How to merge every two lines into one from the command line?

Question

I have a text file with the following format. The first line is the \"KEY\" and the second line is the \"VALUE\".

KEY 4048:1736 string
3
KEY 0:1772 string
1         


        

Answer 1

Try the following line:

while read line1; do read line2; echo "$line1 $line2"; done new_file

Put delimiter in-between

"$line1 $line2";

e.g. if the delimiter is |, then:

"$line1|$line2";