* `write(data)`: Escribe `data` (`str` o `bytes`) en el archivo.
* `read(size)`: Lee `size` (`int`) bytes/caracteres del archivo.
* `seek(offset)`: Va a la posición de bytes `offset` (`int`) en el archivo.
    * Por ejemplo, `await myfile.seek(0)` iría al inicio del archivo.
    * Esto es especialmente útil si ejecutas `await myfile.read()` una vez y luego necesitas leer el contenido nuevamente.
* `close()`: Cierra el archivo.

    /**
     * Reads a document and returns its contents as a map.
     *
     * @return a map containing the document's data, or null if there are no more documents to read.
     */
    Map<String, Object> read();

    @Override
    void close();

// the Close() function is called.
type closeNotifier struct {
	rc   io.ReadCloser
	done chan struct{}
}

func (c *closeNotifier) Read(p []byte) (n int, err error) {
	n, err = c.rc.Read(p)
	if err != nil {
		if c.done != nil {
			xioutil.SafeClose(c.done)
			c.done = nil
		}
	}
	return n, err
}

func (c *closeNotifier) Close() error {

    /** Permission to read file attributes */
    public static final int FILE_READ_ATTRIBUTES = 0x00000080; // 8
    /** Permission to write file attributes */
    public static final int FILE_WRITE_ATTRIBUTES = 0x00000100; // 9
    /** Standard delete permission */
    public static final int DELETE = 0x00010000; // 16
    /** Permission to read the security descriptor */

	as := bytes.Repeat(alphabets, multiply)
	b := as[skipOffset : skipOffset+int64(len(alphabets)*(multiply-1))]
	return &DummyDataGen{
		length: totalLength,
		b:      b,
	}
}

func (d *DummyDataGen) Read(b []byte) (n int, err error) {
	k := len(b)
	numLetters := int64(len(d.b))
	for k > 0 && d.idx < d.length {
		w := copy(b[len(b)-k:], d.b[d.idx%numLetters:])
		k -= w
		d.idx += int64(w)
		n += w
	}

     * ServerMessageBlock would have to perform the same read
     * operation on the input stream, we might as will pull that
     * common functionality into the superclass and read wordCount
     * and byteCount worth of data.
     *
     * We will still use the readXxxWireFormat return values to
     * indicate how many bytes(note: readParameterWordsWireFormat
     * returns bytes read and not the number of words(but the

        byte[] smallOutputBuffer = new byte[5];
        TransCallNamedPipeResponse smallResponse = new TransCallNamedPipeResponse(mockConfig, smallOutputBuffer);

        byte[] buffer = new byte[100];

        // Try to read more data than output buffer can hold
        SMBProtocolDecodingException exception =
                assertThrows(SMBProtocolDecodingException.class, () -> smallResponse.readDataWireFormat(buffer, 0, 10));

        /*
         * Note the Transport thread isn't running yet so we can
         * read from the socket here.
         */
        try {
            this.socket.setSoTimeout(this.transportContext.getConfig().getConnTimeout());
            if (peekKey() == null) { /* try to read header */
                throw new IOException("transport closed in negotiate");
            }
        } finally {

///

## Advanced User Guide { #advanced-user-guide }

There is also an **Advanced User Guide** that you can read later after this **Tutorial - User guide**.

The **Advanced User Guide** builds on this one, uses the same concepts, and teaches you some extra features.

But you should first read the **Tutorial - User Guide** (what you are reading right now).

        bufferIndex += 2;

        // Read flags
        this.flags = SMBUtil.readInt4(buffer, bufferIndex);
        bufferIndex += 4;

        // Validate remaining buffer size for algorithms
        if (len < 8 + (compressionCount * 2)) {
            throw new SMBProtocolDecodingException("Buffer too small for compression algorithms");
        }

        // Read compression algorithms