Cancelling a thread

I want to send a message to a thread to close and am attempting to use the CBL_THREAD_IDDATA_ALLOC and CBL_THREAD_IDDATA_GET routines. I am am getting an exception error when calling CBL_THREAD_IDDATA_GET after creating the and the intellisense is saying there is no routine with this signature. I was going by the example from the documentation. I then created a new project using the example exactly as written and I get the same error. Is there a bug in this approach?