> 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/man4/ng_echo.4.md).

# ng\_echo.4

`ng_echo` — netgraph 回显节点类型

## 名称

`ng_echo`

## 概要

`#include <netgraph/ng_echo.h>`

## 描述

`echo` 节点类型将所有数据和控制消息反射回发送者。此节点类型用于测试和调试。

## 钩子

`echo` 节点接受任何连接请求，无论钩子名如何，只要名称唯一即可。

## 控制消息

此节点类型仅支持通用控制消息。任何其他控制消息都会被反射回发送者。

## 关闭

此节点在收到 `NGM_SHUTDOWN` 控制消息时，或当所有钩子都已断开时关闭。

## 参见

[netgraph(4)](/man/man4/netgraph.4.md), [ng\_hole(4)](/man/man4/ng_hole.4.md), ngctl(8)

## 历史

`echo` 节点类型实现于 FreeBSD 4.0。

## 作者

Julian Elischer <julian@FreeBSD.org>


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