Re: [fuse-devel] SETATTR and fuse-operations

[Anatol P. <ana...@gm...>]

Hi

On Fri, May 25, 2012 at 3:53 PM, Han-Wen Nienhuys <ha...@gm...> wrote:

> On Fri, May 25, 2012 at 4:46 PM, Christopher Howard
> <chr...@fr...> wrote:
> > 2) In creating my first FUSE-based file system, I have been following
> > one of the examples that uses the fuse-operations struct, as opposed to
> > fuse_lowlevel_ops. However, in trying to test my write function (by
> > editing a file with a text editor) I keep getting the error
> >
> > code:
> > --------
> > unique: 22, opcode: SETATTR (4), nodeid: 3, insize: 128
> >   unique: 22, error: -38 (Function not implemented), outsize: 16
> > --------
> >
> > But fuse_operations doesn't have a setattr function, only
> > fuse_lowlevel_ops. Does this mean I have to use fuse_lowlevel_ops?
>
> setattr is usually used to truncate.  Doesn't the high level interface
> have truncate function to implement?
>

Not only truncate/ftruncate but also for chmod/chown/utime

Christopher, depending on what attributes it tries to set fuse library
calls one (or several) of the high-level functions
(truncate/ftruncate/chmod/chown/utime/utimens). If at least one of the
required functions is not implemented then ENOSYS error is returned.