Format column
printf "%-10s %10s %-10s %-10s\n" aaaaa bbbbb ccccc ddddd
# aaaaa bbbbb ccccc ddddd
# printf "width1 width2 width3 width4\n" column1 column2 column3 column4
# '%-Ns' = left justified width N
# '%Ns' = right justified width N