Operating System Questions

1. Define operating system (MU AP-96)
An operating system is a set of program that controls, co-ordinates and supervises the activities of the computer hardware and software.

2. What is the role of an os?

An OS acts as an interface between the user and the computer. It acts as The manager of the resources of the computer.

3. Write the functions of an OS(BU Ap-97)

(i) Memory Management.
(ii) Processor management.
(iii) Interrupt Handling.
(iv) Accounting.
(v) Automatic job sequencing.
(vi) Management and control of I/O devices

4. What is the need for an OS?
A medium is needed to communicate between the user and the m/c. An OS acts as a medium of interface

5. What are the characteristics of an OS(MSU Ap-96)
(i) User friendly .
(ii) Keep track of the status of eaCH RESOURCE.
(iii) Allows sharing of resources(H/W and S/W).
(iv) Provides adequate security.
(v) Protection.

6. What is a process?
A process is basically a program in execution. It is the unit of work in a Modern operating system.


7. What is meant by a process state?
When a process executes, it changes, its status. This is known as process's State.

8. What are the various process states ?

The various process states are
(i) new
(ii) ready
(iii) running
(iv) suspended
(v) terminated

9. How does a process differ from a job?(BDU Ap-96).
A process is an active entity with a program counter specifying the next instructions to execute and a set to associated resources, whereas a batch System executes jobs.(which is a collection of processes).

10. Differentiate program and a process?
A process is a program in execution(ie) A program is a passive entity, Where as a process is an active entity.


11. What is process control Block?
Each process is represented in the operating system by a process control Block(PCB) also called a task control block.

12. What is the function of a process control block?
A (PCB) contains many pieces of information associated with a specific Process. It serves as the repository for any information that may vary From process to process.


13. What are the information contained in a PCB?
A PCB contains pieces of information associated with a specific process, Namely

(i) process state
(ii) program counter
(iii) CPU register
(iv) CPU scheduling information
(v) Memory management information
(vi) Accounting information
(vii) I/O status information

14. What are the operations on process?
(i) create a process
(ii) destroy a process
(iii) suspend a process
(iv) resume a process
(v) change the priority of a process
(vi) block a process
(vii) wakeup a process
(viii) dispatch a process
(ix) enable a process to communicate with another

15. What are the operation involved in creating a process?
(i) name the process
(ii) insert it in the system’s known processes list(or) process table.
(iii) Determine the process’s initial priority
(iv) Create the process control block
(v) Allocate the process’s initial resource.

16. What is the nucleus or kernel of an operating system?

Kernel is the part of the OS which directly makes interface with the Hardware system.

17. What are the main functions of the kernel?

To provide mechanism for
(i) creation and deletion of processes
(ii) inter process communication
(iii) synchronization of processes.

18. What are the components of an OS?
OS which is a collection of programs are of 2 types
(i) control program
(ii) supervisory program


19. What is multi programming?
The ability of keeping several jobs in the memory at one time, where The cpu is switched back and forth among them is called as Multi programming

20. What is the use of Multi Programming ?
Multi programming helps to increase CPU utilization, and to decrease the total time needed to execute the jobs.

21. Illustrate the factors that usually determine the degree of Multi Programming
(MSU: Nov-96)
(i) The number of Programs residing in Primary memory.
(ii) Passing of the control of the CPU rapidly between these programs.
(iii) Protection of user process from one another.