*/
    @Override
    public int available() throws IOException {
        try (SmbFileHandleImpl fd = this.handle.ensureOpen(); SmbTreeHandleImpl th = fd.getTree()) {
            if (th.isSMB2()) {
                final Smb2IoctlRequest req = new Smb2IoctlRequest(th.getConfig(), Smb2IoctlRequest.FSCTL_PIPE_PEEK, fd.getFileId());
                req.setMaxOutputResponse(16);

            throw new IOException("Bad file descriptor");
        }
        // ensure file is open
        try (SmbFileHandleImpl fd = ensureOpen(); SmbTreeHandleImpl th = fd.getTree()) {

            if (log.isTraceEnabled()) {
                log.trace("read: fid=" + fd + ",off=" + off + ",len=" + len);
            }

            final int type = this.file.getType();
            int r, n;

    /**
     * Tests whether this file descriptor is open and valid.
     *
     * @return whether the FD is open and valid
     */
    boolean isOpen();

    /**
     * Tests whether this file descriptor was previously open but has become invalid.
     *
     * @return whether the FD was previously open but became invalid
     */
    boolean isStale();

    /**

// Package lock - implements filesystem locking wrappers around an
// open file descriptor.
package lock

import (
	"errors"
	"os"
	"sync"
)

// ErrAlreadyLocked is returned if the underlying fd is already locked.
var ErrAlreadyLocked = errors.New("file already locked")

// RLockedFile represents a read locked file, implements a special
// closer which only closes the associated *os.File when the ref count.

package disk

import (
	"os"
	"syscall"
)

// Fdatasync is fsync on freebsd/darwin
func Fdatasync(f *os.File) error {
	return syscall.Fsync(int(f.Fd()))
}

// FadviseDontNeed is a no-op
func FadviseDontNeed(f *os.File) error {
	return nil

	}
	in.expectNewline("#include")
	// Push tokenizer for file onto stack.
	fd, err := os.Open(name)
	if err != nil {
		for _, dir := range in.includes {
			fd, err = os.Open(filepath.Join(dir, name))
			if err == nil {
				break
			}
		}
		if err != nil {
			in.Error("#include:", err)
		}
	}
	in.Push(NewTokenizer(name, fd, fd))
}

// #line processing.
func (in *Input) line() {

			Op:   "open",
			Path: path,
			Err:  syscall.EINVAL,
		}
	}

	f, err := os.OpenFile(path, flag|syscall.O_SYNC, perm)
	if err != nil {
		return nil, err
	}

	if err = syscall.Flock(int(f.Fd()), lockType); err != nil {
		f.Close()
		if err == syscall.EWOULDBLOCK {
			err = ErrAlreadyLocked
		}
		return nil, err
	}

	st, err := os.Stat(path)
	if err != nil {
		f.Close()
		return nil, err

			fdMu.Lock()
			defer fdMu.Unlock()
			if len(fds) == 0 {
				return nil
			}
			fdsCopy := fds
			for _, fd := range fdsCopy {
				// Grab a fallback disk
				fds = fds[1:]
				if fd != nil && fd.IsOnline() {
					return fd
				}
			}
		}
		// Either no more disks for fallback or
		// not a storage error.
		return nil
	}

		Start:  0,
		Len:    0,
		Pid:    0,
		Type:   lockType,
		Whence: 0,
	}

	f, err := os.OpenFile(path, flag, perm)
	if err != nil {
		return nil, err
	}

	if err = syscall.FcntlFlock(f.Fd(), rlockType, &lock); err != nil {
		f.Close()
		if err == syscall.EAGAIN {
			err = ErrAlreadyLocked
		}
		return nil, err
	}

	st, err := os.Stat(path)
	if err != nil {
		f.Close()
		return nil, err

				if err != nil {
					return written, err
				}
				nw = int64(n)
			}

			// Disable O_DIRECT on fd's on unaligned buffer
			// perform an amortized Fdatasync(fd) on the fd at
			// the end, this is performed by the caller before
			// closing 'w'.
			if err = disk.DisableDirectIO(file); err != nil {
				return written, err
			}