> 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/man5/fbtab.5.md).

# fbtab.5

`fbtab` — 登录时更改设备保护

## 名称

`fbtab`

## 描述

`fbtab` 文件包含若干行，每行指定一个设备以及与之关联保护的设备列表。注释以 `#` 开始，延续到行尾。

空行或仅含注释的行会被忽略。

所有其他行由三个以空白分隔的字段组成：登录设备（**/dev/ttyv0**）、八进制权限编号（`0600`），以及以冒号（`:`）分隔的设备模式列表（**/dev/console**、**/dev/dsp\***）。所有设备模式均为绝对路径。

如果 tty 参数（相对路径）与某个登录设备名（绝对路径）匹配，则以冒号分隔的列表中各设备的权限将按第二个字段的规定设置，其所有权将更改为 UID 和 GID 参数所指定的值。

## 文件

**`/etc/fbtab`** `fbtab` 文件位于 **/etc**。

## 参见

[login(1)](/man/man1/login.1.md), getty(8)

## 作者

Guido van Rooij


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