A. Multiple Choice Questions (60 questions) Subject: Operating System (BTCOC403) Class: S.Y.B.Tech. (Computer Engineering) Unit-I 1. What is operating system? a) collection of programs that manages hardware resources b) system service provider to the application programs c) link to interface the hardware and application programs d) all of the mentioned 2. To access the services of operating system, the interface is provided by the a) System calls b) API c) Library d) Assembly instructions 3. Which one of the following is not true? a) kernel is the program that constitutes the central core of the operating system b) kernel is the first part of operating system to load into memory during booting c) kernel is made of various modules which can not be loaded in running operating system d) kernel remains in the memory during the entire computer session 4. Which one of the following error will be handle by the operating system? a) power failure b) lack of paper in printer c) connection failure in the network d) all of the mentioned 5. The main function of the command interpreter is a) to get and execute the next user-specified command b) to provide the interface between the API and application program c) to handle the files in operating system 6. If a process fails, most operating system write the error information to a a) log file b) another running process c) new file 7. The OS X has a) monolithic kernel
b) hybrid kernel c) microkernel d) monolithic kernel with modules 8. Fork is a) the dispatching of a task b) the creation of a new job c) the creation of a new process d) increasing the priority of a task 9. Which is single user operating system a) MS-DOS b) UNIX c) XENIX d) LINUX 10. Which operating system reacts in the actual time a) Batch system b) Quick response system c) Real time system d) Time sharing system 11. Multiprogramming systems a) Are easier to develop than single programming systems b) Execute each job faster c) Execute more jobs in the same time d) Are used only on large main frame computers 12. Time sharing OS is logical extension of a) Batch OS b) Real time OS c) Multiprogramming OS d) Multitasking OS 13. Which of the following is example of Hard RTOS a) RT Linux b) Embedded Linux c) MC Linux d) Windows 8 14. Deadlock handling is done by which OS component a) Main memory management b) File management c) I/O subsystem management d) Process management
15. System call is a) Interface between process and processor b) Interface between OS and memory c) Interface between process and OS d) Interface between OS and secondary memory 16. The OS structure formed of a single large block is called as a) Kernel based structure b) Microkernel based structure c) Layered structure d) Monolithic structure 17. UNIX OS has a) Kernel based structure b) Microkernel based structure c) Layered structure d) Monolithic structure 18. Which of the following can be a perfect vehicle for OS research and development a) Virtual machine b) Kernel based OS structure c) RTOS d) Distributed OS 19. OS is interface between a) User and program b) User and computer hardware c) Program and memory d) Memory and hardware 20. is a special type of programming language used to provide instructions to the monitor simple batch processing schema. a) Job control language (JCL) b) Processing control language (PCL) c) Batch control language (BCL) d) Monitor control language (MCL) Unit-II 1. The systems which allows only one process execution at a time, are called a) uniprogramming systems b) uniprocessing systems c) unitasking systems
2. In operating system, each process has its own a) address space and global variables b) open files c) pending alarms, signals and signal handlers d) all of the mentioned 3. A process can be terminated due to a) normal exit b) fatal error c) killed by another process d) all of the mentioned 4. What is the ready state of a process? a) when process is scheduled to run after some execution b) when process is unable to run until some task has been completed c) when process is using the CPU 5. What is interprocess communication? a) communication within the process b) communication between two process c) communication between two threads of same process 6. A process stack does not contain a) Function parameters b) Local variables c) Return addresses d) PID of child process 7. The address of the next instruction to be executed by the current process is provided by the a) CPU registers b) Program counter c) Process stack d) Pipe 8. A Process Control Block(PCB) does not contain which of the following : a) Code b) Stack c) Bootstrap program d) Data 9. The number of processes completed per unit time is known as a) Output b) Throughput c) Efficiency
d) Capacity 10. The state of a process is defined by: a) the final activity of the process b) the activity just executed by the process c) the activity to next be executed by the process d) the current activity of the process 11. Which of the following is not the state of a process? a) New b) Old c) Waiting d) Running 12. The Process Control Block is: a) Process type variable b) Data Structure c) A secondary storage section d) A Block in memory 13. The degree of multiprogramming is: a) the number of processes executed per unit time b) the number of processes in the ready queue c) the number of processes in the I/O queue d) the number of processes in memory 14. Which of the following do not belong to queues for processes? a) Job Queue b) PCB queue c) Device Queue d) Ready Queue 15. What is a medium-term scheduler? a) It selects which process has to be brought into the ready queue b) It selects which process has to be executed next and allocates CPU c) It selects which process to remove from memory by swapping d) None of the mentioned 16. The primary distinction between the short term scheduler and the long term scheduler is : a) The length of their queues b) The type of processes they schedule c) The frequency of their execution d) None of the mentioned 17. In a time-sharing operating system, when the time slot given to a process is completed, the process goes from the running state to the :
a) Blocked state b) Ready state c) Suspended state d) Terminated state 18. An IPC facility provides at least two operations : a) write & delete message b) delete & receive message c) send & delete message d) receive & send message 19. Which module gives control of the CPU to the process selected by the short-term scheduler? a) dispatcher b) interrupt c) scheduler 20. Which scheduling algorithm allocates the CPU first to the process that requests the CPU first? a) first-come, first-served scheduling b) shortest job scheduling c) priority scheduling Unit-III 1. Concurrent access to shared data may result in : a) data consistency b) data insecurity c) data inconsistency 2. A situation where several processes access and manipulate the same data concurrently and the outcome of the execution depends on the particular order in which access takes place is called : a) data consistency b) race condition c) aging d) starvation 3. The segment of code in which the process may change common variables, update tables, write into files is known as : a) program b) critical section c) non critical section d) synchronizing
4. The following conditions must be satisfied to solve the critical section problem : a) Mutual Exclusion b) Progress c) Bounded Waiting d) All of the mentioned 5. Mutual exclusion implies that : a) if a process is executing in its critical section, then no other process must be executing in their critical sections b) if a process is executing in its critical section, then other processes must be executing in their critical sections c) if a process is executing in its critical section, then all the resources of the system must be blocked until it finishes execution 6. The TestAndSet instruction is executed : a) after a particular process b) periodically c) atomically 7. Semaphore is a/an to solve the critical section problem. a) hardware for a system b) special program for a system c) integer variable 8. The two atomic operations permissible on semaphores are : a) wait b) stop c) hold 9. The main disadvantage of spinlocks is that : a) they are not sufficient for many process b) they require busy waiting c) they are unreliable sometimes d) they are too complex for programmers 10. If the semaphore value is negative : a) its magnitude is the number of processes waiting on that semaphore b) it is invalid c) no operation can be further performed on it until the signal operation is performed on it
11. The two kinds of semaphores are : a) mutex & counting b) binary & counting c) counting & decimal d) decimal & binary 12. A semaphore : a) is a binary mutex b) must be accessed from only one process c) can be accessed from multiple processes 13. The bounded buffer problem is also known as : a) Readers Writers problem b) Dining Philosophers problem c) Producer Consumer problem d) None of the mentioned 14. In the bounded buffer problem, there are the empty and full semaphores that : a) count the number of empty and full buffers b) count the number of empty and full memory spaces c) count the number of empty and full queues 15. To ensure difficulties do not arise in the readers writers problem, are given exclusive access to the shared object. a) readers b) writers c) readers and writers 16. The dining philosophers problem will occur in case of : a) 5 philosophers and 5 chopsticks b) 4 philosophers and 5 chopsticks c) 3 philosophers and 5 chopsticks d) 6 philosophers and 5 chopsticks 17. A monitor is a type of : a) semaphore b) low level synchronization construct c) high level synchronization construct 18. The operations that can be invoked on a condition variable are : a) wait & signal b) hold & wait
c) signal & hold d) continue & signal 19. The process invoking the wait operation is : a) suspended until another process invokes the signal operation b) waiting for another process to complete before it can itself call the signal operation c) stopped until the next process in the queue finishes execution 20. If no process is suspended, the signal operation : a) puts the system into a deadlock state b) suspends some default process execution c) nothing happens d) the output is unpredictable B. Three Marks Questions (15 questions) Unit-I 1. Define O.S.? List O.S. Types? [Remember/CO1] 2. Describe monolithic structure of OS. [Remember/CO1] 3. Explain micro-kernel structure of OS [Understand/CO1] 4. Justify the statement "Each layer in layered structured O.S. should be defined carefully". [Evaluate/CO1] 5. Explain in brief System Calls. [Understand/CO1] Unit-II 1. What is process control block? [Remember/CO2] 2. What are the use of job queues, ready queues and device queues? [Remember/CO2] 3. Draw and explain process state diagram. [Understand, Analyze/CO2] 4. Write a short note on context switch. [Remember/CO2] 5. Explain in brief IPC. [Understand/CO2] Unit-III 1. Define race condition. [Remember/CO3] 2. What is critical section problem? [Remember/CO3] 3. What are the requirements that a solution to the critical section problem must satisfy? [Remember/CO3] 4. Explain in brief: Semaphore [Understand/CO3] 5. Write a short note on Monitors. [Remember/CO3]
C. Eight Marks Questions (12 questions) Unit-I 1. Define operating system and list the basic services provided by operating system. [Remember/CO1] 2. Explain batch system and Multiprogrammed System in detail. [Understand/CO1] 3. Explain the terms: a) Real time System b) Distributed System [Understand/CO1] 4. Explain the concept of virtual machines. [Understand/CO1] 5. What are system calls? Explain different categories of system calls with example? [Remember/CO1] Unit-II 1. What are different types of schedulers? Explain with neat diagram. [Remember/CO2] 2. Explain multilevel queue scheduling with and without feedback. [Understand/CO2] 3. Consider following jobs to be Executing on a uniprocessor system [Analyze, Apply/CO2] Process AT BT Priority P1 0 10 3 P2 1 12 2 P3 2 5 1 P4 2 6 4 P5 5 3 5 Draw Gantt chart and calculate average waiting time and turnaround time for i) Preemptive Priority ii) Non-preemptive Priority Assume low number=high priority. 4. Consider following jobs to be Executing on a uniprocessor system Process AT BT P1 0 16 P2 0 10 P3 6 4 P4 7 6 P5 8 10 [Analyze, Apply/CO2] Draw Gantt chart and calculate average waiting time and turnaround time for i) SJF Preemptive ii) SJF Non-preemptive
5. Consider following jobs to be Executing on a uniprocessor system Process AT BT P1 0 5 P2 3 2 P3 1 3 P4 4 1 [Analyze, Apply/CO2] Draw Gantt chart and calculate average waiting time and turnaround time for i) SJF Preemptive ii) SJF Non-preemptive Unit-III 1. Explain dinning philosopher problem & its solution. [Understand/CO3] 2. Explain Peterson s solution for achieving mutual exclusion. [Understand/CO3] 3. Explain readers & writers problem? Give its solution with semaphore. [Understand/CO3] 4. Write short notes on: a) Critical section b) Race condition [Remember/CO3] 5. What are semaphores? Explain two primitive semaphore operations. What are its advantages? [Remember, Understand /CO3]