A Neutral Look at Operating Systems/AmigaOS

AmigaOS is the default native operating system of the Amiga personal computer. On top of a basic kernel called Exec, it includes an abstraction of the Amiga's unique hardware, a disk operating system called AmigaDOS, a windowing system called Intuition and a graphical user interface called Workbench.

The 1.x versions are the original implementation of AmigaOS. They defaulted to a distinctive blue and orange colour scheme which was designed to give high contrast on even the worst of television screens (it could easily be changed by the user). Versions 1.1 consisted mostly of bug fixes. Versions 1.0 and 1.1 were distributed only on floppy disks for the Amiga 1000.

Version 1.2 was the first to have Kickstart on a ROM and Workbench on one or two floppy disks. Workbench was then booted from floppy disk or installed on a hard disk on later machines. The early Kickstarts were still available on floppies for Amiga 1000 owners. These versions were shipped in ROM with the A500, A1500, CDTV (1.3 only) and A2000. Version 1.2 of Kickstart fixed many bugs, greatly improving the stability of the system, and added AutoConfig support which could automatically configure expansion boards. Release 1.3 had few changes to Kickstart (mainly to enable autobooting hard disks) but had many improvements in Workbench, including a much faster file system for hard disks, an improved CLI, and various extra programs.

Kickstart/Workbench 1.4 was a beta version of the upcoming 2.0 update and never released, but the Kickstart part was shipped in very small quantities with early Amiga 3000 computers, where it is often referred to as the "Superkickstart ROM". In these machines it is only used to bootstrap the machine and load the Kickstart that will be used to actually boot the system. The appearance is similar to that of 2.0 and higher, with just minor differences. It is, however, possible to dump out of the OS selection screen by clicking where one would expect to see a close gadget. This will cause the machine to boot Kickstart 1.4 using either the wb_2.x: partition, or from a floppy.

Kickstart/Workbench 2.0 introduced a lot of major advances to the Amiga operating system. Gone was the harsh blue and orange colourscheme, replaced with a much easier on the eye grey and light blue. The Workbench was no longer tied to the 640×256 (PAL) or 640×200 (NTSC) display modes, and much of the system was improved with an eye to making future expansion easier. For the first time, a standardised "look and feel" was added. This was done by creating the Amiga Style Guide, and including libraries and software which assisted developers in making conformant software. Technologies included the GUI element creation library gadtools, the software installation scripting language Installer, and the AmigaGuide hypertext help system.

3.x was another major update. Updates included:

• A universal data system, known as datatypes, that allowed programs to load pictures, sound and text in formats they didn't understand directly, through the use of standard plugs (see object-oriented operating system)
• A system-standard localization system, allowing the user to make an ordered list of preferred languages; when a locale-aware application runs, it asks the operating system to find the catalog (a file containing translations of the application's string) best matching the user's preferences
• Colour remapping for low-colour display modes
• Improved visual appearance
• Better support for background images

Along with this update came a change in the way people referred to the Amiga's operating system. Rather than specifying "Kickstart" or "Workbench", the updates were most often referred to as simply "AmigaOS".

Updates included:

• CD filesystem support as standard
• Distribution on CD instead of floppy disk
• Supplied with TCP/IP stack, web browser, and e-mail client
• Improved GUI, called "ReAction"
• AVI/MPEG movie player (OS3.9)
• Support for hard disks larger than 4Gb (a limitation from 1.x)
• HTML documentation
• MP3 and CD audio player (OS3.9)
• Dock program (OS3.9)
• Improved Workbench
• Find utility (OS3.9)
• ASync workbench (no more waiting for files to be copied)

AROS Research Operating System is an attempt to clone the AmigaOS API in a portable open-source operating system. Although not binary compatible with AmigaOS (unless running on 68k), users have reported it to be highly source code compatible.

See AROS wikibook.

A new version of AmigaOS is being developed by Hyperion Entertainment under license from Amiga, Inc. The 4.0 version will be a major update a decade after the last official release.

Main features planned for AmigaOS 4.0:

• Tripos legacy code finally removed
• Improved TCP/IP networking
• Fully skinnable GUI
• Virtual memory
• Limited memory protection
• CD/DVD writer support, including Mt. Rainier
• Integrated debugger
• Integrated viewer for PDF and other document formats
• Enhanced shared library model
• Support for PowerPC (native) and 68k (emulated JIT) applications
• Improved input device support
• Support for modern hardware devices
• New USB stack
• New PCI stack
• New interface module (replaces the jump table of classic AmigaOS)
• Stack enlargement
• Resource tracking
• Faster memory allocation system, similar to what’s used on Solaris
• 2 GB file limit removed
• New version of AmiDock with plug in support
• New CDFilesystem with Joliet and HFS support, DVDRW support
• HDToolbox replacement
• New HD Recovery tool
• Added support for Truetype and Postscript fonts, with optional anti-aliasing
• Integrated Picasso 96 2D Graphics API
• Integrated Warp3D 3D Graphics API
• Integrated AHI Sound API

MorphOS is a PowerPC native operating system, originally created when the future of the Amiga looked uncertain. It provides binary compatibility with system-friendly AmigaOS applications. A version which runs on Classic Amigas with PPC accelerator cards has been released.

MorphOS is a mixed proprietary and open source operating system produced for the Pegasos, Efika, Mac and AmigaOne hardware platforms by a core development team and contributors. The OS itself is proprietary. Several libraries and other parts are open source, such as Ambient (the desktop interface).

It currently runs only on PowerPC processors by Freescale and IBM while still supporting the original AmigaOS MC680x0 applications via its proprietary task-based emulation solution and most of the newer, PPC/AmigaOS applications using API wrappers. It is API-compatible with AmigaOS 3.1 but implements many enhancements that bring it up to date, and a modern GUI based on MUI.