FUSE 3.0.0pre0 (2016-10-03)

• This is a preview release. Functionality and API may still change
  before the 3.0.0 release.

• The fuse_lowlevel_new function has been renamed to
  fuse_session_new and no longer interprets the --version or --help
  options. To print help or version information, use the new
  fuse_lowlevel_help and fuse_lowlevel_version functions.

• There are new fuse_session_unmount and fuse_session_mount
  functions that should be used in the low-level API. The fuse_mount
  and fuse_unmount functions should be used with the high-level API
  only.

• Neither fuse_mount nor fuse_session_mount take struct fuse_opts
  parameters anymore. Mount options are parsed by fuse_new (for the
  high-level API) and fuse_session_new (for the low-level API)
  instead. To print help or version information, use the new
  fuse_mount_help and fuse_mount_version functions.

• The fuse_lowlevel_notify_* functions now all take a struct fuse_session parameter instead of a struct fuse_chan.

• The channel interface (fuse_chan_* functions) has been made
  private. As a result, the typical initialization sequence of a
  low-level file system has changed from ::

    ch = fuse_mount(mountpoint, &args);
    se = fuse_lowlevel_new(&args, &lo_oper, sizeof(lo_oper), &lo);
    fuse_set_signal_handlers(se);
    fuse_session_add_chan(se, ch);
    fuse_daemonize(fg);
    if (mt)
        fuse_session_loop_mt(se);
    else
        fuse_session_loop(se);
    fuse_remove_signal_handlers(se);
    fuse_session_remove_chan(ch);
    fuse_session_destroy(se);
    fuse_unmount(mountpoint, ch);
  

  to ::

    se = fuse_session_new(&args, &ll_ops, sizeof(ll_ops), NULL);
    fuse_set_signal_handlers(se);
    fuse_session_mount(se, mountpoint);
    fuse_daemonize(fg);
    if (mt)
        fuse_session_loop_mt(se);
    else
        fuse_session_loop(se);
    fuse_remove_signal_handlers(se);
    fuse_session_unmount(se);
    fuse_lowlevel_destroy(se);
  

  The typical high-level setup has changed from ::

    ch = fuse_mount(*mountpoint, &args);
    fuse = fuse_new(ch, &args, op, op_size, user_data);
    se = fuse_get_session(fuse);
    fuse_set_signal_handlers(se);
    fuse_daemonize(fg);
    if (mt)
        fuse_loop_mt(fuse);
    else
        fuse_loop(fuse);
    fuse_remove_signal_handlers(se);
    fuse_unmount(mountpoint, ch);
    fuse_destroy(fuse);
  

  to ::

    fuse = fuse_new(&args, op, op_size, user_data);
    se = fuse_get_session(fuse);
    fuse_set_signal_handlers(se);
    fuse_mount(se, mountpoint);
    fuse_daemonize(fg);
     if (mt)
        fuse_loop_mt(fuse);
    else
        fuse_loop(fuse);
    fuse_remove_signal_handlers(se);
    fuse_unmount(se);
    fuse_destroy(fuse);
  

  File systems that use fuse_main are not affected by this change.

  For integration with custom event loops, the new fuse_session_fd
  function provides the file descriptor that's used for communication
  with the kernel.

• Added clone_fd option. This creates a separate device file
  descriptor for each processing thread, which might improve
  performance.

• The (high- and low-level) rename handlers now takes a flags
  parameter (with values corresponding to the renameat2 system call
  introduced in Linux 3.15).

• The "ulockmgr_server" has been dropped.

• There is a new (low-level) readdirplus handler, with a
  corresponding example in examples/fuse_lo-plus.c and a new
  fuse_add_direntry_plus API function.

• The (high-level) readdir handler now takes a flags argument.

• The (high-level) filler function passed to readdir now takes an
  additional flags argument.

• The (high-level) getdir handler has been dropped.

• The flag_nullpath_ok and flag_utime_omit_ok flags have been
  dropped.

• The (high-level) utime handler has been dropped.

• The fuse_invalidate function has been removed.

• The fuse_is_lib_option function has been removed.

• The fh_old member of struct fuse_file_info has been dropped.

• The type of the writepage member of struct fuse_file_info was
  changed from int to unsigned int.

• The struct fuse_file_info gained a new poll_events member.

• There is a new fuse_pkgversion function.

• The fuse_off_t and fuse_ino_t changed from unsigned long to
  uint64_t, i.e. they are now 64 bits also on 32-bit systems.

• The type of the generation member of `struct fuse_entry_param*
  changed from unsigned to uint64_t.

• The (low-level) setattr handler gained a FUSE_SET_ATTR_CTIME bit
  for its *to_set parameter.

• The struct fuse_session_ops data structure has been dropped.

• The documentation has been clarified and improved in many places.