The manual says dataNew deletes the dataset, frees the memory, and if Records & Fields are both 0 does not create a new dataset.

However, this does not appear to be happening. With Records & Fields both 0, memory usage does not decrease (per memory()).

Does anyone else see this memory leak?

If the Zorro.exe process memory footprint does not decrease, this does not imply a memory leak. It's possible the memory is being recycled for the next dataset to increase speed. Heap allocations can be slow.

Thanks AndrewAMD.

Well, it isn't dataNew, but it's very weird. I could copy the failing script to a new file and it would run without problems. Same thing happened with another script. No idea if it's filename length or what. Perhaps a Wine glitch. No time now to copy stuff over to a real Win & try there... For now close this pending further debugging when time allows.

Thanks.