[netcdfgroup] Concurrent read/write by two different applications: one writes, other reads

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• Subject: [netcdfgroup] Concurrent read/write by two different applications: one writes, other reads
• From: "Blaise, Sebastien" <s.blaise@xxxxxxxxx>
• Date: Mon, 29 Apr 2019 11:03:51 +0000
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Hi,

On Windows, I develop a C++ software engine doing calculations, writing the 
results as time series in a netcdf4 file (time is a NC_UNLIMITED dimension). 
The engine only writes, no read.

I have a C# based GUI loading the netcdf4 file and checking if a new time 
snapshot is completely written by the engine. Then it loads this snapshot for 
real-time visualization. The GUI only reads, no write.

I am currently using netcdf4, but it results in segmentation faults when the 
engine and GUI concurrently work on the same dataset. I believe it is because 
netcdf4 is not thread-safe, although I am not sure of what it involves exactly.

However, as I am not doing any parallel read or write, and each process 
performs a single type of operation, I wonder if there is a simple way of doing 
this safely using netcdf4. Is it possible, or should I use hdf5 directly?

Thanks