Re: [ANNOUNCE] udev 0.1 release

Greg KH
2003-04-11T22:42:53Z

On Fri, Apr 11, 2003 at 03:27:19PM -0700, Perez-Gonzalez, Inaky wrote:
>
>
> > From: Greg KH [mailto:greg@kroah.com]
> >
> > But I can do a lot to prevent losses. A lot of people around here point
> > to the old way PTX used to regenerate the device naming database on the
> > fly. We could do that by periodically scanning sysfs to make sure we
> > are keeping /dev in sync with what the system has physically present.
> > That's one way, I'm sure there are others.
>
> This might be a tad over-simplification, but sysfs knows by heart when
> anything is modified, because it goes through it's interface. If we
> only care about, for example, devices, we could hook up into
> device_create() [was this the name?]; line up in a queue all the
> devices for which an plug/unplug event hasn't been delivered to user
> space and create symlinks in /sysfs/hotplug-events/.
>
> Each entry in there is a symlink to the new device directory, named with an
> increasing integer for easy serialization. When the event is fully
> processed, remove the entry from user space.

Um, how do you show a symlink to a device that is no long there when the
device is removed? :)

It would also require that users can delete files from sysfs, which
isn't currently possible. Special casing one directory for this would
be a pain.

In the end, it's a nice idea, but the current one is much simpler, and
works today :)

thanks,

greg k-h