1. When a process moves from running to idle, the state of the machine has to be saved. Obviously this cannot mean the whole state, as there would be no place to save it. Just what information has to be saved?

2. There are two different implementations of POSIX pthreads in Linux. One is at user level, the other is as kernel threads. Which one is installed on the system you are using?

3. Some operating systems create a new process as a clone of the existing one; others create a new process with a new program. Discuss the advantages and disadvantages of both systems.

4. Investigate the different versions of the exec() system service, and istinguish between them.

5. Investigate how to pass parameters to a thread, when creating it.

6. Modern CPUs have special instructions to do all of the copying of registers required at a context switch. Investigate this instruction for a machine of your choice.