UNIVERSITY EXAMINATIONS: 2018/2019
EXAMINATION FOR THE DIPLOMA IN INFORMATION
TECHNOLOGY
DIT301 OPERATING SYSTEMS
DATE: NOVERMBER, 2018 TIME: 2 HOURS
INSTRUCTIONS: Answer question ONE and any other TWO questions.
QUESTION ONE COMPULSORY (30 MARKS)
a) Computer software can be classified into THREE categories. State and explain them giving
an example of each. [9 Marks]
b) Explain the objectives of an operating system. [5 Marks]
c) Briefly explain the following types of operating systems: [5 Marks]
i. Multi-user operating system
ii. Multi-processor and Multitasking operating system
iii. Network operating systems
iv. Real time operating systems
v. Time sharing operating systems
d) Allan wants to purchase an operating system for his new laptop. Help him identify factors
to consider when selecting the software. [5 Marks]
e) Deadlock prevention is accomplished by preventing any of the Coffman conditions from
occurring. Briefly explain how the four conditions can be prevented. [4 Marks]
f) List down FOUR examples of operating systems in the market today, [2 Marks]
QUESTION TWO
a) Explain THREE advantages and TWO disadvantages of a GUI. [5 Marks]
b) As a process executes it changes state. Explain the FIVE states that a process can have at
any given time. [5 Marks]
c) A Process Control Block contains many pieces of information associated with a specific
process. State and explain FIVE information types of a PCB. [5 Marks]
d) Define the following terms: [5 Marks]
i. Pre-emptive scheduler
ii. Non-pre-emptive scheduler
iii. Response time
iv. Turn-around time
v. Through put
QUESTION THREE
a) State and explain FIVE features of a good scheduling algorithm. [5 Marks]
b) With the aid of well labeled diagrams explain PAGING and SWAPPING memory
management techniques. [6 Marks]
c) Input or output devices differ in a number of ways state any FIVE. [5 Marks]
d) Define the following input/output terminologies: [4 Marks]
i. Spooling
ii. Buffer
iii. Polling
iv. Interrupt Mode
QUESTION FOUR
a) Describe four file management activities supported by an operating system [4 Marks
b) Describe any FOUR process scheduling techniques [8 Marks]
c) Explain the following terms as used in operating systems:-
i. Process
ii. Thread [2 Marks]
iii. External fragmentation [2 Marks]
iv. Kernel [2 Marks]
QUESTION FIVE
a) List and explain four conditions necessary for a deadlock to occur [8 Marks]
b) Briefly explain five functions of a computer operating system [5 Marks]
c) Outline TWO benefits and TWO disadvantages of Command Driven Interfaces.
[4 Marks
d) Define the term Operating system. [2 Marks]
