I have seen so many people say that Amiga OS is Unix like or similar. Amiga OS is not like any other OS (Other than newer versions of Amiga OS and clones of Amiga OS), not even TripOS (from which the disk I/O, file routines, and command line come for the Amiga OS). Amiga OS is a unique Message Passing Microkernel based Preemptive Multitasking OS with a Windowing System that is more capable in some ways than anything we have today.

For Amiga OS there was no such thing as protected memory, and multitasking was way better than Unix given similar CPU. The library management was something unique to the Amiga, no run time linking required (and this is the source of the ongoing HUNK versus ELF debate of newer Amiga and Amiga clone Operating Systems), instead of linking the application uses negative offsets relative to the library base (and the base of Exec is always 4 on 680x0 systems). In Amgia OS all system calls are Library calls of some form (no exceptions for using software interrupts for some things like n*x).

Intuition (the graphical Window Manager) was so far ahead that no mainstream Windowing System has caught up even today. It had some compositing like features, it was a consistent user interface, though that is about as far as it is comparable. It also was its own task, calling directly into applications in a signal like way to report user events (thus even a 'zombie task' could still have a responsive UI). It also had a cool means of handling applications running on there own screens, with the ability to have many simultaneous full screen applications at the same time (and even have part of multiple on screen at once divided vertically), or even windows on other screens. And all that is from the start, it would get even better with the coming of Amiga OS 2.

Amiga OS 2 brought some technical improvements, a better DOS (disk, filesystem, CLI stuff), the appearance of windows and widgets was improved as well. The big two points of Amiga OS 2 were BOOPSI and GadTools. BOOPSI (Basic Object Oriented Programming System for Intuition) was an Object Oriented extension for Intuition (that works well without an OO language), that added the ability for gadgets (and other GUI Objects) to call each other, making the UI even more responsive even if the task to which it belongs is a Zombie at the time. GadTools is a set of gadgets (buttons, scroll bars, cyclers, etc) that uses BOOPSI, and was miles ahead of anything on any other computer, even today (modern OO needs an OO language to use with ease, on modern windowing systems a zombie task will not respond in any way to events).

On the DOS of Amiga OS 2: It is only breezed by above, as it started out as an addition library for Amiga OS 1.x known as ARP.LIBRARY (AmigaDOS Replacement Project Library). It was a huge improvement over the base DOS (that came from TripOS), and is thus a worthy upgrade, though it was around long before Amiga OS 2. This DOS library provided a more standard Amiga C Library Calling convention to the DOS (originally all of Amiga OS was C calling convention, except AmigaDOS which was BCPL convention). There were other improvements with versions of ARP.LIBRARY, and would continue to be even after Amiga OS 2.x, and even after Amiga OS 3.1 for that matter (the last Commodore version of Amiga OS).

The native filesystems of Amiga OS store the date with a separate 32-bit field for the number of days since Jan 1st 1978. This if taken to be a signed number means that the date will not roll over for at least 5.8 Million Years, if taken to be unsigned much longer (and as far as I know the Amiga treats it as unsigned). As such there is less chance of us as a species ever seeing the roll over for Amiga dates.

I hope that this little rant may just get some people to better understand what Amiga OS really is. Perhaps even inspire someone to try Amiga OS (or one of its clones) for the first time. This is an OS that will never die, it is and has always been way ahead of the pack, in at least a few areas.

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