At the top of the kernel is the system call interface, which handles the routing of user-space calls to their appropriate destination in the kernel (such as an open, read, or write).

内核的顶部是系统调用接口，处理用户空间调用到内核中合适的目的地的路由(例如open、read或write)。

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When you make a telephone call, you're using their network, and you're also making use of the peer agreements they have with other phone networks, while enjoying the use of their routing system.

每当你打电话，你就在使用他们的网络，当你在使用他们的路由系统的时候，同时也在使用移动运营商与其他电话网络之间的协议。

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