This is a family of functions which return a specified attribute
value for an Object using one of several different data
types. The type is selected by replacing X in the function name
by C, D, F, I or L, to obtain a result in const char (i.e. string),
double, float, int, or long format, respectively.
If possible, the attribute value is converted to the type you
request. If conversion is not possible, an error will result.