BCA Paper - UNIX and Shell Programming (Set-1)

 UNIX and Shell Programming

Q1: Explain UNIX architecture and its salient features. Distinguish between INTERNAL and EXTERNAL commands.

Q2: Explain with examples different types of files supported in UNIX.

Q3: What is the output of the following commands:
   i.  echo $PATH
  ii.  ls -l/wc -l
 iii.  type mkdir; mkdir new;
  iv.  who > userlist

Q4: Explain man command with its option.

Q5: Explain briefly the file attributed listed using ls -l command

Q6: Explain with suitable example how and who can change file permission.

Q7: Explain different modes in vi editor and list commands in each mode.



Q8: How to do the following using vi editor:

1. Combine 5 lines in to single line
2. Move the cursor to last line in a file
3. Replace 'has' with 'have' in the current line
4. Add /* at the beginning of line and */ at the end of the line.

Q9:  Explain the mechanism of a process creation and role of system calls.

Q10: Explain the following commands with suitable example and list its options:

1. ps
2. kill

Q11: Define job. How is job control done in UNIX? Explain with example.

Q12: What are environment variables that control UNIX system? Explain any three such variables.

Q13: Explain with example find command and its options.

Q14: Write a note on sort command. Discuss its options with examples.

Q15: Explain the following commands:

1. ls -l | grep "^d" > directories
2. grep -v "USA" news.txt | wc -l
3. sed '10,$ s/loop/ loop with in loop/g' <loop.txt> moreloops
4. grep "$SHELL$" /etc/passwd | cut -d ":" f1
5. grep a b c > found.txt

Q16: What is sed? Explain with example line addressing and context addressing in sed.

Q17:  What is shell programming? Write a shell script to create a menu which displays the list of files, current users, contents of a particular file and process status of the system based on the user choice.

Q18: Explain the expr command applicable to numeric and string functions.

Q19: Explain the following with reference to shell programming:

1. $?
2. test
3. shift
4. trap

Q20: Write a shell script to display list of all processes running in the system every 30 seconds for five times using a

• while loop
• for loop

Q21: Write a note on awk. Explain built-in variables.

Q22: Write an awk sequence to find the DA, HRA and gross pay of employees. DA at 50% of basic, HRA at 25% of basic and the gross pay is sum of basic pay, DA and HRA. Also compute the average gross pay.

Q23: Explain with example the following built in functions:

1. split( )
2. substr( )
3. length( )
4. index( )

Q24: Explain the following in PERL program:

1. $_default variable
2. foreach loop construct
3. join( )

Q25: Write a PERL program that accepts decimal number as arguments and convert it into binary number.

Q26: Using command line arguments, write a PERL program to find whether the given year is leap year.