Re: devfs vs udev, thoughts from a devfs user

Chris Friesen
2004-02-10T18:13:23Z

Mike Bell wrote:

> No, you misunderstand. I'm not suggesting that sysfs /should/ export
> device files. I'm saying that sysfs exporting type/major/minor as files
> is not really that different from exporting full-fledged device files.
> Making udev a sort of ugly-hack devfsd.

What names would you use for your device files? This is the key
difference. With udev it gets a notification that says "I have a new
block device", it then looks it up, applies the rules, and creates a new
entry. The whole point is to move the naming scheme into userspace for
easier management.

You could have the kernel export a simple devfs with a hardcoded naming
scheme based on similar ideas as what is in sysfs (which would then make
sysfs and the daemon optional for tiny embedded setups), but the only
advantage over just exporting the information in sysfs is to save a few
bytes at the cost of yet another filesystem to maintain.

Chris

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