The in-use list provides the object with information such as:
All objects that the user interacts with are actually just records that have been inserted into a container control. A container is an object, such as a folder, which also has an in-use list. Because of the close relationship between an object's in-use list and container objects, this chapter includes a description of methods that are relevant to container usage as well as object usage. Object Usage methods, as shown in the following table, allow an object to keep track of its resources and how it is being used:
旼컴컴컴컴컴컴컴컴컴컴컴컴쩡컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴엿Method Name 쿏escription � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pAddToObjUseList 쿌dds an object to the list of � � 쿽bjects in use by the object. � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pAssertObjectMutexSem 쿟his instance method verifies that � � 쿪n object's mutex semaphore is held� � 쿯or the current thread. � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pCnrDeleteUseItem 쿏eletes the object's USAGE_RECORD � � 퀅se-item for the specified � � 쿬ontainer. � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pDeleteFromObjUseList 쿏eletes an object from the list of � � 쿽bjects in use by the object. � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pFindUseItem 쿝etrieves an object from the list � � 쿽f objects in use by the object. � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pFindViewItem 쿝etrieves a USAGE_OPENVIEW item � � 쿯rom the list of items in use by � � 퀃he object. � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pIsLocked 쿟ells you whether the object is � � 쿹ocked or not. � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pLockObject 쿔ncreases the lock counter for the � � 쿽bject. Objects that are locked � � 퀇ill not be made dormant. � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pReleaseObjectMutexSem 쿝eleases the mutex semaphore for an� � 쿽bject. Each object has associated � � 퀇ith it a mutex semaphore that can � � 쿫e used to serialize access to � � 퀁esources. � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pRequestObjectMutexSem 쿝equests the mutex semaphore for an� � 쿽bject. Each object has associated � � 퀇ith it a mutex semaphore that can � � 쿫e used to serialize access to � � 퀁esources. � 쳐컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 퀇pUnlockObject 쿢nlocks the object so that it can � � 쿫e made dormant. � 읕컴컴컴컴컴컴컴컴컴컴컴컴좔컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
The in-use list is a linked list of USEITEM data structures. It consists of an item type and a pointer to the next USEITEM data structure, immediately followed by an item type-specific data structure. The types of items that can be added to an object's in-use list and the type-specific data structures that follow each USEITEM data structure are shown in the following table:
旼컴컴컴컴컴컴컴쩡컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커 쿔tem 쿞tructure 쿏escription � 쳐컴컴컴컴컴컴컴탠컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑 쿢SAGE_LINK 쿗INKITEM 쿌 shadow of the object has been � � � 쿪wakened. � 쳐컴컴컴컴컴컴컴탠컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑 쿢SAGE_MEMORY 쿘EMORYITEM쿘emory has been allocated by � � � 퀇pAllocMem. � 쳐컴컴컴컴컴컴컴탠컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑 쿢SAGE_OPENFILE 쿣IEWFILE 쿟he object (if a data file) has � � � 쿫een opened. � 쳐컴컴컴컴컴컴컴탠컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑 쿢SAGE_OPENVIEW 쿣IEWITEM 쿌 view of the object has been � � � 쿽pened. � 쳐컴컴컴컴컴컴컴탠컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑 쿢SAGE_RECORD 쿝ECORDITEM쿟he object has been inserted into a� � � 쿬ontainer window. � 읕컴컴컴컴컴컴컴좔컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸