回声产出的bash脚本-e参数。我怎样才能prevent呢？ [英] echo outputs -e parameter in bash scripts. How can I prevent this?

问题描述

我读过回声手册页，它告诉我，-e参数将允许转义字符，如换行符转义N，有其特殊的意义。当我键入​​命令

I've read the man pages on echo, and it tells me that the -e parameter will allow an escaped character, such as an escaped n for newline, to have its special meaning. When I type the command

$ echo -e 'foo\nbar'

到交互式bash shell中，我得到预期的输出结果：

into an interactive bash shell, I get the expected output:

foo
bar

但是当我使用这个相同的命令（我试过的字符作为测试情况下，这个命令字符）我得到以下的输出：

But when I use this same command (i've tried this command character for character as a test case) I get the following output:

-e foo
 bar

这是因为如果回声间pretting的-e作为参数（因为新行仍显示），但它也跨$ P $点的-e作为一个字符串呼应。这里发生了什么？我怎样才能prevent显示了-e？

It's as if echo is interpretting the -e as a parameter (because the newline still shows up) yet also it interprets the -e as a string to echo. What's going on here? How can I prevent the -e showing up?

推荐答案

您需要使用＃！/斌/庆典在你的脚本的第一行。如果你不这样做，或者如果您使用＃！/ bin / sh的，该脚本将由Bourne shell和它的回声不承认 -e 选项。一般情况下，建议所有新脚本中使用的printf 而不是回声如果便携性是非常重要的。

You need to use #!/bin/bash as the first line in your script. If you don't, or if you use #!/bin/sh, the script will be run by the Bourne shell and its echo doesn't recognize the -e option. In general, it is recommended that all new scripts use printf instead of echo if portability is important.

在Ubuntu中， SH 是一个符号链接提供的 /斌/破折号。

In Ubuntu, sh is provided by a symlink to /bin/dash.

这篇关于回声产出的bash脚本-e参数。我怎样才能prevent呢？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！