- An application calls ClusterResourceControl to initiate a control code operation.
- The resource DLL needs to be notified of a cluster event such as an upgrade.
In both cases, a control code is passed to the resource DLL as an input parameter. The DLL can implement the control code operation, instruct the Resource Monitor to handle the operation, or both.
Some control codes should be handled by the Resource Monitor; others require or benefit from customized implementation in the DLL. To determine how and why to support a particular control code, refer to the individual control code descriptions in Control Codes.
To request that the Resource Monitor process a control code, return ERROR_INVALID_FUNCTION. You can return this value for a control code even if you include support for the code in ResourceControl, allowing you to augment the default functionality of the Resource Monitor.
As with all entry point functions, follow the Recommended Practices for Resource DLLs.