Re: State of devfs in 2.6?

Mark Mielke
2003-12-09T20:19:52Z

On Tue, Dec 09, 2003 at 09:21:56AM +0100, Holger Schurig wrote:
> Devfs for embedded devices is just great. It's all in the kernel, no
> external process to run (I use my embedded stuff without devfsd). I'm using
> it for about one year with various kernels.

I don't see why 'all in the kernel' is the best approach, embedded or
otherwise. I believe udev is being written to execute with a minimal
runtime environment. No glibc, or other such beasts.

> * space. devfs doesn't eat space like the MAKEDEV approach.

Can you prove this? tmpfs doesn't seem to take up much space, and given
that only devices that exist will require data structures in both cases,
it seems to me that the issue is a little irrelevant in either case.

> * simplicity: I run my system without devfsd and without an initial ramdisk.
> All needed modules are simply compiled into the kernel.

Isn't this an argument for udev?

> * No need for overcomplification, e.g a process that has to be started
> before userspace touches /dev, a specially compiled uclibc-based proggy in
> an initrd

Many of us believe that devfs is 'over-complification'.

> So, when /dev is accessed by userspace, all is there and well.

True in either case...

mark

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