[yocto] Run application at system boot

[Laurentiu-Cristian Duca]

Hello yocto community,

  I want to know a few things
about how to configure yocto such that
- a simple application (let's say a hello world C program
from a new recipe) is run at boot time.
- run a kernel module from a simple recipe at boot time
and automatically build its "/dev/hello" interface file
(which normally is done by hand using mknod).

  I appreciate any hint, example or tutorial regarding this questions.

Thank you very much,
Laurentiu