Processes concepts

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In computing, a process is an instance of a program that is currently executing. A process is a fundamental concept in operating systems, and is responsible for executing code, accessing system resources, and managing threads.

Each process has its own memory space, which is used to store program code, data, and stack frames for executing functions. Processes also have their own set of system resources, such as file handles and network connections.

Processes are managed by the operating system's process scheduler, which determines when each process is allowed to execute and for how long. The scheduler uses various algorithms to allocate CPU time to each process, and may also prioritize certain processes over others.

Processes can communicate with each other through various mechanisms, such as inter-process communication (IPC), shared memory, and message passing. Processes can also spawn child processes, which can be used to perform parallel or distributed processing.

Here are some key concepts related to processes:

  • Process ID (PID): Each process is assigned a unique identifier by the operating system, called a PID. This can be used to identify and manage processes.

  • Process state: Each process has a state, which indicates whether it is currently executing, waiting for input/output (I/O), or blocked on some other operation.

  • Process hierarchy: Processes can be organized into a hierarchical structure, where each process can have one or more child processes. This is often used to implement multi-process or multi-threaded applications.

  • Context switching: When the operating system switches between processes, it must save and restore the context of each process. This includes the program counter, stack pointer, and other register values.

  • Process termination: Processes can be terminated by the operating system, by the user, or by the process itself. When a process is terminated, its resources are released and its memory space is deallocated.

Processes are a critical concept in modern computing, and are used extensively in operating systems, servers, and applications. Understanding how processes work is essential for building efficient, scalable, and reliable software

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