Its as though the arguments I am passing to open aren't being received

I agree, and that's my point.

If very far under the covers, these threads are sharing some common space for performing the atomic openoperation, there could be a race condition where one starts to set up up the parameter block, but before the system call is triggered, another thread goes to update the same block of memory, resulting in invalid parameters being in that space once the service call starts to try to read it.

No doubt one of many possible explanations, but if that's the case, two things come to mind:

1. A workaround involving retries could buy you a quick and effective, if less than completely graceful, solution, and;
2. The correct fix, from an engineering perspective, might involve poring over the code for the threads as well as the I/O modules/features to see if there is a prudent place to establish a semaphore or similar gating mechanism to eliminate the race condition.

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