Buildroot-ts Startup Scripts

Buildroot defaults to using the BusyBox init system, and all of our provided configurations use this as well. The following custom startup script uses this format. For information on other init systems that Buildroot can use, as well as creating startup scripts for these, see the Buildroot manual.

The most straightforward way to add an application to startup is to create a startup script. This example startup script that will toggle the red LED on during startup, and off during shutdown. In this case the script is named customstartup which can be changed as needed.

Create the file /etc/init.d/S99customstartup with the following contents. Be sure to set the script as executable!

#! /bin/sh
# /etc/init.d/customstartup

case "$1" in
  start)
    echo 1 > /sys/class/leds/red-led/brightness
    ## If you are launching a daemon or other long running processes
    ## this should be started with
    # nohup /usr/local/bin/yourdaemon &
    ;;
  stop)
    # if you have anything that needs to run on shutdown
    echo 0 > /sys/class/leds/red-led/brightness
    ;;
  *)
    echo "Usage: customstartup start|stop" >&2
    exit 3
    ;;
esac
  
exit 0

Note:

The $PATH variable is not set up by default in init scripts so this will either need to be done manually or the full path to your application must be included.

Buildroot provides numerous mechanisms to create this file in the target filesystem at build time. See the Buildroot manual for more information on this.

This script will be automatically called at startup and shutdown thanks to the file location and naming. However, it can also be manually started or stopped:

/etc/init.d/S99customstartup start
/etc/init.d/S99customstartup stop