audit_trail_log()[audit_trail_log_opt()]<optional> audit_trail_log_opt()={type,atl_type()}|{dir,atl_dir
数据类型 oid()=[byte()]atl_type()=read|write|read_writenotification_delivery_info()=#snmpa_notification_delivery_info
,error_index(),varbinds()}error_status()=noError|atom()error_index()=integer()varbinds()=[varbind()]atl_type