bash 由于用空格扩展变量导致的 Grep 错误

Grep error due to expanding variables with spaces

提问by nightfire

I have a file called "physics 1b.sh". In bash, if I try

我有一个名为“ physics 1b.sh”的文件。在 bash 中，如果我尝试

x="physics 1b"
grep "string" "$x".sh

grep complains:

grep 抱怨：

grep:  physics 1b: No such file or directory.

However, when I do

但是，当我这样做时

grep "string" physics\ 1b.sh 

It works fine. So I guess the problem is something to do with the variable not being expanded to include the backslash that grep needs to recognize the space. How do I get this to work?

它工作正常。所以我猜这个问题与变量没有被扩展以包含 grep 需要识别空间的反斜杠有关。我如何让这个工作？

Using bash 3.2, mac os 10.6.

使用 bash 3.2，mac os 10.6。

Edit:
Never mind, the problem was that x was set to " physics 1b", but when I did echo $xto check the contents, bash chopped off the spaces in the front so I couldn't tell that it was different. The first way above actually works.

编辑：
没关系，问题是 x 被设置为" physics 1b"，但是当我 echo $x检查内容时，bash 切掉了前面的空格，所以我看不出它有什么不同。上面的第一种方法确实有效。

回答by Marcelo Cantos

Put the entire argument in double-quotes:

将整个论点放在双引号中：

grep "string" "$x.sh"

回答by Vijay

use this in your script.

在您的脚本中使用它。

grep "string" "${x}.sh"

回答by ghostdog74

another way

其它的办法

grep "string" "${x}.sh"