Operating System Articles - Page 118 of 171

Shared memory system is the fundamental model of inter process communication. In a shared memory system, in the address space region the cooperating communicate with each other by establishing the shared memory region.Shared memory concept works on fastest inter process communication.If the process wants to initiate the communication and it has some data to share, then establish the shared memory region in its address space.After that, another process wants to communicate and tries to read the shared data, and must attach itself to the initiating process’s shared address space.Message Passing provides a mechanism to allow processes to communicate and to ... Read More

An interrupt is a signal from a device attached to a computer or from a program within the computer that requires the operating system to stop and figure out what to do next.Interrupt systems are nothing but while the CPU can process the programs if the CPU needs any IO operation. Then, it is sent to the queue and it does the CPU process. Later on Input/output (I/O) operation is ready.The I/O devices interrupt the data which is available and does the remaining process; like that interrupts are useful. If interrupts are not present, the CPU needs to be in ... Read More

Inter-process communication is a technique of exchanging data between two or more processes for performing some action on that data. These processes may be present on the same computer or at remote locations.The reasons for Inter-process communication are as follows −Sharing information between processesSpeed up the computation of some processIncreasing the modularity in the applicationNow, let us learn about the type of inter-process communication implemented in the following OS.AndroidAndroid OS uses the following method for sharing data between two or more processes.BindersIt is one of the ways of passing data between processes in the android operating system. The communication between ... Read More

Components of UNIXGenerally, a computer system consists of four main components, called hardware, application programs, operating system, and users.Hardware − Physical devices are nothing but which we can touch and feel.Operating system − It allows the user to communicate with the hardware.Application − There are software programs which give some functionality to the user.User − One who gives instructions to the computer to perform an operation and accepts the result from the computer.If there is no hardware, the system does not have computing capability.If there is no operating system, the user cannot connect to the hardware parts to perform the ... Read More

A modern computer consists of the following −One or more processorsMain memoryDisksPrintersVarious input/output devices.So, to manage all these components, we require a layer of software in the computer system, that layer we call the Operating System (OS).An Operating System is a program that acts as an intermediary or interface between a user of a computer and the computer hardware.It is the most important type of system software in computer systems. Without an operating system the user cannot run application programs on the computer system.Given below is the structure of an operating system −The operating system acts like a government in ... Read More

Message Passing provides a mechanism to allow processes to communicate and to synchronize their actions without sharing the same address space.For example − chat programs on World Wide Web.Now let us discuss the message passing step by step.Step 1 − Message passing provides two operations which are as follows −Send messageReceive messageMessages sent by a process can be either fixed or variable size.Step 2 − For fixed size messages the system level implementation is straight forward. It makes the task of programming more difficult.Step 3 − The variable sized messages require a more system level implementation but the programming task becomes simpler.Step ... Read More

Inter process communication requires communicating to establish a shared memory region. A shared memory region is present in the address space for the process that creates the shared memory segment. And other processes are communicating using a shared memory segment that is attaching it to their address space.Operating system prevents one process from accessing another process’s memory.In shared memory two or more processes can exchange information by reading and writing data in shared memory areas. The processes are also responsible for ensuring that they are not writing to save location.Producer-consumer problemNow, let us discuss producer-consumer process problems.Step 1 − A ... Read More

Shared memory system is the fundamental model of inter process communication. In a shared memory system, in the address space region the cooperating communicate with each other by establishing the shared memory region.Shared memory concept works on fastest inter process communication.If the process wants to initiate the communication and it has some data to share, then establish the shared memory region in its address space. After that, another process wants to communicate and tries to read the shared data, and must attach itself to the initiating process’s shared address space.Let us see the working condition of the shared memory system ... Read More

When the user wants to give an instruction to the OS then it will do it through system calls. Or a user program can access the kernel which is a part of the OS through system calls.It is a programmatic way in which a computer program requests a service from the kernel of the operating system.Program executes in two modes, which are as follows −User mode − Cannot access any hardware resources, which perform only the user operations.Kernel mode − Can access hardware resources like RAM, Printer.The processor in a computer switches between the two modes depending upon what types ... Read More

A process can create several new processes through creating process system calls during the process execution. Creating a process we call it the parent process and the new process is a child process.Every new process creates another process forming a tree-like structure. It can be identified with a unique process identifier that usually represents it as pid which is typically an integer number. Every process needs some resources like CPU time, memory, file, I/O devices to accomplish.Whenever a process creates a sub process, and may be each sub process is able to obtain its resources directly from the operating system ... Read More