Eventsprocesses

Eventsprocesses describes the interaction between events and processes in computing systems. An event is a notification or occurrence that a system can react to, such as a user input, a completed I/O operation, a timer expiry, or a message from another process. A process is an executing program with its own state and resources. The concept emphasizes how events drive the behavior and lifecycle of processes, and how processes generate, respond to, or schedule events.

In event-driven architectures, an event loop allocates control by dispatching handlers in response to events. Processes may be single-threaded workflows or composed of multiple threads or coroutines that run concurrently, each handling different events. Asynchronous I/O, callbacks, futures, and promises are common mechanisms that decouple event generation from processing and allow responsive systems.

From an operating system perspective, events are often delivered as interrupts or signals. The kernel notifies processes of events, or schedules work in response to hardware and software triggers. Event-driven scheduling and reaction to events underlie many system services, including networking stacks and graphical user interfaces. This approach helps manage latency and resource usage by focusing work on the occurrence of events rather than continuous polling.

Applications span graphical interfaces, network servers, real-time monitoring, and middleware. Designing around events and processes involves considerations of latency, throughput, ordering guarantees, error handling, and resource management. Common patterns include event loops, message queues, and reactive streams, which provide structured ways to model the flow of events through processes. The goal is to create systems that respond promptly to events while maintaining correctness and efficiency.