Operating System 操作系统 / 作业系统 重要问答笔记（陆续更新中，2024/04/18周四，已更新）

• 2024/02/28周三，已更新

Q1: What is the purpose of an interrupt in an operating system？
Ans: An interrupt is a signal emitted by a device attached to a computer or from a program within the computer. It requires the operating system (OS) to stop and figure out what to do next. An interrupt temporarily stops or terminates a service or a current process. Interrupts in an operating system serve several important purposes. They allow the operating system to respond to asynchronous events, such as hardware signals or software exceptions, without requiring constant polling. This helps improve system efficiency and responsiveness. Interrupts also enable the operating system to handle multitasking by allowing it to temporarily suspend the execution of one process in favor of another. Additionally, interrupts facilitate communication between the operating system and hardware devices, allowing for efficient data transfer and control. Overall, interrupts play a crucial role in the functioning of an operating system by enabling it to manage and respond to various events and tasks in a timely manner.

问1：操作系统中中断的目的是什么？
答： 中断是由连接到计算机的设备或计算机内的程序发出的信号。它要求操作系统 (OS) 停下来并弄清楚下一步该做什么。中断会暂时停止或终止服务或当前进程。操作系统中的中断有几个重要的用途。它们允许操作系统响应异步事件，例如硬件信号或软件异常，而无需不断轮询。这有助于提高系统效率和响应能力。中断还允许操作系统暂时挂起一个进程的执行以支持另一个进程，从而使操作系统能够处理多任务。此外，中断促进操作系统和硬件设备之间的通信，从而实现高效的数据传输和控制。总的来说，中断在操作系统的功能中起着至关重要的作用，它使操作系统能够及时管理和响应各种事件和任务。

Q2：How does an interrupt differ from a trap？
Ans： There are two kinds of events: traps and interrupts. The difference between a trap and an interrupt is that a trap is triggered by a user program to invoke OS functionality. Still, an interrupt is triggered by a hardware device to allow the processor to execute the corresponding interrupt handler routine.

问2：中断与陷阱有何不同？
答： 有两种事件：陷阱和中断。陷阱和中断之间的区别在于陷阱是由用户程序触发以调用操作系统功能的。尽管如此，中断还是由硬件设备触发，以允许处理器执行相应的中断处理程序例程。

Q3: Can traps be generated intentionally by a user program？if so，for what purpose？
Ans： A trap can be generated intentionally by a user program. It can be used to call operating syste