Every process is represented in the operating system by a process control block also called a task control block.A process control block (PSB) contains many pieces of information that is associated with a specific process includes the following −Process state.Program counter.CPU registers.CPU scheduling.CPU scheduling information.Memory management information.Accounting information.I/O status information.The structure of a process control block is as follows −Process stateProcess numberProcess counterRegisterMemory limitsList of open files----------Let us discuss each task in detail.Process state − The state may be a new state, ready state, running state , waiting state, terminated state and so on.Program counter − It indicates the address ... Read More

A process is a program in execution and it is more than a program code called as text section and this concept works under all the operating system because all the task perform by the operating system needs a process to perform the taskThe process executes when it changes state. The state of a process is defined by the current activity of the process.Each process may be any one of the following states −New − The process is being created.Running − In this state the instructions are being executed.Waiting − The process is in waiting state until an event occurs ... Read More

A process is a program in execution and it is more than a program code called as text section and this concept works under all the operating system because all the task perform by the operating system needs a process to perform the taskThe process executes when it changes state. The state of a process is defined by the current activity of the process. It is important to know that only one process can be running on any processor at any instant. Many processes may be ready and waiting.Five state process ModelThe states present in the 5-state model are as ... Read More

The System calls for File management are as follows −A file is open using a system call open. The mode in which the file is supposed to be open is specified using the parameter.Parameters also consist of the names of the file to open or a new one to be created. The files are closed using the close systems.Associated with each file is a pointer that indicates the current position in the file. When reading or writing sequentially, points to the next byte to be read or written.The Lseek call changes the value of the position pointer so that subsequent ... Read More

The major differences between single processor and multi-processor are as follows −ParameterSingle Processor SystemsMultiprocessor SystemsDescriptionThe name itself is saying that the single processor system contains only one processor for processing.For this also the name itself indicates that the multiprocessor system contains two or more processors for processing.Is there any use of Co-Processors?There is a use of a coprocessor in single processors because it uses multiple Controllers which are designed to handle special tasks and that can execute limited instruction sets. For example − DMA Controller.Multiprocessor uses two types of approaches −In Symmetric Multiprocessing every processor performs all the tasks within ... Read More

A process is a program in execution and it is more than a program code called as text section and this concept works under all the operating system because all the task perform by the operating system needs a process to perform the taskThe process executes when it changes the state. The state of a process is defined by the current activity of the process.Each process may be in any one of the following states −New − The process is being created.Running − In this state the instructions are being executed.Waiting − The process is in waiting state until an ... Read More

To begin with, let us learn about the process.ProcessA process is a program in execution and it is more than a program code called a text section and this concept works under all the operating systems because all the tasks performed by the operating system needs a process to perform the task.A process also known as one type of activity and it is used in the computer for a particular purpose and a number of states involved in this concept.A process is one type of state and the state of a process is defined in part by the help of ... Read More

Let us learn about the application programming interface.Application programming interfaceWe know that multiple devices and applications share data between them. Some devices include online reservations and some in booking systems.API (Application Programming Interface) is used to establish connectivity among devices and applications. However, it is an interface which takes the requests from the user and informs the system about what has to be done and returns the response back to the user.ExampleConsider an online travel agency having information about multiple airlines. The travel agency interacts with the airline’s API.The Application interface takes the requests from the customer to book seats ... Read More

Distributed Operating System is a type of model where applications are running on multiple computers linked by communications. It is an extension of the network operating system which supports higher levels of communication and integration of the machines on the network.Distributed OS runs on multiple CPUs but for an end-user, it is just an ordinary centralized operating system. It can share all resources like CPU, disk, network interface, nodes, computers, etc. from one site to another site, and it increases the data available on the entire system.All processors are connected by valid communication media such as high-speed buses and telephone ... Read More

The operating system can be broken into pieces that are smaller in size and this type of operating system is called MS-DOS, an UNIX OS and OS which is having greater control over the computer.When a layered structure is used then we can divide the OS into different layers and the OS is broken into a number of layers, the bottom layer is layer 0 and highest layer is layer N and a user interface connects all layers with each other.The different layers in a layered structure are as follows −Layer 0 deals with the allocation of processors, it always ... Read More