# 3.11.设备和设备节点

设备是一个主要用于描述系统中与硬件相关活动的术语，包括磁盘、打印机、显卡和键盘。当 FreeBSD 启动时，大多数启动消息都与设备的检测有关。启动消息的副本会保存到 `/var/run/dmesg.boot` 文件中。

每个设备都有一个设备名称和编号。例如，`ada0` 是第一个 SATA 硬盘，而 `kbd0` 表示键盘。

FreeBSD 中的大多数设备必须通过名为设备节点的特殊文件访问，这些文件位于 `/dev` 目录中。


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