Automatically launch your application

You've just developed a state of the art application and want it to be launched each time you boot your APF ? Then this small tutorial is for you !

System startup

First, a small remainder: when you start your board, here is how all things are started:

1. U-Boot initializes the system and load Linux
2. Linux mounts its rootfs and launches /sbin/init
3. init process checks its /etc/inittab config file and executes the instructions it contains
4. this config files generally asks init to launch /etc/init.d/rcS
5. /etc/init.d/rcS gets all scripts in /etc/init.d/ directory which start with a S, and executes them in ascending order

Adding your own application in the start process

• creates a shell script in /etc/init.d/:

 # touch /etc/init.d/S99app
 # chmod a+x /etc/init.d/S99app

• edit it

 # vi /etc/init.d/S99app

• put in it the following content (replace /usr/bin/your_app with your application name & path):

#!/bin/sh

# Loading the modules needed by my app:
modprobe xxxxx
 
# Launching my app:
/usr/bin/your_app &          # <-- Don't forget the "&" otherwise other system stuff won't start until you leave your app !!!

exit 0

• save your changes and !! Test it !!

# /etc/init.d/S99app

• That's it ! You can now reboot:

# sync
# reboot

Links

• How to customize your boot Logo