thinking of updating the canonical online udev document

[greg@kroah.com (Greg KH)]

On Tue, Apr 26, 2011 at 09:06:02AM -0400, Robert P. J. Day wrote:
> On Tue, 26 Apr 2011, Greg KH wrote:
> 
> > On Tue, Apr 26, 2011 at 08:12:44AM -0400, Robert P. J. Day wrote:
> > >
> > >   [not sure if this is the right forum for this, but i suspect others
> > > on this list might be interested so ... there you go.]
> >
> > The linux-hotplug at vger.kernel.org list is where this should be
> > discussed, please take it there.
> >
> > >   as part of a device driver course i may very well be teaching in the
> > > near future (still waiting to hear), i'm thinking of adding a sizable
> > > section on how udev works (after i figure all that out, of course.)
> > >
> > >   currently, the canonical udev document is this one:
> > >
> > >   http://reactivated.net/writing_udev_rules.html
> >
> > That doc could almost be removed entirely now, as no one should need
> > to mess with udev rules "by hand" anymore thanks to devtmpfs and the
> > default udev rules that are in all distros (with one notable
> > exception.)
> >
> > What is your goal in redoing this?  Why would a user/developer ever
> > need to mess with udev on their own anymore?
> >
> > Ideally, it should all "just work" now, and I think it does given
> > your previous emails about the confusion as to how your driver was
> > automagically creating the correct device nodes without any help
> > from you :)
> 
>   so you don't see much need for that level of detail for udev
> anymore?  at the very least, i can see the need for what i asked about
> before -- how a misc device suddenly showed up under /dev, and with
> what properties.

You want a "how does this all work" type document, which is aimed for a
developer, not a user, right?  That's different from the above mentioned
document in quite a number of ways.

>   is there a doc explaining that somewhere?  because i definitely went
> looking before i asked that question here.

I wrote something like that a long time ago for LDD3 and later updated
it for lwn.net I think, if you want to start with that.

good luck,

greg k-h