Re: [RFC PATCH 1/1] fanotify.7, fanotify_init.2, fanotify_mark.2: Document FAN_REPORT_FID and directory modification events

[Jan Kara <jack@suse.cz>]

On Sat 16-03-19 23:35:21, Matthew Bobrowski wrote:
> On Wed, Mar 13, 2019 at 04:07:55PM +0100, Jan Kara wrote:
> > Thanks for the manpage updates! Some small comments below.
> > 
> > On Tue 12-03-19 13:48:29, Matthew Bobrowski wrote:
> > > +.TP
> > > +.B FAN_MOVED_FROM
> > > +Create an event when a marked file or directory is moved from the current
> > > +location.
> > > +.TP
> > > +.B FAN_MOVED_TO
> > > +Create an event when a marked file or directory is moved to a new
> > > +location.
> > 
> > For these two events (like other directory events), marked thing is
> > actually again the parent directory - i.e., these events trigger is
> > something is moved to / from marked directory. So I think it would be
> > clearer and use the same language like e.g. for FAN_CREATE and speak about
> > marked parent directory.
> 
> Sure, what changing this to: 
> 
> --
> .B FAN_MOVED_FROM
> Create an event when a file or directory has been moved from a marked parent
> directory.
> .TP
> .B FAN_MOVED_TO
> Create an event when a file or directory has been moved to a marked parent
> directory.
> --
> 
> Do you think that's better? I think it's cleaner, but also at the same time
> more precise.

Yes, I think that's better.

> > > +.B FAN_ATTRIB
> > > +A file or directory metadata was changed.
> > > +.TP
> > > +.B FAN_CREATE
> > > +A child file or directory was created in a watched parent.
> > > +.TP
> > > +.B FAN_DELETE
> > > +A child file or directory was deleted in a watched parent.
> > > +.TP
> > > +.B FAN_DELETE_SELF
> > > +A watched file or directory was deleted.
> > > +.TP
> > > +.B FAN_MOVED_FROM
> > > +A watched file or directory was moved from the current location.
> > > +.TP
> > > +.B FAN_MOVED_TO
> > > +A watched file or directory was moved to a new location.
> > 
> > The same comment here about parent directory being actually marked.
> 
> Sure, intending to change this to:
> 
> --
> .B FAN_MOVED_FROM
> A file or directory has been moved from a watched parent directory.
> .TP
> .B FAN_MOVED_TO
> A file or directory has been moved to a watched parent directory.
> --
> 
> Thoughts?

Looks good to me!

> > > +For example, when an fanotify file descriptor is created using
> > > +.B FAN_REPORT_FID
> > > +the
> > > +.I info_type
> > > +field of this header is set to
> > > +.BR FAN_EVENT_INFO_TYPE_FID .
> > > +Event listeners can use this field to check that events of the correct
> > > +type are being received.
> > 
> > I think here you should also speak about the 'len' field in the header
> > which can be used to skip additional information that is not understood /
> > uninteresting for the receiver of the event.
> 
> I don't have any objections to add this as I do believe mentioning it has
> added benefit. Perhaps we could consider adding in a section which describes
> all the fanotify_event_info_header fields? Maybe it's not necessary though,
> and just mentioning these two fields here would be enough. Thoughts?

Well, there are just two fields - 'info_type' and 'len'. There's also 'pad'
but that doesn't really count ;). So I think that briefly explaining 'len'
is all that's needed. If you want to formalize this a bit more in a
separate section, I'm not opposed but I don't think it's really necessary.

Thanks!

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR