Question

This is not a question about appending a new line of text to a file; it’s about appending data to each row.

I have over 300 lines in a CSV file, and I want to add more text to each line separated with commas (a format used for MS Excel charts).

From the ex.txt file:

12:11, 321
12:12, 23

I want to append more fields to each line, like this:

12:11, 321, 222, 55
12:12, 23, 33, 402

Answer 1

 while read line; do
     # modify $whatYouWantToAppend
     echo -e "${line} ${whatYouWantToAppend}\n" >> newTest.txt
 done < test.txt