The ‘%m’ and ‘%d’ directives support the ‘#’, ‘0’ and ‘+’ flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include
‘G’, ‘U’, ‘b’, ‘D’, ‘k’ and ‘n’.
All fields support the format flag ‘-’, which makes fields left-aligned. That is, if the field width is greater than the actual contents of the field, the requisite number of spaces are printed after the field content instead of before it.