/// <exception cref="System.IO.IOException"></exception>
internal static LocalObjectContainer FreshTempFile(string fileName, int blockSize
)
{
FileStorage storage = new FileStorage();
storage.Delete(fileName);
IConfiguration db4oConfig = DefragmentConfig.VanillaDb4oConfig(blockSize);
db4oConfig.ObjectClass(typeof(IdSlotMapping)).ObjectField("_id").Indexed(true);
db4oConfig.Storage = storage;
return((LocalObjectContainer)Db4oFactory.OpenFile(db4oConfig, fileName).Ext());
}