An indexer factory function should set values for at least the following in the parameter block before returning control to Directory Server:
SLAPI_PLUGIN_DESTROY_FN, a pointer to the indexer object destructor
SLAPI_PLUGIN_MR_INDEX_FN, a pointer to the indexer
SLAPI_PLUGIN_OBJECT, a pointer to the indexer object
Refer to Chapter 18, Parameter Block Reference for details about the parameter block.