如何使用sed [duplicate]用“：”替换文本

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• Replace a text with a variable [duplicate] 1 answer

用变量[duplicate] 1 answer替换文本

I am trying to replace a text with the help of sed but I am really puzzled about in finding the reason for failure.

我试图在sed的帮助下替换文本,但我真的很困惑在找到失败的原因。

    Main file
    ===========
    user@shell>cat test
    new=21:58:22
    old=09:58:22

    echo $new
    echo $old

    user@shell>sed -i 's/$old/$new/g' yoo
    user@shell>
    user@shell>
    desired output
    ==============
    user@shell>cat yoo
    09:58:22
    09:58:22
    09:58:2209:58:22
    09:58:2209:58:22
    asdasd
    user@shell>

After this I was assuming that I will get the new values in file yoo but no changes are reflection.

在此之后,我假设我将在文件yoo中获取新值,但没有更改是反射。

1 个解决方案

#1

You need to expand the variables using double quotes like this,

你需要使用这样的双引号来扩展变量,

sed -i "s/$old/$new/g" yoo