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From: Flavio Castelli <micron@bglug.it>
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Date: Fri, 8 Jun 2007 10:58:01 +0200
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Subject: Re: file system notifications
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On Sunday 03 June 2007 00:46, you wrote:
> I am curious. Have you tried fam? As far as I know, fam was created so
> that developers won't have to bother about the mechanism they should use
> to get file notifications.
Yes I looked at fam and gamin (a project that extends fam) but I didn't cho=
ose=20
them.

=46am has lot of problems (first of all in some situations it can take lots=
 of=20
cpu cicles) and its development seems abandoned.
Both fam and gamin use native file system notification structures when=20
available and use polling as a fall-back mechanism. Since kqueue has some=20
limitations (as exposed in my first post), it's really hard to develop a go=
od=20
notification mechanism without falling back to polling or using a=20
mixed-approach.

Just an example.
Suppose you have told kqueue to watch dir /tmp/foo. If you=20
create/delete/rename/update a file/dir inside /tmp/foo, kqueue will tell yo=
u=20
an event has occurred inside the watched directory. Kqueue's limitation is=
=20
the lack of informations associated to the event since it _doesn't_ tell wh=
at=20
happened. So a program has to walk across the watched dir (where the event=
=20
took place) and find the changes that happened.

Now, what I really like to know is if there is another system notification=
=20
mechanism that works like inotify or fsevents.
I would also use kqueue if there's a way to make it generate more=20
informations.

Cheers
	Flavio
=2D-=20
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