Test Papers / Previous Question Papers of IGNOU CS02 Introduction to Software December 2005

PGDCA / MCA (I Yr) / BCA
Term-End Examination

December, 2005

CS02 (S) : Introduction to Software

Time: 2 hours
Maximum Marks: 60

1. (a) Design an algrorithm and draw a flowchart to find the maximum of a list of n numbers, n > 0. (7)

(b) Construct a context free grammar for
(i) Increment and Decrement statements in C
(ii) if-then-else statement
(iii) Switch statement

(c) Write Unix shell programs to: (8)
(i) Check whether a number is prime.
(ii) Check whether a substring occurs in a string.

(d) Consider the following set of processes that arrive in the ready queue at the same time :

Process         CPU Time
Job 1                  4
Job 2                  3
Job 3                  6
Job 4                  5
Job 5                  2

Consider the following scheduling algorithms :
First Come First Served (FCFS) and Round Robin
(quantum=1)

2. (a) List all the permissions that are allowed on UNIX files. How can you change these files permissions ? Explain this through an example. (5)
(b) What is Paging ? How does it solw the problem ofexternal fragmentation ? With the help of a diagram explain the address mapping in the paging system. (5)

3. (a) What is a semaphore ? Write an algorithm to explain how semaphores can solve the problem of Mutual Exclusion. (5)
(b) Explain any five qualities of a software product and process. Illustrate each of them through a single example. (5)

4. (a) Explain all the design phases of a compiler. (6)
(b) Write the UNIX commands for the following : (4)
(i) To view all processes running including user and system processes
(ii) To produce a list of all files in the current directory without headers, but in three columns.
(iii) From two sorted lists of names, finding out the number of names that are common to both.
(iv) To find out the number of times the character "?" occurs in a file.

5. (a) List the four major components of GUI, and explain the functioning of any two. (5)
(b) Explain all the stages of the SDLC with the help of an example. (5)