ueventd handles uevent in /sys, creates nodes in /dev
uevent is based on netlink
android ueventd:
https://android.googlesource.com/platform/system/core/+/master/init/README.ueventd.md
how uevent works:
https://stackoverflow.com/questions/22803469/uevent-sent-from-kernel-to-user-space-udev
https://issuu.com/hibadweib/docs/open_source_for_you_-_october_2012/1 (page 72)