PK_ERROR_code_t PK_ATTRIB_ask_nth_int
(
--- received arguments ---
PK_ATTRIB_t     attrib,             --- attribute
int             field_no,           --- field number (>= 0)
int             index,              --- index of integer (>= 0)

--- returned arguments ---
int      *const n                   --- nth integer
)


This function returns a single element of the integer array from field
field_no of the given attribute.


Specific Errors:
    PK_ERROR_bad_field_number       The attribute does not have a field with
                                    this number
    PK_ERROR_field_of_wrong_type    The field is not an int field
    PK_ERROR_bad_index              The field has no int with this index