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Feedback on SimConnect_SetDataOnSimObject()

Almost all calls in SimConnect have two or three ways in which they can return a result to the caller:
  • The call itself can fail, which generally means that required values are missing or wildly incorrect. An obvious example is an incorrect HANDLE.
  • The call can fail validation by the simulator, resulting in an exception message. This is always linked to a "SendID", which has to be queried after performing the call. Why it is not returned always is a mystery to me, because zero or negative values are errors, so positive values could have been used as success marker and SendID in one.
  • Depending on the call, a reply message (or stream of messages) comes in, generally using a RequestID.
That said, there one glaring exception: If you call SetDataOnSimObject, there is no way to know if it succeeded other than waiting a bit, or querying back the same data and see if it changed.

Any ideas on what the best approach is here? If possible I'd like the call to end when I know no exceptions have been returned, but that means either a delay, which flies against all principles (because... for how long?), or else spend that extra call and wait for the (changed) data.

There is no other method. You set the value and then next cycle check to see it's been updated to your value.