Linux UNIX yes 命令重复输出y

逃离我推掉我的手 2023-10-18 19:36 87阅读 0赞

On [Unix-like][] operating systems, the **yes** command is used to output "**y**", continually, until it is aborted.

This document covers the [GNU][]/[Linux][] version of **yes**.

*  [Description][]
 *  [Syntax][]
 *  [Examples][]
 *  [Related commands][]
 *  [Linux commands help][]

### Description ###

The **yes** command outputs the same [string][], *STRING*, in a constant stream. If *STRING* is not specified, the word it repeats is "**y**".

**yes** dates back to a time before [Unix][] commands included the "force" (**-f**) option, which for many commands is the same as answering "yes" to all [prompts][].

**yes** can be used to do something very similar: if the output of **yes** is [piped][] to a command, it will effectively answer "yes" to any confirmation prompts.

### Syntax ###

yes [STRING]...

yes [OPTION]

### Options ###

<table> 
 <tbody> 
  <tr> 
   <td><strong>--help</strong></td> 
   <td>Display a help message, and exit.</td> 
  </tr> 
  <tr> 
   <td><strong>--version</strong></td> 
   <td>Display version information, and exit.</td> 
  </tr> 
 </tbody> 
</table>

### Examples ###

yes | rm -i *.txt

[Removes][] all files with the [extension][] **.txt** from the [current directory][]. Here, **yes** outputs a constant stream of "**y**" [characters][], and that output is piped to the **rm -i** command, which prompts for confirmation before deleting each file. The **y** characters from the **yes** command will respond "yes" to each prompt automatically.

yes n | rm -i *.txt

Here, the **yes** command outputs "**n**" in a constant stream to the **rm -i**command, answering "no" to all the same questions. Therefore, this command deletes no files.

[Unix-like]: https://www.computerhope.com/jargon/u/unix-like.htm
[GNU]: https://www.computerhope.com/jargon/g/gnu.htm
[Linux]: https://www.computerhope.com/jargon/l/linux.htm
[Description]: https://www.computerhope.com/unix/yes.htm#desc
[Syntax]: https://www.computerhope.com/unix/yes.htm#syntax
[Examples]: https://www.computerhope.com/unix/yes.htm#examples
[Related commands]: https://www.computerhope.com/unix/yes.htm#related
[Linux commands help]: https://www.computerhope.com/unix.htm
[string]: https://www.computerhope.com/jargon/s/string.htm
[Unix]: https://www.computerhope.com/jargon/u/unix.htm
[prompts]: https://www.computerhope.com/jargon/p/prompt.htm
[piped]: https://www.computerhope.com/jargon/p/pipe.htm
[Removes]: https://www.computerhope.com/unix/urm.htm
[extension]: https://www.computerhope.com/jargon/e/extensio.htm
[current directory]: https://www.computerhope.com/jargon/c/currentd.htm
[characters]: https://www.computerhope.com/jargon/c/charact.htm