Field Width Specifiers

%n

Field width is set to the specified decimal value.

%?

Field width is set to the maximum width of a hexadecimal pointer value. This is 8 in an ILP32 environment, and 16 in an LP64 environment.

%*

Field width is set to the value specified at the current position in the argument list. This value is assumed to be an int. Note that in the 64-bit compilation environment, it may be necessary to cast long values to int.