Linux 用字符串替换文本文件中的第一行
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Replace the first line in a text file by a string
提问by Rookie
I am a newbie at shell scripting, and am confused about how to use sedor any other tools to replace the first line in my text file by a string. Here are the text file contents:
我是 shell 脚本的新手，对如何使用sed或任何其他工具将文本文件中的第一行替换为字符串感到困惑。以下是文本文件内容：
/home/snehil/Desktop/j1/movie.MOV "spome other text lines'
I want to replace the first line (movie file path) with just movie.MOV(could be a variable in the shell script)
我想用just movie.MOV（可能是shell脚本中的变量）替换第一行（电影文件路径）
Please guide me how to do this. I came across sedin some posts, do I need to use sedhere?
请指导我如何做到这一点。我sed在一些帖子中遇到过，我需要在sed这里使用吗？
采纳答案by Gilles Quenot
sed is the right tool, try doing :
sed 是正确的工具，请尝试执行以下操作：
var="movie.MOV"
sed -i "1s/.*/$var/" file.txt
explanations
解释
1mean first line- the rest is the substitution
s///: we substitute everything (.*) by the$varvariable
1平均第一行- 剩下的就是替换
s///：我们用$var变量替换所有内容 (.*)
