Subject: Re: device special files
To: Matthew Mondor <>
From: Petar Bogdanovic <>
List: tech-kern
Date: 11/16/2005 08:36:11
Matthew Mondor wrote:
> They are only created as a convenience in case you have such a device.
> Trying to use such an unexisting device will result in "device not
> configured" errors.  If we had a devfs, a virtual fs somewhat like /kern
> and /proc, it would be possible to have them magically appear only for
> configured devices;  However since we are currently using a
> general-purpose filesystem to store device files, the MAKEDEV script is
> generally used by default and just populates /dev with any that has may
> have potential use.
> Note that under a chroot(2) setup, /dev is often much smaller and
> typically only has /dev/null and other necessary device files strictly
> used by the application ran under the new root environment.  For uses
> such as these, even if we had a devfs the traditional method would still
> find its place.

Great - that's what I wanted to know. :)

> If you are interested in knowing more about BSD/unix internals, there
> are a number of documentation sources you could find, this mailing
> list's archive for instance often had threads on the subject, such as
> "BSD kernel books recommendation" and "Learning the kernel" threads in
> 2004 which are pointing to many good references...

Thanks, I will take a look at the archives!

Kind regards,