One most important charateristic of rtker, which makes it different from other Real Time Operating Systems is the way in which the thread library has been implemented. As we have explained earlier, the scheduling algorithm, used by the thread library is not defind by the kernel but by the user defined scheduler object. The job of the kernel thread library is only restricted to allocating space for thread control blocks, time slicing between threads, providing synchronization between threads and updating the scheduler object through proper function calls. The kernel does not keep any information regarding the ready queue (threads which are ready), blocked threads etc. All this bookkeeping of is the job of the user defined scheduler object9.1.
In this chapter we broadly outline the implementation of the thread library.
Please refer to the source code comments for details. The chapter is organized
as follows. In section 1 we have described the structure of the thread control
block . In the next section we have briefly described the functions of the
thread library.