Insert Text at Specific Line of File in Linux

Using text editor can be hard to insert text at specific line of a large file because need to scroll to the correct line. We can achieve the same result using the command. This tutorial shows how to do this in Linux.

Create a new file for testing:

printf "Line1\nLine2\nLine4\n" > test.txt

The sed command can be used for text files processing. To insert text at specific line of a file, use the ni modifier, where n is a line number. For example, the following command inserts text at line 3:

sed -i "3i Line3" test.txt

The -i option will edit file in-place.