> 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/man1/printenv.1.md).

# printenv.1

`printenv` — 打印环境变量

## 名称

`printenv`

## 概要

`printenv [name]`

## 描述

`printenv` 实用程序打印环境中各变量的名称和值，每行一个名称/值对。如果指定了 `name`，则只打印其对应的值。

某些 shell 可能提供内建的 `printenv` 命令，与本实用程序类似或相同。请参阅 [builtin(1)](/man/man1/builtin.1.md) 手册页。

## 退出状态

`printenv` 实用程序成功时退出值为 0，发生错误时大于 0。

## 参见

[csh(1)](https://github.com/FreeBSD-Ask/freebsd-man-sc/blob/main/man1/csh.1.md), [env(1)](/man/man1/env.1.md), [sh(1)](/man/man1/sh.1.md), [environ(7)](https://github.com/FreeBSD-Ask/freebsd-man-sc/blob/main/man7/environ.7.md)

## 标准

`printenv` 实用程序是为了与早期 BSD 和 FreeBSD 版本兼容而保留的，并未被任何标准所规定。`printenv` 的功能可以使用 echo(1) 和 [env(1)](/man/man1/env.1.md) 实用程序来复制实现。

## 历史

`printenv` 命令首次出现于 3.0BSD。


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