The Initialization of the ChorusOS Microkernel and OS

The ChorusOS operating system boots from the system image. The system image contains binary executable files of the bootstrap program, debug agent, microkernel, drivers, OS servers and applications. It can also contain a set of data files such as networking configuration files.

System image files are organized in one or more memory banks. Each memory bank can be formatted as a file system volume (for example, FAT12) and exported through the microkernel API as a memory device. Thus a system image file can be viewed as a file in a file system volume on a memory device.

The ChorusOS operating system is initialized in two stages:

1. microkernel initialization

2. OS service initialization

The microkernel is the minimal ChorusOS operating system comprising the microkernel and the built-in drivers. The bootstrap program starts the microkernel. The microkernel then starts the built-in drivers.

The operating system (OS) is implemented on top of the microkernel as a set of actors that provide services such as file systems and networking protocols. ChorusOS actors are defined and detailed in "Using Actors" in ChorusOS 5.0 Application Developer's Guide.

The microkernel starts the OS services by creating the initial subset of OS actors from the system image binary files. The OS can then activate additional system services by loading actors from files located on the system image memory, or from local or remote devices.