Interrupt handler is a special type of computer program that responds to a hardware or software interrupt signal. An interrupt occurs when a hardware or software process requests the operating system (OS) to pause the current task and execute a different task instead. The interrupt handler then determines what action should be taken in response to the interrupt.
A typical example of an interrupt is when a computer receives an input from the keyboard or mouse. The OS then sends a signal to the interrupt handler, which reads the input and tells the OS which action to take. This might be to launch an application, display a dialog box, or create a new process.
The interrupt handler has to perform a significant number of tasks in order to correctly process the interrupt. First, the interrupt handler has to identify the source of the interrupt, and then decide the best course of action. This could be to invoke a kernel thread or to dispatch a task on the CPU. The interrupt handler also has to update the interrupt table and the device or driver registers if necessary.
The interrupt handler has become a more important part of computer operations as the complexity of operating systems and hardware has increased. Along with other low-level processes, interrupt handlers are now responsible for a great deal of extended functionality. As computers become more adept at multitasking, the interrupt handler is of particular importance. Without interrupt handlers, multitasking operations would be impossible.
