This paper describes experimental work on cohabitation and cooperation between a distributed operating system (Chorus 1 ) and an event driven operating system (MacOS 2 ). Our aims were to exploit the graphical and the musical capabilities of Macintosh hardware and software directly from Chorus applications, while minimizing our efforts in the field of device drivers and hardware interfaces. The work was carried out in four major stages. The first stage was to port the Chorus kernel on the Macintosh hardware. In the second stage we changed the way Chorus managed the hardware in order to keep the MacOS system alive. Conversely, we modified slightly the way Chorus was booted so as to present it as an application to MacOS. This led us to the third stage, which was to share system events (e.g. hardware interrupts) between the two systems. The Chorus system allows one to have multiple functions connected to an interrupt. This feature was used to connect both an internal Chorus driver an...

This paper addresses the problem of cohabitation and cross-usage between a micro kernel and an event driven operating system. The aim of this work was to use the graphical power and the musical capabilities of the Macintosh hardware and software directly from Chorus active entities (called actors) with the minimum work done in the field of devices' drivers and hardware interfaces. To achieve it, we have reused the Macintosh Operating System 1 , and encapsulated it in a subsystem on top of the Chorus 2 micro kernel. The subsystem allows Chorus actors to use the MacOS operating system interface. The resulting subsystem is composed of two actors: a Supervisor actor and a Server that executes at the user level. The supervisor actor handles MacOS system calls and interrupts. For each of these interrupts or system calls, it sends a message to the server. The server is a multiplexed actor with two specialized threads handling the interrupt messages and one thread waiting for messages des...