Operating system common services

1)    Program execution

2)    i/o operations

3)    File system manipulation

4)    Communication

5)    Error Detection

6)    Resource Allocation

7)    Protection

1)   Program execution

The operating system handles many kinds of activities from user programs to system programs like printer spooler, name servers, file server ……. Each of these activities is encapsulated as a process.

Following are the major activities of an operating system

Ø  Loads program into memory

Ø  Executes the Program

Ø  Handle programs execution

Ø  Provides a mechanism for process synchronization

Ø  Provides a mechanism for deadlock handling

2)   I/O operation

The I/o subsystem comprises of i/o devices and their corresponding driver software. Drivers hide the peculiarities of specific hardware devices from the users. The Os manage the communication between the user and device drivers

Ø  I/O operation means to read or write operation with any file or any specific I/O device

Ø  Os provides the access to the required I/O device when required

3)   File system manipulation

A file represents a collection of related information. Computers can store files on the disk, for long-term storage purpose. Example of storage media includes magnetic tape, magnetic disk and optical disk drives like cd, DVD. Its own properties liked speed, capacity, data transfer rate and access methods.

Following are the major activities of OS with File management

Ø  Program needs to read or write file

Ø  OS the permission to program operation on the file

Ø  OS system provides an interface to the user to create or delete files.

Ø  OS provides an interface to create the backup of the file system