Sometimes we need to insert a line at middle of the existing file. You can add line at specific line number using Linux command line or shell scripts.
In this tutorial, we will discuss about adding a text line at middle of file as specific line number.
Let’s have an example, I have a text file named file1.txt with following content:
cat file1.txt
this is line one
this is line two
this is line three
Now I have to insert text “HelloWorld” at the line number 3. To do this run the following command.
sed -i '3iHelloWorld' file1.txt
Details of Parameters:
- sed: is the command itself.
- -i: : Update content in same file.
- 3: line number where new line will be inserted.
- i: parameter, which told sed to insert line.
- HelloWorld: text to be added.
- file1.txt: is the file in which new line need to add.
Above command will insert the content in file1.txt at line number 3. Let’s check the content of the file:
cat file1.txt
this is line one
this is line two
HelloWorld
this is line three
1 Comment
You also can use -i modifier to edit the file itself without creating an intermediate file
$ sed -i ‘3itecadmin 3’ file1.txt
Moreover, if you are not sure about the changes that will be made, add a suffix to the -i flag that will make a backup of the original file
$ sed -i.bak ‘3itecadmin 3’ file1.txt