ABSTRACT
This chapter provides a description of existing open-source operating systems (OSs) which have been analyzed with the objective of providing a porting for the reference architecture. Among the various projects implementing the hardware abstraction approach, Xenomai is the one which supports the highest number of embedded architectures. The market of embedded real-time operating systems (RTOS) has been exploited in the past decades by several companies that have been able to build solid businesses. The chapter describes the state of the art of the real-time support for the Linux OS and as well for small RTOSes. Contiki is an Open-Source OS for networked, memory-constrained systems with a particular focus on low-power Internet of things devices. Ecos is an Open-Source RTOS for applications which need only one process with multiple threads. The run-time system is a fundamental software component of the parallel programming model to transform the parallel expressions defined by the user into threads that execute in the different processing units.
