Download OPERATINGSYSTEMS 2015

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Module Specification Sheet
TABLE OF CONTENTS
1.
GENERAL INFORMATION
2.
WHAT IS THE COURSE ABOUT ?
3.
COURSE OBJECTIVES
4.
COURSE PRE-REQUISITES
5.
LEARNING OUTCOMES
6.
VENUE AND HOURS/WEEK
7.
FACULTY DETAILS
8.
MODULE MAP
9.
RECOMMENDED BOOKS/JOURNALS/WEBSITES
10.
ASSESSMENT
11. QUESTION BANK
12.
BRAIN BANK
Dept. Of MCA
PESIT BSC
2015
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Module Specification Sheet
1.
GENERAL INFORMATION
Academic Year
Semester
Title
Operating Systems
:
:
2015
II
Code
Duration (Hrs)
Lectures
52 Hrs
13MCA24 Seminars
4 Hrs
Total
2.
56 Hrs
WHAT IS THE COURSE ABOUT ?
Operating system (OS) is the most important type of system software in a
computer system. Without an operating system, a user cannot run an
application program on their computer. Operating systems are found on
almost any device that contains a computer – from cellular phones and
video game consoles to supercomputers and web servers.
The course covers the following essential concepts: Processes, Memory
Management, File Systems, I/O Devices and Deadlocks.
The module aims to provide the students with an understanding of the role
of the operating system as a resource manager and the data structures and
algorithms used in the implementation of the operating system. The lab
sessions will enable the students to get familiar with the Linux
Operating System.
3.
4.
COURSE OBJECTIVES

To expose students to underlying concepts and design principles of
Operating Systems.

To familiarise students with the use of operating system primitives
such as system calls, files, processes, threads, synchronization
and communication mechanisms.
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COURSE PRE-REQUISITES

Extensive programming skills in C language, equivalent to
Programming Techniques.

Understanding of data structures.
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5.
LEARNING OUTCOMES
By the end of the course students will be able to describe the basic
principles used in the design of modern operating systems. In particular,
they will:
6.
•
be able to distinguish different styles of operating system design.
•
understand device and I/O management functions in operating systems
as part of a uniform device abstraction.
•
have an understanding of disk organisation and file system
structure.
•
be able to give the rationale for virtual memory abstractions in
operating systems.
•
understand the main principles and techniques used to implement
processes and threads as well as the different algorithms for
process scheduling.
•
understand the main mechanisms used for inter-process
communication.
•
understand the main problems related to concurrency and the
different synchronization mechanisms available.
•
have the ability to evaluate security risks in operating systems
and understand the role operating systems can and should play in
establishing security.
VENUE AND HOURS/WEEK
All lectures will normally be held on V Floor.
Lecture Hours/week: 4Hrs
7.
FACULTY DETAILS
Name
Mr. Dilip Kumar Maripuri
Department
MCA
Designation
Associate Professor
Room No
509, Fifth Floor
Email
Address
[email protected],
[email protected]
Dept. Of MCA
PESIT BSC
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8.
Class
#
MODULE MAP
Unit #
2
4
5
8
9
10
11
Chapter-2
Operating
Systems :
System
Structures
Chapter-3
Process
Management
27
51.9%
Execution of the Operating System, Security
Issues
Processes and Threads
Principles of Concurrency
26
04
System Generation
18
25
44.2%
System Design and Implementation
CPU Scheduler and Scheduling
24
06
System Structure, Virtual Machines
17
23
32.6%
System Calls, System Programs
Symmetric Multiprocessing(SMP), Micro kernels,.
22
06
System Components, Operating – System Services
16
21
21.1%
Handheld Systems, Feature Migration, Computing
Environments
Process Description, Process Control
20
05
Distributed Systems, Clustered Systems, Real Time Systems
13
19
11.5%
Introduction to Operating System, Mainframe
Systems, Desktop Systems, Multiprocessor Systems
Process, Process States
15
06
I/O Communication Techniques
12
14
Cum.
%
Interrupts, The Memory Hierarchy, Cache Memory
Chapter-1
Introduction :
Computer and
Operating
Systems
6
7
Ref.
Chap
Basic Elements, Processor Registers, Instruction
Execution
1
3
Topic Outline
% Portions
Covered
Mutual Exclusion
Chapter-4
Hardware Support , Semaphores
Mutual
Execution and Monitors
Synchronization
Message Passing
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Readers/Writes Problem
Principles of Deadlock
Chapter-5
Deadlock and
Starvation
Perservance
Deadlock Prevention, Deadlock Avoidance
Deadlock Detection, An Integrated Deadlock
Strategy
Dining Philosophers Problem
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Module Specification Sheet
Class
#
Unit #
Topic Outline
28
Memory Management strategies: Background,
29
Swapping, Contiguous Memory Allocation
30
Paging, Structure of the page table
31
32
Chapter-6
Memory
Management
34
Page Replacement (Continued)
35
Allocation of Frames, Thrashing
36
File Concept
37
Access Methods, Directory Structure
40
Directory Implementation, Allocation Methods
42
Free space management
44
45
Chapter- 8
Secondary
Storage,
Computer
Security
Linux History, Design principles
51
52
80.7%
04
88.4%
06
100%
The Security Problem, User Authentication
47
50
07
Disk Scheduling, Disk management
Program Threats, System Threats.
49
67.3%
Mass Storage Structures: Disk Structure, Disk
Attachment
46
48
08
Chapter-7
File system mounting, File sharing
File system,
Protection
Implementation
of File System File system structure, File system
implementation
41
43
Cum.
%
Virtual Memory Management: Background, Demand
Paging
Page Replacement
39
Ref.
Chap
Segmentation
33
38
% Portions
Covered
Kernel modules
Chapter- 9
Case Study: The Process management, Scheduling
Linux OS
Memory management
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File systems
Input and Output, Inter-process communication
9. RECOMMENDED BOOKS/JOURNALS/WEBSITES
a.PRESCRIBED TEXTBOOK
a.Text Book 1 - Operating System Principles: A. ,Silberschatz, P.
Galvin, G. Gagne, 8 th Edition, Wiley – India, 2009
b.Text Book 2 -“Operating Systems – Internals and Design Principles”,
William Stallings, Pearson, 6th edition, 2012
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b.REFERENCE BOOKS
a.R1 (Reference Book 1) - Operating Systems-A Concept based Approach:
D.M. Dhamdhere, 2 nd Edition, Tata McGraw-Hill, 2002.
b.R2 (Reference Book 2) - Introduction to Operating systems- Concepts
and Practice: P.C.P Bhatt, 2 nd Edition, PHI, 2008.
c.R3 (Reference Book 3) - Operating Systems: Harvey M Deital, 3
Edition,Pearson Education , 1990.
10.
rd
ASSESSMENT
a.WRITTEN EXAMINATION
QUESTION PAPER STRUCTURE
No.of Questions
8 Main Questions
No. of Questions to be answered
5
Examination Date
November 2013
Paper Duration
3 Hrs
Total Marks
100
Pass Marks
40
b.CONTINUOUS ASSESSMENT
Weighting (%)
Assignment(s):5 Marks (10%)
Seminar(s)
5 Marks (10%)
Test(s)
40 Marks (80%)
Total Marks
50 Marks
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c.INTERNAL TEST PORTIONS
Test 1:Chap. 1, 2, 3
Test 2:Chap. 3, 4, 5
Test 3 :Chap. 6, 7, 8, 9
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11. QUESTION BANK
Chapter 1: Introduction to operating system, System Structures
Objective: This chapter gives an introduction about the operating system,how
they are designed and constructed. The common features of an operating system
are discussed.
1.What is an operating system? What are the functionalities of an OS?
2.Explain various components of an OS.
3.What are the services provided by an OS?
4.Explain the following types of OS:
i.Batch
ii.
Real–Time
iii.
Time–Sharing
iv.
Distributed systems
v.Multimedia systems
5.Briefly explain the layered approach to the structuring of an OS.
6.Discuss the need for an operating system.
7.What is Multiprogramming? What are the main advantages of
multiprogramming?
8.Differentiate between multiprogramming and time sharing.
9.List the operating system components.
10.
What is a thread? Mention the benefits of multithreaded
programming.
11.
Discuss the microkernel briefly.
12.
Explain the following:
i.Tightly coupled system
ii.
Loosely coupled system
13.
Explain the following:
i.Multiprocessor Systems
ii.
Clustered Systems
14.
What are system calls? Explain.
15.
What is virtual machine? Explain VMware architecture?
Chapter 2: Process Management
Objective: This chapter describes the process concept and concurrency of
modern operating systems. Topics under this chapter also cover methods for
process scheduling and interprocess communication.
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16. What is a process? With the help of a diagram, explain the different
states of a process.
17. Explain the process control block , in detail.
18. What is CPU Scheduling? What is the difference between preemptive and
non- preemptive scheduling?
19. What are the various reasons for allowing concurrent execution of
processes?
20. What is thread? Explain the concept of multithreading and their various
models.
21. Discuss the benefits of multithreaded programming.
22. What is CPU Scheduling?
23. What is a scheduler? Explain different types of schedulers.
24. Explain the different criteria to select a scheduling algorithm.
25. Explain First Come First Serve Scheduling Algorithm.
26. Explain Shortest Job First Scheduling Algorithm.
27. Explain Round Robin Scheduling Algorithm.
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28. Explain Priority Scheduling Algorithm.
29. Explain multilevel queue scheduling and multilevel feedback queue
scheduling with illustration.
30. Differentiate between direct communication and indirect communication.
31. Describe the use of mailboxes in inter process communication
32. Explain the concept of messages with reference to inter process
communication.
33. 5 batch jobs A, B, C, D, E arrive at a computer center at almost the
same time. They have estimated running times of 10,6,2,4 and 8 seconds.
Their priorities are 3,5,2,1 and 4 respectively. For each of the
following draw Gantt Chart and compute turnaround time.
(i) RR (Quantum time 1 sec)
(ii) FCFS
(iii) Priority
(iv) SJF
34. What is context switching? Explain process context switching with
process state diagram. Also discuss short term and long term scheduler.
35. Describe some of the CPU scheduling algorithm evaluation methods.
36. Consider the following set of processes, which have arrived at the ready
queue with the burst time and the arrival time given in milliseconds as
shown below:
Processes
Burst Time
in milliseconds
Arrival Time
in milliseconds
P1
8
0
P2
4
1
P3
9
2
P4
5
3
Draw the Gantt chart and calculate the average waiting time using the following algorithms
(I)
First Come First Serve (FCFS)
(II)
Shortest Job First (SJF – pre-emptive).
37. Consider the following set of processes:
Processes
Burst Time
in milliseconds
Burst Time
P1
8
3
P2
5
1
P3
12
2
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P4
4
4
The processes are assumed to have arrived in the order P1, P2, P3, P4 all
at time 0. Obtain the Gantt chart, average waiting time using
(i)
First Come First Serve
(ii) Non Pre-emptive Shortest Job First
(iii) Non Pre-emptive priority-scheduling schemes.
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38. Consider the following processes which have arrived the ready queue with
the burst time and the arrival time given in milliseconds as shown
Processes
Burst Time
in milliseconds
Arrival Time
in milliseconds
P1
34
0
P2
12
1
P3
5
2
P4
6
3
Construct the Gantt chart and calculate the average waiting time using the
FCFS and SJF (preemptive).
39. Consider the following set of processes, with the length of the CPU
burst given in milliseconds.
Processes
Burst Time
in milliseconds
Arrival Time
in milliseconds
Priority
P1
10
0
4
P2
12
2
3
P3
14
3
5
P4
16
6
1
P5
5
30
1
1.Draw a Gantt chart that illustrates the execution of these
processes using the preemptive priority scheduling algorithm (a
smaller priority number implies a higher priority).
2.Calculate the average waiting time.
40. Suppose the following jobs arrive for processing at the times
indicated,each job will run the listed amount of time.
Arrival Time
Burst Time
Processes
in milliseconds
in milliseconds
P1
0
10
P2
1
15
P3
2
17
P4
3
20
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1.Draw a Gantt chart that illustrates the execution of these
processes using the preemptive priority scheduling algorithm (a
smaller priority number implies a higher priority).
2.Calculate the average waiting time. What is your conclusion?
41. Consider the following set of processes :
Burst Time
Processes
Priority
in milliseconds
Perservance
P1
6
3
P2
4
1
P3
10
2
P4
13
4
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The processes have arrived in the order P1, P3, P2 and P4. Obtain the
Gantt chart, waiting time using
(i) SJF
(ii) Pre-emptive priority-scheduling schemes.
Chapter 3: Process Synchronization
Objective: This chapter discusses the various mechanisms to ensure the orderly
execution of processes that share a logical address space, so that data
consistency is maintained. Various methods of process synchronization are
discussed.
42. What do you mean by semaphore? How do you access a semaphore?
43. What is a semaphore? Explain the role of semaphores in solving mutual
exclusion problem.
44. Define critical section problem and explain the requirements to be met
by a solution to the critical section problem.
45. Discuss any two classic problems of synchronization.
46. Explain the following terms:
i) Mutex
ii) Race condition
47. Explain the Readers-Writers problem in detail.
48. Explain Dining-Philosophers problem and its solution.
49. Define the bounded buffer problem and its solution.
50. List out the properties and characteristics of semaphores.
51. Give a solution to n-process critical section problem using
“Test-and-set” and show its correctness.
Chapter 4: Deadlocks
Objective: This chapter discusses about the deadlocks, various conditions
necessary for deadlock and different methods that an operating system can use
to prevent or deal with deadlocks.
52. What is deadlock? Explain four necessary conditions for a deadlock.
53. List different methods for handling deadlock. Explain deadlock
prevention in detail.
54. What is a safe state in a system?
55. Explain in detail with neat diagrams the resource allocation graph
technique to detect deadlock in a system.
56. What is a deadlock? Describe the necessary conditions for a dead lock.
Explain how deadlock can be prevented.
57. What is racing and deadlock? Why do they occur?
58. Consider the following snapshot of a system:
ALLOCATION
REQUEST
AVAILABLE
A
P0
0
P1
1
P2
2
P3
0
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B
C
A
B
C
1
0
1
0
1
2
1
2
2
1
3
0
1
2
3
1
1
1
4
3
A
B
C
1
0
2
a. What is the content of need matrix?
b. Is the system in SAFE state? If so, give the safe sequence.
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59. Consider the following snapshot of a system:
ALLOCATION
REQUEST
AVAILABLE
A
B
C
A
B
C
P0
0
1
0
7
5
3
P1
2
0
0
3
2
2
P2
3
0
2
9
0
2
P3
2
1
1
2
2
2
P4
0
0
2
4
3
3
A
B
C
3
3
2
a. What is the content of need matrix?
b. Is the system in SAFE state? If so, give the safe sequence.
60. With an example, illustrate Banker’s Algorithm for Dead lock avoidance.
Explain briefly about the deadlock avoidance.
Chapter 5: Memory Management
Objective: This chapter deals with main memory management during the execution
of a process. The different memory management schemes such as paging and
segmentation are discussed.
61. Explain the following with respect to memory management:
i) First Fit
ii) Best Fit
iii) Worst Fit
62. Bring out the difference between internal and external fragmentation.
63. What is page fault? What action does the operating system take when a
page fault occurs?
64. Explain paging with illustration.
65. Explain paging with demand scheme in handling virtual memory and how it
handles memory requests.
66. Define the structure of a page table.
67. Explain the following:
i) Hierarchical paging
ii) Inverted page table
68. Explain segmentation illustrating segmentation hardware.
69. Explain the concept of virtual memory.
70. Explain an implementation of LRU replacement policy.
71. When do page faults occur?
72. Discuss the steps in handling a page fault with the help of a neat
diagram.
73. Explain the following page replacement algorithms.
(i) FIFO page replacement
(ii) Optimal page replacement
74. Show how Translation Look aside Buffer (TLB) improves the performance of
paged system.
75. Discuss demand paging. Explain copy-on-write.
76. For the following reference string
1, 6, 2, 4, 3, 1, 2, 5, 6, 5, 1, 2, 3, 7, 3, 2, 1, 6, 4
How many page faults would occur for the page replacement algorithms:
LRU,FIFO and Optimal. Trace these algorithms for 3 frames. What is your
comment on these algorithms?
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77. Consider following reference string
7,0,1,2,0,3,0,4,2,3,0,3,2,1,2,0,1,7,0,1
How many page faults would occur for the page replacement algorithms:
LRU,FIFO and Optimal. Trace these algorithms for 3 frames. What is your
comment on these algorithms? Note that initially all the frames are
empty.
78. What is fragmentation? List the schemes for minimizing fragmentation.
79. Write short notes on Thrashing.
Chapter 6: File System, Implementation of File System
Objective: This chapter describe how the file system, mass storage and
I/O are handled in a modern computer system.
80. What is acyclic graph directory structure? Explain with example. Explain
the following:
i) File Operations
ii) Files Types
iii) File attributes
81. Explain different file access method.
82. What is access matrix? How is access matrix implemented?
83. Write a note on:
(i) Sequential Access
(ii) Direct Access
84. Write a note on:
i)
Single-level directory
ii)
Two-level directory
iii)
Tree-structured directories
iv)
Acyclic-Graph directories
85. What is a mount point? How a file is mounted and unmounted?
86. Discuss disk free space management.
87. Discuss directory implementation using:
(i) Linear list
(ii) Hash table
88. Describe the variable partition scheme with the allocation
policies–first fit, best fit and worst fit. Mention a disadvantage of
best fit.
89. Explain the different disk space allocation methods and compare them.
90. Name the different file allocation methods. Explain the linked
allocation method giving merits and demerits.
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Chapter 7: Secondary Storage Structures, Protection
Objective: This chapter discusses access to data and programs residing on
the disks. It also discusses how the processes in an operating system are
protected from one another’s activities. It also discusses the mechanism
for controlling the access of programs, processes or users to the
resources defined by a computer system.
91. What is disk scheduling? Explain FCFS disk scheduling algorithm.
92. Briefly explain the following disk scheduling policies and compare
them :
(i) FCFS
(II) SSTF
(III) SCAN
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93.
94.
95.
96.
Show that SCAN scheduling is not starvation free.
Compare SCAN and C-SCAN disk scheduling policies.
Compare LOOK and C-LOOK disk scheduling policies.
Write short note on:
i) Rotational Latency
ii) Swap Space Management
97. Suppose that a disk drive has 200 cylinders numbered 0 to 199. the disk
is currently serving a request at cylinder 53, and previous request was
at cylinder 65. The queue of pending requests in FIFO order is 98, 183,
37, 122, 14, 124, 65, 67. What is the total distance (in cylinders) that
the disk arm move to satisfy all the pending requests for each of the
below disk scheduling algorithms? Explain each with neat diagram.
i) FCFS
ii) SSTF
iii) SCAN
98. Explain the following.
i) Boot Block
ii) Bad Block
99. Differentiate between protection and security in the file system,
Explain access matrix implementation.
100. What is meant by denial of service?
101. What is authentication? Explain any two approaches for authentication.
102. What are the goals of protection?
103. Explain capability-based system with an example.
104. What is protection concept in OS, explain its Domain & Domain
Structure?
105. What is access matrix? Explain with neat figure. Explain any one of the
implementation method of access matrix.
106. Write short notes on the following:
i) Fragmentation
ii) Swap space management.
iii) Global table implementation of access matrix.
Chapter 8: Case Study: The Linux Operating System
Objective: This chapter presents an in-depth examination of the linux
operating system. It discuss the internal methods by which Linux
implements the interfaces.
107. With a diagram explain the components of the Linux system.
108. Discuss various kernel modules in Linux.
109. Explain process management and process scheduling in Linux operating
system.
110. Explain memory management and File systems in Linux operating system.
111. Explain Interprocess communication in Linux operating system.
112. Explain Input-Output in Linux operating system.
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12. BRAIN BANK
EXERCISE 1:
The command “man” in Unix systems allows the online display of the
manual for the commands and system calls. Further the re-direction
operator “>” allows the display to be sent to a file instead of the
terminal. Eg. “man fork > file1” will send manual information about fork
to the file file1. Use it to obtain such information and get a print-out
of the file to be used for this exercise.
1.
Write a program that reads 10 integers from the terminal and
places them in an array. The program should then fork. The parent process
should display the values in all the odd numbered elements while the
child displays values in the even numbered elements. For each display the
process displaying should indicate whether it is the parent or the child.
2.
Modify the above programs such that after the fork, the child
modifies values in all odd numbered elements. Each process should now
display all its elements.
EXERCISE 2:
The system call pthread_create allows the creation of threads in Linux
systems. The following program creates a thread, the parent executes a
loop 1000 times, then displays a message, sleeps for 2 seconds the whole
is repeated 10 times. The created thread is similar to the parent except
that it sleeps for 1 second instead of 2.
#include <pthread.h>
void * funct1(void * arg);
main()
{
pthread_t threadid;
int i,j;
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int x=1;
pthread_create(&threadid,NULL,funct1,(void *)&x);
for (j=0; j <10; j++)
{
for (i=0; i<1000; i++);
printf("Hi I'm the parent\n");
sleep(2);
}
}
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void * funct1(void * arg)
{
int i,j;
for (j=0;j<10; j++)
{
for (i=0; i<1000; i++);
printf("Hi I'm the created thread\n");
sleep(1);
}
}
1.
Type in the program, compile and execute it.
The command for compilation is:
cc <programname.c> -lpthread –o <objectfilename>
2.
Modify the program so that the created thread executes the loop
1000 times and exit, whereas the parent creates a new thread each time it
wakes up. The parent should pass as parameter a number (from 1 to 5)
indicating the sequence number of the created thread and the child thread
should display its sequence number. Note that the sequence number should
be cast as void when being passed to pthread_create and cast back to
integer within the thread.
3.
Modify the initial program so that it declares a global variable,
I, initialized as 0. Both the parent and child thread should increment I
each time they go into the loop. I should be protected by the use of
mutex locks.
Note: To use a mutex lock, it has to be declared of type
pthread_mutex_t.
Eg. pthread_mutex_t mylock;
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The mutex lock has to be initialized. This can be achieved at
declaration time using the macro PTHREAD_MUTEX_INITIALIZER.
Eg. pthread_mutex_t mylock = PTHREAD_MUTEX_INITIALIZER;
The commands pthread_mutex_lock and pthread_mutex_unlock perform the
locking and unlocking of mutex lock types.
Eg.pthread_mutex_lock(&mylock);
pthread_mutex_unlock(&mylock);
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EXERCISE 3:
The following system calls are used for dealing with files in Unix
systems:

open()

read()

write()

close()

seek() (or lseek())
Using man, find out how to use these system calls.
1.
Write a program that allows entry of information for a number of
students. The information for each student should consist of the
student’s names, address and course name. The information should be
stored in a file.
2.
Write a program that reads the information stored in the file in
Question 1 and displays them on the screen, one line per student.
3.
A company needs to store the following information about its
employees: Employee No. (an integer generated automatically), Employee
name (a string of 20 characters), Date of Birth (a string of 8
characters), position (a string of 20 characters). Write a program that
reads in the name, date of birth and position of 10 employees from the
terminal, generates the employee number (this is just a sequence of
integers starting from 1 and incrementing for each employee) and writes
the data in a file. Please note that all fields in the record are of
fixed length. Hence use blank characters to fill up the sizes of
character arrays as required.
4.
Write a program that reads an employee number (between 1 and 10)
from the terminal, uses seek (or lseek) to go to the appropriate position
in the file created in Question 3 and retrieves and displays the
information for the employee.
Dept. Of MCA
PESIT BSC
2015
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