* @throws SmbException
     */
    synchronized SmbFileHandleImpl ensureOpen () throws CIFSException {
        // ensure file is open
        if ( this.handle == null || !this.handle.isValid() ) {
            // one extra acquire to keep this open till the stream is released
            this.handle = this.file.openUnshared(this.openFlags, this.access, this.sharing, SmbConstants.ATTR_NORMAL, this.options).acquire();
            return this.handle;

        policy with `tf.data.experimental.service.ShardingPolicy` enum. It can
        be one of `OFF` (equivalent to today's `"parallel_epochs"` mode),
        `DYNAMIC` (equivalent to today's `"distributed_epoch"` mode), or one of
        the static sharding policies: `FILE`, `DATA`, `FILE_OR_DATA`, or `HINT`
        (corresponding to values of `tf.data.experimental.AutoShardPolicy`).

          include a readable copy of the attribution notices contained
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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *

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