Functions of Operating System

 Functions of Operating System:

There are many functions those are performed by the operating system, but the main goal of operating system is to provide the interface between the user and the hardware means provides the interface for working on the system by the user. The various functions those are performed by the operating system, these are the following:-

1)      Input/ Output device management: In a process program takes an input and then produces an output. It takes the input through input devices and produces output through output devices. Thus, it has to handle input and output devices during program execution. It is very tedious to write instructions to directly handle the input and output devices through the user program. Therefore operating system provides device driver to handle input and output devices. Programmers can user these derivers in their program to control the input/output devices. The interaction of the program with the device drivers is via an operating system.

2)      Resource Management:  In a single user system, like ‘window’ management of memory is very critical, because more than one application are running at time. In a multiuser system many user works simultaneously. The operating system is very busy in serving each user. The management of these resources becomes very important. They share various resources like printer, plotter, RAM , CPU, files etc. sometime it may happens that more than one user may demand the same resource like a printer. The operating system solves these problems by maintaining a queue of priority job according to their priority. The jobs are then printed one after and another from the queue. Thus the important role at an operating system is to allocate appropriate resources to every user.

3)      Memory management: RAM is a costly part in a computer system. Its size is limited and therefore it is to be used very efficiently. This is particularly important is multitasking or multiuser system where more than one programs may be running at a time. The memory is to be shared among various applications in such a way that there is no interface in the working of programs.

Operating system is responsible for managing the memory space allocated to each application and, where relevant, to each user. If there is insufficient physical memory, the operating system can create a memory zone on the hard drive, known as "virtual memory". The virtual memory lets you run applications requiring more memory than there is available RAM on the system. However, this memory is a great deal slower.

4)      File Management: In many computational process input and output is directed towards file storage devices like CD, DVD and PEN derive etc. File storage is treated separately from other input and output devices, because they are needed to manage file activities like naming, storing , reading , writing , deleting, rename and executing. All such activities are handled by the operating system.

5)      Management of the processor: the operating system is responsible for managing allocation of the processor between the different programmers using a scheduling algorithm. The type of scheduler is totally dependent on the operating system, according to the desired objective.

6)      Security: Security is an important aspect relating to the file storage and other input/output devices. Security at the operating system level protects authorized access to the important data. The operating system can restrict file access to read only, execute only or read write. Many operating system also provides a logging process which permits  the user to operate the computer only after entering correct password.

7)      Information management: the operating system provides a certain number of indicators that can be used to diagnose the correct operation of the machine.