UNIVERSITY EXAMINATIONS: 2019/2020
EXAMINATION FOR THE DEGREE OF BACHELOR OF SCIENCE IN
INFORMATION TECHNOLOGY
BIT1106A OPERATING SYSTEMS
DISTANCE LEARNING
DATE: APRIL, 2019 TIME: 2 HOURS
INSTRUCTIONS: Answer Question One & ANY OTHER TWO questions.
QUESTION ONE [30 MARKS]
a) Define an operating system (2 Marks)
b) Give SIX types of operating systems (6 Marks)
c) Give SIX functions of the operating system (6 Marks)
d) Define a shell as used in operating system (3Marks)
e) What is the function of a file manager? (3 Marks)
f) Draw the structure of the MSDOS operating system (5Marks)
b) In your opinion why is Linux operating system emerging as an Operating system to reckon
over its rival Microsoft windows (5Marks)
QUESTION TWO [20 MARKS]
a) Describe briefly the ways that can be used to terminate a process. (4 Marks)
b) What is a control structure that the operating system uses to keep the information of the
process context? Give the pieces of information that are likely to be in this structure. (4 Marks)
c) (i) What is a binary semaphore? (2 Marks)
(ii) Describe the signal and wait operation and how it is implemented in a semaphore. (4 Marks)
d) (i) Explain what a thread is? Give an example. (2 Marks)
(ii) What is the difference between a process and a thread? (4 Marks)
QUESTION THREE [20 MARKS]
a) Distinguish between the following pairs of terms:
i) Starvation and Deadlock [2Marks]
ii) Fault avoidance and Error detection [2Marks]
iii) Device driver and Device controller [2Marks]
iv) Paging and segmentation [2Marks]
b) Explain five desirable features of a process scheduling algorithm [5Marks]
c) Describe the operation of Round Robin and Multilevel Feedback Queues scheduling
algorithms. [5Marks]
d) Outline any two factors to consider in operating system design [2Marks]
QUESTION FOUR [20 MARKS]
a) With the aid of a diagram, explain the relationship between operating system, computer
hardware, utility programs and application programs [6Marks]
c) Identify two functions of the operating system. [2Marks]
d) Describe at least two operating system structures. [4Marks]
e) (i) Briefly explain four main performance criteria used to select a scheduling algorithm.
[4Marks]
(ii) Describe the four conditions for deadlock in Operating System. [4Marks]
QUESTION FIVE [20 MARKS]
(a) (i) Explain briefly the objective of computer security. (2 Marks)
(ii) State three procedure and processes that specify security policies. (3 Marks)
(i) What does data integrity entail (3 Marks)
(b) Explain briefly the following terms with respect to inter-process synchronization
(i) Critical section and (ii) Mutual exclusion (4 Marks)
(c) Describe the three forms of explicit inter-process synchronization (6 Marks)
(d) Describe two ways in which a program can invoke services of the operating system.
(2 Marks)
