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Hello, I've been using Snap7 library for a while in the client role, so I can communicate with SIEMENS PLCs There is specific LabVIEW info here: http://snap7.sourceforge.net/labview.html I can successfully use the Cli VIs to read/write from PLCs DBs (a DB is just a memory block). For reading I pre-allocate a buffer, but I'm not sure if I'm doing it properly. My main concern is about memory leakage, I don't know if the memory will be freed after the VI exits or it will not be freed as long as the VI is in memory. Attached is what I have just now for reading. I define a typedef for each DB, it is a cluster of booleans, and reserve memory according to the number of booleans, but always in multiple of 8 (I read only bytes). I request the data with the CliDBRead and after that I make some conversions to return the data in a variant that I later cast to the proper typedef. Can you tell me if this is the best way to do this? Thank you!