Exercises

   


14.1 What is the purpose of the boot program?

14.2 What is the job of the assembly-language startup? Why is this program written in assembly language?

14.3 What processes are started when the system is booted?

14.4 How are kernel modules loaded into the system at boot time? Give an example of a kernel module.

14.5 The reboot system call causes the system to halt or reboot. Give two reasons why this system call is useful.

14.6 Give two reasons why kernel-loadable modules are useful in developing kernel services. Give one reason not to use them.

14.7 Why is it necessary to have a particular order in which the kernel services are loaded and initialized? Why is it also necessary to have a particular order in which kernel services are shut down?

*14.8 Suppose that a machine does not have a battery-backup time-of-day clock. Propose a method for determining that the time-of-day clock is incorrect. Describe a way to initialize the clock's time of day. What are the limitations of your method?

**14.9 What are the necessary macros to create a kernel-loadable module? How would you test your module without linking it directly into the kernel?


   
 


The Design and Implementation of the FreeBSD Operating System
The Design and Implementation of the FreeBSD Operating System
ISBN: 0201702452
EAN: 2147483647
Year: 2003
Pages: 183

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