A/UX
A/UX is a Unix-based operating system from Apple Computer for Macintosh computers, integrated with System 7's graphical interface and application compatibility. It is Apple's first official Unix-based operating system, launched in 1988 and discontinued in 1995 with version 3.1.1.[2] A/UX requires select 68k-based Macintosh models with an FPU and a paged memory management unit (PMMU), including the Macintosh II, SE/30, Quadra, and Centris series.[3]
Described by InfoWorld as "an open systems solution with the Macintosh at its heart",[4] A/UX is based on UNIX System V Release 2.2, with features from System V Releases 3 and 4 and BSD versions 4.2 and 4.3. It is POSIX- and System V Interface Definition (SVID)-compliant and includes TCP/IP networking since version 2. Having a Unix-compatible, POSIX-compliant operating system enabled Apple to bid for large contracts to supply computers to U.S. federal government institutes.[5][6]
Features[edit]
A/UX provides a graphical user interface including the familiar Finder windows, menus, and controls. The A/UX Finder is a customized version of the System 7 Finder, adapted to run as a Unix process and designed to interact with the underlying Unix file systems. A/UX includes the CommandShell terminal program, which offers a command-line interface to the underlying Unix system. An X Window System server application (called MacX) with a terminal program can also be used to interface with the system and run X applications alongside the Finder. Alternatively, the user can choose to run a fullscreen X11R4 session without the Finder.[4]
Apple's compatibility layer allows A/UX to run Macintosh System 7.0.1, Unix, and hybrid applications. A hybrid application uses functions from both the Macintosh toolbox and the Unix system. For example, it can run a Macintosh application which calls Unix system functions, or a Unix application which calls Macintosh Toolbox functions (such as QuickDraw), or a HyperCard stack graphical frontend for a command-line Unix application. A/UX's compatibility layer uses some existing Toolbox functions in the computer's ROM, while other function calls are translated into native Unix system calls; and it cooperatively multitasks all Macintosh apps in a single address space by using a token-passing system for their access to the Toolbox.[7]
A/UX includes a utility called Commando (similar to a tool of the same name included with Macintosh Programmer's Workshop) to assist users with entering Unix commands. Opening a Unix executable file from the Finder opens a dialog box that allows the user to choose command-line options for the program using standard controls such as radio buttons and check boxes, and display the resulting command line argument for the user before executing the command or program. This feature is intended to ease the learning curve for users new to Unix, and decrease the user's reliance on the Unix manual. A/UX has a utility that allows the user to reformat third-party SCSI drives in such a way that they can be used in other Macs of that era.[4]
A/UX requires 68k-based Macintoshes with a floating point unit (FPU) and a paged memory management unit (PMMU),[8] and select models. For example, the Quadra 840AV, the fastest 68k Macintosh, cannot run A/UX.[9]