typedef SilcUInt8 SilcAttribute;

    The SilcAttribute type definition and the attributes. The attributes
    listed here are the official attributes defined in the internet
    draft.  They define the contents of the attribute payload and the
    type of the attribute.

    typedef SilcUInt8 SilcAttribute;
    
    /* All defined attributes.  See the specs for detailed information.  The
       comment is the structure or data type that must be used with the
       silc_attribute_get_object function to fetch parsed attribute. */
    #define SILC_ATTRIBUTE_NONE                   0
    #define SILC_ATTRIBUTE_USER_INFO              1   /* SilcVCard */
    #define SILC_ATTRIBUTE_SERVICE                2   /* SilcAttributeObjService */
    #define SILC_ATTRIBUTE_STATUS_MOOD            3   /* SilcAttributeMood */
    #define SILC_ATTRIBUTE_STATUS_FREETEXT        4   /* char * (UTF-8 string) */
    #define SILC_ATTRIBUTE_STATUS_MESSAGE         5   /* SilcMime */
    #define SILC_ATTRIBUTE_PREFERRED_LANGUAGE     6   /* char * (UTF-8 string) */
    #define SILC_ATTRIBUTE_PREFERRED_CONTACT      7   /* SilcAttributeContact */
    #define SILC_ATTRIBUTE_TIMEZONE               8   /* char * (UTF-8 string) */
    #define SILC_ATTRIBUTE_GEOLOCATION            9   /* SilcAttributeObjGeo */
    #define SILC_ATTRIBUTE_DEVICE_INFO            10  /* SilcAttributeObjDevice */
    #define SILC_ATTRIBUTE_EXTENSION              11  /* SilcMime */
    #define SILC_ATTRIBUTE_USER_PUBLIC_KEY        12  /* SilcAttributeObjPk */
    #define SILC_ATTRIBUTE_SERVER_PUBLIC_KEY      13  /* SilcAttributeObjPk */
    #define SILC_ATTRIBUTE_USER_DIGITAL_SIGNATURE 14  /* SilcAttributeObjPk */
    #define SILC_ATTRIBUTE_SERVER_DIGITAL_SIGNATURE 15 /* SilcAttributeObjPk */
    #define SILC_ATTRIBUTE_USER_ICON              16  /* SilcMime */
    #define SILC_ATTRIBUTE_PHONE_NUMBER           17  /* SilcAttributeObjPN */