Unix and Shell Programming - Jun 2014

Computer Science Engg. (Semester 4)

TOTAL MARKS: 100
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks. 1 (a) With a neat diagram, explain the architecture of UNIX operating system. List the features also.(8 marks) 1 (b) Explain the parent-child relationship of UNIX file system with a diagram.(6 marks) 1 (c) Explain with examples:
i) Absolute pathname and relative pathname
ii) Internal and external commands.(6 marks) 2 (a) Interpret the significance of seven fields of ls -l output.(7 marks) 2 (b) Briefly explain the different ways of setting file permissions.(7 marks) 2 (c) With a diagram, explain 3 modes of Vi editor.(6 marks) 3 (a) What are wild cards? Explain the shells wild cards, with examples.(8 marks) 3 (b) What is a process? Explain the process creation mechanism? Why directory changed can't be made in separate process.(8 marks) 3 (c) Explain the following environment variables with examples:
i) HOME ii) PATH iii) IFS iv) SHELL(4 marks) 4 (a) What are hard links and soft links? Explain with examples.(6 marks) 4 (b) Write a short notes on find command.(6 marks) 4 (c) Explain the following filters with examples:
i) head ii) tail iii) cut(8 marks) 5 (a) Explain grep command with all options.(10 marks) 5 (b) What is sed? With example, explain line addressing and context addressing.(10 marks) 6 (a) What is shell programming? Write a shell script to create a menu which displays:
i) List of files ii) Contents of a file iii) process status
iv) Current date
v) Clear the screen vi) Current users of system.(10 marks) 6 (b) Explain the shell features of 'for'. With syntax and examples.(10 marks) 7 (a) What is an AWK? Explain all the built in variables used by awk.(10 marks) 7 (b) With syntax and examples, discuss the control flow statements used by awk.(10 marks) 8 (a) Write a Perl script to demonstrate the use of chop function.(6 marks) 8 (b) Write a perl script to find the square root of command line arguments.(6 marks) 8 (c) Explain the string handling functions of Perl with appropriate examples.(8 marks)