I need to replace the text from File2.txt to File1.txt between 5th and 8th position. It supposed to be any character between 5th and 8th position, I just need to replace with new characters in mentioned position and remaining position character should be same as it is.
abcd9876efghijklmno abcd9676efghijklmno abcd9886efghijklmno abcd9976efghijklmno
1234 4321 6543 5678
abcd1234efghijklmno abcd4321efghijklmno abcd6543efghijklmno abcd5678efghijklmno
Command I tried
sed '/substr($0,5,4)/r File2.txt' File1.txt >file_new.txt