fun and objectives of os.pdf

Why to Learn Operating System? An Operating System (OS) is an interface between a computer user and computer hardware. An operating system is a software which performs all the basic tasks like file management, memory management, process management, handling input and output, and controlling p...

Why to Learn Operating System? An Operating System (OS) is an interface between a computer user and computer hardware. An operating system is a software which performs all the basic tasks like file management, memory management, process management, handling input and output, and controlling peripheral devices such as disk drives and printers. Some popular Operating Systems include Linux Operating System, Windows Operating System, VMS, OS/400, AIX, z/OS, etc. Abstract view of Operating System Objectives of Operating System Convenience: Computer system can be conveniently used due to operating system. Efficiency: Operating system permits the computer system resources to be used in an efficient manner. Ability to evolve: The O.S. is built in such a manner that ,it allows the efficient development ,testing and introduction of new system function without interfering with services. Following are some of important functions of an operating System. Memory Management Process Management Device Management File Management Security Control over system performance Job accounting Error detection Coordination between other software and users Process Management In multiprogramming environment, the OS decides which process gets the processor when and for how much time. This function is called process scheduling. An Operating System does the following activities for processor management − Keeps tracks of processor and status of process. The program responsible for this task is known as traffic controller. Allocates the processor (CPU) to a process. De-allocates processor when a process is no longer required. Device Management An Operating System manages device communication via their respective drivers. It does the following activities for device management − Keeps tracks of all devices. Program responsible for this task is known as the I/O controller. Decides which process gets the device when and for how much time. Allocates the device in the efficient way. De-allocates devices. File Management A file system is normally organized into directories for easy navigation and usage. These directories may contain files and other directions. An Operating System does the following activities for file management − Keeps track of information, location, uses, status etc. The collective facilities are often known as file system. Decides who gets the resources. Allocates the resources. De-allocates the resources.  Security − By means of password and similar other techniques, it prevents unauthorized access to programs and data. Control over system performance − Recording delays between request for a service and response from the system. Job accounting − Keeping track of time and resources used by various jobs and users. Error detection − Production of dumps, traces, error messages, and other debugging and error detecting aids. Coordination between other softwares and users − Coordination and assignment of compilers, interpreters, assemblers and other software to the various users of the computer systems.