Allows other classes to use the same resources. For example, if the reader reads from a file, this method closes the file so that an OIV.LDM.Writers.SoVolumeWriter associated with the same file can re-open it in write mode. The reader remembers the resources that were closed, so they can re-opened by calling OIV.LDM.Readers.SoVolumeReader.RestoreAllHandles().

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