this.access = access | SmbConstants.FILE_WRITE_DATA;

        try (SmbTreeHandleImpl th = file.ensureTreeConnected()) {
            this.smb2 = th.isSMB2();
            try (SmbFileHandleImpl fh = ensureOpen()) {
                if (append) {
                    this.fp = fh.getInitialSize();
                }
                init(th);
                if (!append && this.smb2) {

     */
    public void open() throws CIFSException {
        try (SmbFileHandleImpl fh = ensureOpen()) {}
    }

    /**
     * @param file
     * @param openFlags
     * @return
     * @throws SmbException
     */
    synchronized SmbFileHandleImpl ensureOpen() throws CIFSException {
        if (this.handle == null || !this.handle.isValid()) {

        when(mockFileHandle.isValid()).thenReturn(false, true); // First false to trigger ensureOpen, then true
        when(mockFileHandle.getFileId()).thenReturn(new byte[16]);
        when(mockFileHandle.acquire()).thenReturn(mockFileHandle);

        // Mock for ensureOpen to reopen file
        when(mockFile.openUnshared(anyInt(), anyInt(), anyInt(), anyInt(), anyInt())).thenReturn(mockFileHandle);

    /**
     * Ensures that the file handle is open and returns it.
     *
     * @return file handle
     * @throws CIFSException if an error occurs opening the file
     */
    SmbFileHandle ensureOpen() throws CIFSException;

    /**
     * Receive data from the pipe
     *
     * @param buf buffer to receive data into
     * @param off offset in the buffer
     * @param length maximum length to receive

        }
    }

    int getNextNameTrnId() {
        if ((++this.nextNameTrnId & 0xFFFF) == 0) {
            this.nextNameTrnId = 1;
        }
        return this.nextNameTrnId;
    }

    void ensureOpen(final int timeout) throws IOException {
        this.closeTimeout = 0;
        if (this.transportContext.getConfig().getNetbiosSoTimeout() != 0) {

     *
     * @return true if the stream is open, false otherwise
     */
    public boolean isOpen() {
        return file.isOpen();
    }

    void ensureOpen() throws IOException {
        // ensure file is open
        if (!file.isOpen()) {
            file.open(openFlags, access | SmbConstants.FILE_WRITE_DATA, SmbFile.ATTR_NORMAL, 0);
            if (append) {

        }
    }

    int getNextNameTrnId() {
        if ((++nextNameTrnId & 0xFFFF) == 0) {
            nextNameTrnId = 1;
        }
        return nextNameTrnId;
    }

    void ensureOpen(final int timeout) throws IOException {
        closeTimeout = 0;
        if (SO_TIMEOUT != 0) {
            closeTimeout = Math.max(SO_TIMEOUT, timeout);
        }

        @DisplayName("open() acquires handle and closes it")
        void openDelegatesEnsureOpenAndCloses() throws Exception {
            SmbFileInputStream in = newStream();
            in.open();
            // ensureOpen returns acquired handle; try-with-resources must close it
            verify(mockHandle, times(1)).close();
            verify(mockHandle, atLeastOnce()).acquire();
        }

        @Test