operating system service are responsible for the management platform resources

1. BY
G.KARTHIGA
M.SC INFO TECH
NADAR SARAWATHI COLLEGE OF ARTS AND SCIENCE,
THENI.

2.  An operating system provides an environment for the
execution of program.
 It provides certain services to programs and to the
user of those programs.
 The specific services provided differ from one
operating system to another.
 These operating system services are provided for the
convenience of the programmer to make the
programing task easier

3.  The operating system provides certain services to programs
and to the user of those programs.
 These services include:
1)User interface
2)Program execution
3)I/O operations
4)File system management
5)Communications
6)Error detections and handlings
7)Resources allocations
8)Accounting
9)Protection

4.  All operating system have a user interface.
 Command line interface which uses text command
and a method.
 Batch method in which command and directives to
control those command are entered into files.
 Graphical user interface is a window system with
pointing device to direct i/o, choose from menu and
make selection and a keyboard to enter text.

5.  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 abnormally.
 A process may include the complete execution
context of code to execute, data to manipulate,
register, OS resource in use

6.  A running program may require I/O which may
involves a file or an I/O device.
 For efficiency and protection users usually cannot
control I/O device directly.
 An operating system manage the communication
between user and device drivers.

7.  The file system is or particular interest.
 Program need to read or write files and directories.
 They also need to create and delete them by name,
search for a given file, and list file information.
 Some program include permission management to
allow or deny access to files or directories based on
file ownership.

8.  There are many circumstance in which one process
needs to exchange information with another process.
 Communication may be implemented via shared
memory or though message passing in which
packets of information are moved between by the
operating system.

9.  The operating system needs to be constantly aware of
possible errors .
 Error may occur in the CPU and memory hardware
,in I/O devices, and in the user program.
 Debugging facilities can greatly enhance the user’s
and programmer’s abilities to use the system
eeficiently.

10.  RESOURCE ALLOCATION: There are multiple
users or multiple jobs running at the same time,
resource must be allocated to each of them.
 ACCOUNTING: This record keeping may be used
for accounting or simply for usage statistics.
 PROTECTION AND SECURITY: The owner of
information networked computer system may want to
control use of that information.