of the Presentation Manager as its standard for UNIX graphical workstations. Before I started working for I/NET, I had little experience programming in a graphical environment. My experience was limited to several books on the subject. This paper is meant to help others understand some of the obstacles that a graphics-based operating system can place in front of someone who only has knowledge of programming in top-down programming languages in traditional environments. The discussion explains the basics of a graphics-based operating system and also points out the major differences between programming in environments most all programmers are accustomed to and programming in one of these future-style environments.