ICLRTask::Reset Method

Informs the common language runtime (CLR) that the host has completed a task, and enables the CLR to reuse the current ICLRTask instance to represent another task.


HRESULT Reset (  
    [in] BOOL fFull  


[in] true, if the runtime should reset all thread-related static values in addition to the security and locale information related to the current ICLRTask instance; otherwise, false.

If the value is true, the runtime resets data that was stored using AllocateDataSlot or AllocateNamedDataSlot.

Return Value

HRESULT Description
S_OK Reset returned successfully.
HOST_E_CLRNOTAVAILABLE The CLR has not been loaded into a process, or the CLR is in a state in which it cannot run managed code or process the call. successfully
HOST_E_TIMEOUT The call timed out.
HOST_E_NOT_OWNER The caller does not own the lock.
HOST_E_ABANDONED An event was canceled while a blocked thread or fiber was waiting on it.
E_FAIL An unknown catastrophic failure occurred. When a method returns E_FAIL, the CLR is no longer usable within the process. Subsequent calls to hosting methods return HOST_E_CLRNOTAVAILABLE.


The CLR can recycle previously created ICLRTask instances to avoid the overhead of repeatedly creating new instances every time it needs a fresh task. The host enables this feature by calling ICLRTask::Reset instead of ICLRTask::ExitTask when it has completed a task. The following list summarizes the normal life cycle of an ICLRTask instance:

  1. The runtime creates a new ICLRTask instance.

  2. The runtime calls IHostTaskManager::GetCurrentTask to get a reference to the current host task.

  3. The runtime calls IHostTask::SetCLRTask to associate the new instance with the host task.

  4. The task executes and completes.

  5. The host destroys the task by calling ICLRTask::ExitTask.

Reset alters this scenario in two ways. In step 5 above, the host calls Reset to reset the task to a clean state, and then decouples the ICLRTask instance from its associated IHostTask instance. If desired, the host can also cache the IHostTask instance for reuse. In step 1 above, the runtime pulls a recycled ICLRTask from the cache instead of creating a new instance.

This approach works well when the host also has a pool of reusable worker tasks. When the host destroys one of its IHostTask instances, it destroys the corresponding ICLRTask by calling ExitTask.


Platforms: See System Requirements.

Header: MSCorEE.h

Library: Included as a resource in MSCorEE.dll

.NET Framework Versions: Available since 2.0

See Also

ICLRTask Interface
ICLRTaskManager Interface
IHostTask Interface
IHostTaskManager Interface