How to insert a line at the beginning of a file

To insert a line at the beginning of a file, we can use sed to achieve this task. By using in-place editing -i, we can instruct sed to make a change to an existing file. The next step is to tell sed what to change or insert and at what place.

sed -i '1i # New first line' mytextfile.txt

Explanation

• -i = inline file edit
• 1i = insert at first line
• # New first line = Text to add