How to add a string to a specific line in a file using sed?

Question

I have the following file test.txt

node1
node2
node3
node4

I want to add the string "1" next to it after a space next to the word node2 using sed so it looks like this.

node1
node2 1
node3
node4

I tried sed '/node2/a 1' test.txt but it adds a new line. How do I just add a space followed by a 1.

Barmar · Accepted Answer · 2020-05-22 00:05:39Z

2

a is for adding new lines. Use s to modify the line in place.

sed '/node2/s/$/ 1/' test.txt

answered May 22, 2020 at 0:05

Barmar

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2 Comments

this is perfect, if you dont mind could you take a look at stackoverflow.com/questions/61945793/…

You need to make some attempt to solve the problem yourself. awk would be easier for that problem.