GetFieldString
int nRetVal = GetFieldString(pFieldName, pUTF16, pBufferCharacters);
GetFieldString(APE_TAG_FIELD_TRACK, cBuffer, &nBufferCharacters);
GetFieldString(APE_TAG_FIELD_GENRE, cBuffer, &nBufferCharacters);
GetFieldString(pFieldName, cBuffer, &nBufferCharacters);
virtual int GetFieldString(const str_utf16 * pFieldName, str_utf16 * pBuffer, int * pBufferCharacters);