> For the complete documentation index, see [llms.txt](https://book.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.bsdcn.org/man/man9/devclass.9.md).

# devclass.9

`devclass` — 表示一类设备的对象

## 名称

`devclass`

## 概要

```c
typedef struct devclass *devclass_t;
```

## 描述

`devclass` 对象在系统中有两个主要功能。第一是管理设备实例的单元号分配，第二是保存特定总线类型的设备驱动程序列表。每个 `devclass` 都有一个名称，并且不能有两个同名的 devclass。这确保了向设备实例分配唯一的单元号。所有同名实例都被视为相同。

当不需要特定单元号时，使用 `DEVICE_UNIT_ANY`。

## 参见

[devclass\_add\_driver(9)](https://github.com/FreeBSD-Ask/freebsd-man-sc/tree/main/man9/devclass_add_driver.9.md), [devclass\_delete\_driver(9)](https://github.com/FreeBSD-Ask/freebsd-man-sc/tree/main/man9/devclass_delete_driver.9.md), [devclass\_find(9)](/man/man9/devclass_find.9.md), [devclass\_find\_driver(9)](https://github.com/FreeBSD-Ask/freebsd-man-sc/tree/main/man9/devclass_find_driver.9.md), [devclass\_get\_device(9)](/man/man9/devclass_get_device.9.md), [devclass\_get\_devices(9)](/man/man9/devclass_get_devices.9.md), [devclass\_get\_maxunit(9)](/man/man9/devclass_get_maxunit.9.md), [devclass\_get\_name(9)](/man/man9/devclass_get_name.9.md), [devclass\_get\_softc(9)](/man/man9/devclass_get_softc.9.md), [device(9)](/man/man9/device.9.md), [driver(9)](/man/man9/driver.9.md)

## 作者

本手册页面由 Doug Rabson 编写。


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