linux - How to duplicate string in bash?

Question

I have the following string in bash

str="kallel"

I want to create from str an str2. The str2 contains str duplicated till the length = 20. So the result should be like this:

str2="kallelkallelkallelka"

How to do in in bash?

Answer 1

This should work:

str="kallel"
str2="${str}"
while (( ${#str2} < 20 ))
do
  str2="${str2}${str}"
done
str2="${str2:0:20}"