A2 (formerly named Active Object System (AOS), and then Bluebottle) is a modular, object-oriented operating system with features including automatic garbage-collected memory management, and a

zooming user interface In computing, a zooming user interface or zoomable user interface (ZUI, pronounced zoo-ee) is a type of graphical user interface (GUI) where users can change the scale of the viewed area in order to see more detail or less, and browse through ...

. It was developed originally at

ETH Zurich ETH Zurich (; ) is a public university in Zurich, Switzerland. Founded in 1854 with the stated mission to educate engineers and scientists, the university focuses primarily on science, technology, engineering, and mathematics. ETH Zurich ran ...

in 2002. It is

free and open-source software Free and open-source software (FOSS) is software available under a license that grants users the right to use, modify, and distribute the software modified or not to everyone free of charge. FOSS is an inclusive umbrella term encompassing free ...

under a BSD-like license.

History

A2 is a successor to Native Oberon, the

x86 x86 (also known as 80x86 or the 8086 family) is a family of complex instruction set computer (CISC) instruction set architectures initially developed by Intel, based on the 8086 microprocessor and its 8-bit-external-bus variant, the 8088. Th ...

PC version of

Niklaus Wirth Niklaus Emil Wirth ( IPA: ) (15 February 1934 – 1 January 2024) was a Swiss computer scientist. He designed several programming languages, including Pascal, and pioneered several classic topics in software engineering. In 1984, he won the Tu ...

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

Oberon Oberon () is a king of the fairy, fairies in Middle Ages, medieval and Renaissance literature. He is best known as a character in William Shakespeare's play ''A Midsummer Night's Dream'', in which he is King of the Fairies and spouse of Titania ...

. Out of print
Electronic reprint.
/ref> It supports

multiprocessing Multiprocessing (MP) is the use of two or more central processing units (CPUs) within a single computer system. The term also refers to the ability of a system to support more than one processor or the ability to allocate tasks between them. The ...

computers, and provides soft

real-time computing Real-time computing (RTC) is the computer science term for Computer hardware, hardware and software systems subject to a "real-time constraint", for example from Event (synchronization primitive), event to Event (computing), system response. Rea ...

operation. It is entirely written in Active Oberon.

User interface

Bluebottle replaced the older Oberon OS's unique

text-based user interface In computing, text-based user interfaces (TUI) (alternately terminal user interfaces, to reflect a dependence upon the properties of computer terminals and not just text), is a retronym describing a type of user interface (UI) common as an ear ...

(TUI) with a

(ZUI), which similar to a conventional

graphical user interface A graphical user interface, or GUI, is a form of user interface that allows user (computing), users to human–computer interaction, interact with electronic devices through Graphics, graphical icon (computing), icons and visual indicators such ...

(GUI). Like Oberon, though, its user interface supports a ''

point and click Point and click are one of the actions of a computer user moving a pointer to a certain location on a screen (''pointing'') and then pressing a button on a mouse or other pointing device (''click''). An example of point and click is in hypermed ...

'' interface metaphor to execute commands directly from text, similar to clicking

hyperlink In computing, a hyperlink, or simply a link, is a digital reference providing direct access to Data (computing), data by a user (computing), user's point and click, clicking or touchscreen, tapping. A hyperlink points to a whole document or to ...

s in a

web browser A web browser, often shortened to browser, is an application for accessing websites. When a user requests a web page from a particular website, the browser retrieves its files from a web server and then displays the page on the user's scr ...

Features

A2's design allows developing efficient systems based on ''active objects'' which run directly on hardware, with no mediating interpreter or

virtual machine In computing, a virtual machine (VM) is the virtualization or emulator, emulation of a computer system. Virtual machines are based on computer architectures and provide the functionality of a physical computer. Their implementations may involve ...

. Active objects represent a combination of the traditional

object-oriented programming Object-oriented programming (OOP) is a programming paradigm based on the concept of '' objects''. Objects can contain data (called fields, attributes or properties) and have actions they can perform (called procedures or methods and impl ...

(OOP) model of an object, combined with a thread that executes in the context of that object. In the Active Oberon implementation, an active object may include activity of its own, and of its ancestor objects. Oberon A2Desktop Screen

A2 incorporates a minimalist design, implemented in a type-safe language with automatic memory management, combined with a set of primitives (at the level of

programming language A programming language is a system of notation for writing computer programs. Programming languages are described in terms of their Syntax (programming languages), syntax (form) and semantics (computer science), semantics (meaning), usually def ...

and

runtime system In computer programming, a runtime system or runtime environment is a sub-system that exists in the computer where a program is created, as well as in the computers where the program is intended to be run. The name comes from the compile time ...

) for synchronizing access to the internal properties of objects in competing

execution Capital punishment, also known as the death penalty and formerly called judicial homicide, is the state-sanctioned killing of a person as punishment for actual or supposed misconduct. The sentence ordering that an offender be punished in ...

contexts. Above the kernel layer, A2 provides a set of modules providing unified abstractions for devices and services, such as file systems,

user interface In the industrial design field of human–computer interaction, a user interface (UI) is the space where interactions between humans and machines occur. The goal of this interaction is to allow effective operation and control of the machine fro ...

computer network A computer network is a collection of communicating computers and other devices, such as printers and smart phones. In order to communicate, the computers and devices must be connected by wired media like copper cables, optical fibers, or b ...

connections, media

codec A codec is a computer hardware or software component that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder o ...

s, etc.

References

External links

Main Project Page

A2 Operating System & Active Oberon community in Telegram

An application in industrial control at Radiar

A2 user guide and applications description

A short movie showing a programming technique and the Bluebottle OS
* Archived , ETH Zürich * Archive
Oberon Language Genealogy
* Archive
Oberon Community Platform - Wiki & Forum
{{Wirth Free software operating systems ARM operating systems IA-32 operating systems X86-64 operating systems

History

User interface

Features

See also

References

External links