# Description Rework FileTransfer (currently in samples) to make it a generic S2OPC server module. ## Code version identification 0c251792b8a8b7a0794459464e14ee725caadbb3 ## Current behavior Sample (toolkit_demo_file_transfer.c) using internal file storage (with certain limitations). ## Expected behavior Generic toolkit for OPC UA file transfer functionality. The main change is to replace the file's internal storage mode (during all processes): File (before) -> Byte string (after enhancement) # Security impact - None # Implementation - Internal storage : ByteString - User Cb: on open and close methods (offers the user the possibility of downloading/saving content in a hard file on their own. -> New API on server_wrapper: _libs2opc_file_transfer.h_ -> New sample (using this API): _toolkit_demo_file_transfer_new.c_ Limitations : - Allows only one simultaneous opening per file. - A file handle remains valid on close session (standard OPC UA deviation). - UserWritable variable are not supported (initialize to `true` at the first open method call, when Writable variable is not defined) The next steps will be addressed in the ticket #1690