http://kor.i2p/books/The%20C%20Programming%20Language%20by%20K&R/appb.html
The conversion characters d , i , n , o , u , and x may be preceded by h if the argument is a
pointer to short rather than int, or by l (letter ell) if
the argument is a pointer to long . The conversion characters e , f , and g may be preceded by l if a
pointer to double rather than float is in the argument
list, and by L if a pointer to a long double .