what is the precise udev event that handles miscdevices?

Greg KH greg at kroah.com
Wed Apr 1 08:45:40 EDT 2015

On Wed, Apr 01, 2015 at 08:18:13AM -0400, Robert P. J. Day wrote:
> On Wed, 1 Apr 2015, Greg KH wrote:
> > In fact, no one does this anymore, and people run systems without
> > udev and have dynamic device nodes just fine.  And have been doing
> > so for years, udev isn't needed for device nodes anymore, if that's
> > all you care about.
>   yup, i can see that now. although i would *think* that you could
> still use udev to go above and beyond just creating device files, to
> do things like create symlinks, run arbitrary programs and so on. but,
> yes, for just straight device file manipulation, devtmpfs is
> sufficient.

Yes, your persistent device names (the whole reason udev was created in
the first name) are still created by udev, as that is best left up to
userspace.  Those are symlinks to the device nodes devtmpfs created.

Also, sometimes you want different group/user permissions on device
nodes from what the kernel provides (the kernel doesn't know the group
file), so udev will modify the mode and owners of some nodes as well.

good luck!

greg k-h

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