Services Provided by Operating System

Services Provided by Operating System:

An operating system provides an environment for the execution of user programs. It provides certain services to programs and to the users of those programs. The specific services provided, of course, differ from one operating system to another operating system. These operating system services are provided for the convenience of the programmer, to make the programming task easier and more efficiently.

The following diagram is shows various operating system- 


 

 

 

 

 

 

 

 

              Figure: Operating System Services

These are the following services provided by operating system-

User Interface: Almost all operating systems have a user interface. This interface can take several forms. One is a command-line interface, which uses text commands and a methods for entering them. Another is a batch interface, in which commands and directives to control those commands, they are entered into files and those files are executed (that file is known as batch). Most commonly, a graphical user interface (GUI) is used. There, the interface is a window system with a pointing device to direct input and output, choose form menu, and make selections and a keyboard to enter text.

Program Execution: The system must be able to load a program into memory and to run that program. The program must be able to end its execution, either normally or irregular.

Input/output Operation: Input/output (I/O) management involves controlling the flow of data into and out of a data processing. A running program may require input and output devices, which may include a file or an input and output devices. For efficiency and protection, users usually cannot control input and output devices directly. Therefore, the operating system must control the input and output.

File system: Program need to read and write files and directories. They also need to create and delete them by a name, search for a given file, and list file information. Many operating systems provide a variety of file systems and sometimes to provide specific features.

Communications: There are many formalities in which one process needs to exchange information with another process. Such communication may occur between processes that are executing on the same computer. Communication may be implemented via shared memory or through message passing, in which packets of information are moved between processes by the operating system.

Error Detection: The operating system needs to be unchanging aware of possible errors. Error may be occurring in the CPU and memory hardware, in input and output devices and in the user program. For each type of error, the operating system should take the appropriate action to ensure correct and conformable computing, operating system correct error. 

Resource allocation: When there are multiple tasks running at the same time, resources must be allocated to each of them. Many different types of resources are managed by the operating system.

Accounting: We want to keep track of which users use how much and what types of computer resources. This record keeping may be used for accounting.

Protection and Security: When several separate processes execute concurrently, it should not be possible for the one process to interface with the others or with the operating system itself. Protection includes ensuring that all access to system resources is controlled. Security of the system from outsiders is also important. Such security starts with requiring each user to authenticate himself or herself to the system, usually by means of password, to gain access to system resources.

 

 

 

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