%s means print a string argument. Actually, prints any object, with `princ'.
%d means print as signed number in decimal.
-%o means print as unsigned number in octal.
-%x means print as unsigned number in hex.
+%o means print a number in octal. The value of `binary-as-unsigned'
+ determines whether it's printed as signed or unsigned.
+%x means print a number in hex. The value of `binary-as-unsigned'
+ determines whether it's printed as signed or unsigned.
%X is like %x, but uses upper case.
%e means print a number in exponential notation.
%f means print a number in decimal-point notation.