H5I_GET_FILE_ID returns the identifier of the file associated with the object referenced by
Note that the HDF5 library permits an application to close a file while objects within the file remain open. If the file containing the object
obj_id is still open, H5I_GET_FILE_ID will retrieve the existing file identifier. If there is no existing file identifier for the file, i.e., the file has been closed, H5I_GET_FILE_ID will reopen the file and return a new file identifier. In either case, the file identifier must eventually be released using H5F_CLOSE.