Q1. Write a program to simulate Zombie process creation. 

• Create a child process that executes a simple task (e.g., a loop for a few seconds printing something) and then terminates using exit().

• The parent process should not immediately call wait() or waitpid(). Instead, it should sleep for a longer duration, allowing the child to terminate first.

• During this interval, use the system("ps -l") command to display the process states, demonstrating that the terminated child has become a zombie process (marked with Z or <defunct>).

• After observing the zombie state, the parent should call wait() to reap the child process and print a confirmation message. 

Q2. Consider the following set of processes.

Write a program to simulate Non-Preemptive Shortest Job First (SJF) scheduling algorithm . The program must output the following:

• A Gantt chart or a chronological log showing the execution sequence of processes on the CPU or order of Process execution.

• For each process (P1 to P5), calculate and display:

  • Finish Time: The time at which the process completes its final CPU burst.

  • Turnaround Time: (Finish Time - Arrival Time).

  • Waiting Time: The total time a process spends in the ready queue waiting for the CPU.

  • CPU Utilization

• Finally, calculate and display the average Turnaround Time and average Waiting Time and no. of context switches. 

Question 5 (10 Marks)

Write the Shell Commands for each of the following and show its output. {Hint: You can use Apropos command to search the manual page descriptions (man pages) for a given keyword, helping you find commands when you do not remember their exact names but know a related word or functionality}

1.       Write the command to display your current working directory.

2.       Change to your home directory using a single command.

3.       List all files and folders, including hidden ones, in the current directory.

4.       Move up one directory level from your current location.

5.       Go directly to the /etc directory from your current location.

6.       Create a new directory named practice_folder.

7.       Make an empty file called notes.txt inside practice_folder.

8.       Copy notes.txt to a file named notes_backup.txt in the same folder.

9.       Rename notes_backup.txt to notes_archive.txt.

10.   Delete the file notes_archive.txt.

Question 6. (10 Marks)

Write a bash script that asks the user for a starting and ending integer.

§  Use a loop (for or while) to traverse numbers in the range.

§  For each number, use a conditional statement (if) to check whether it is even.

Sum all even numbers (arithmetic with variables), and print the result at the end.