REG_UNLOAD_KEY_INFORMATION structure (wdm.h)

The REG_UNLOAD_KEY_INFORMATION structure contains information that a driver's RegistryCallback routine can use when a registry hive is unloaded.

Syntax

typedef struct _REG_UNLOAD_KEY_INFORMATION {
  PVOID Object;
  PVOID UserEvent;
  PVOID CallContext;
  PVOID ObjectContext;
  PVOID Reserved;
} REG_UNLOAD_KEY_INFORMATION, *PREG_UNLOAD_KEY_INFORMATION;

Members

Object

A pointer to a registry key object. This object represents the root key of the hive that is being unloaded.

UserEvent

A pointer to an event object.

CallContext

Optional driver-defined context information that the driver's RegistryCallback routine can supply. This member is defined starting with Windows Vista.

ObjectContext

A pointer to driver-defined context information that the driver has associated with a registry object by calling CmSetCallbackObjectContext. This member is defined starting with Windows Vista.

Reserved

This member is reserved for future use. This member is defined starting with Windows Vista.

Remarks

This structure is used by the RegistryCallback routine. When the Argument1 parameter to the RegistryCallback routine is RegNtPreUnloadKey, the Argument2 parameter is a pointer to a REG_UNLOAD_KEY_INFORMATION structure.

The operating system passes the REG_UNLOAD_KEY_INFORMATION structure to the RegistryCallback routine every time a thread attempts to unload a key—for example, when a user-mode thread calls the RegUnloadKey function. In response to a RegNtPreUnloadKey notification, the RegistryCallback routine should free any resources the driver previously allocated for use with the hive before the hive is unloaded.

For more information about registry filtering operations, see Filtering Registry Calls.

Requirements

See also

CmSetCallbackObjectContext

RegistryCallback