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Functions of Operating System

 

Functions of operating system

 

5.                   protection and security :

·                     another important functions of an operating system is to protect itself from the user process and to protect different users processes from one another in a syatem.

·                     In a multi programming environment, where several users process reside in main memory at the same time, the may interface with OS or with each other.

·                     Thus, protection mechanism controls the access of users, programs and processes used by various applications.

·                     A total approach to computer security involves both external and internal security.

 

6.                   Networking:

·         Networking is used for exchanging  information among different computer that are distributed across various location.

·         Distributed system consist of multiple processors and each processor has its own memory and clock

·         This results in computer speedup, increased functionality, increased data availability and better reliability.

·         Thus, a distributed system enables us to share the various resources of the network.

 

7.                   Command interpretation:

·         The command interpreter is the basic interface between the computer and the user.

·         There are to different user interface supported by operating system:

1.       Command line interface

2.       Graphical user interface

·                     Command line interface . it is the textual user interface on which user gives instruction to computer by typing the command.

·                     Graphical user interface . GUI provide the user a screen full of graphical icons or menus and allows the user to make a rapid selection from the displayed icons or menus to give instruction to computer.

·                     The various command supported by command interpretations module are known as system calls.

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