Enable autostart
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Autostart
Start app to display IP on Regbot display, log CPU temperature and synchronize hostname
Make an on-reboot script in the home directory
cp ~/svn/robobot/setup/on_reboot.bash ~/
This file is something like:
#!/bin/bash # script to start applications after a reboot # # run the app to show IP of raspberry on the Teensy display. mkdir -p /home/local/svn/log cd /home/local/svn/log # save the last reboot date echo "Rebooted" >> /home/local/rebootinfo.txt date >> /home/local/rebootinfo.txt # start IP display (and button start) task ../robobot/ip_disp/build/ip_disp & # save PID for IP display task for debugging echo "ip_disp started with PID:" >> /home/local/rebootinfo.txt pgrep -l ip_disp >> /home/local/rebootinfo.txt exit 0
Use crontab to run this script at reboot
crontab -e
If asked, select the preferred editor (suggesting nano).
Add this line at the end:
@reboot /home/local/on_reboot.bash
Hostname update
A script updates the Raspberry Pi hostname, with the name in ~/svn/log/robotname. The script rename_host.bash is:
#!/bin/bash hn=`hostname` f="/home/local/svn/log/robotname" if [ -f $f ]; then # file exist # get (new) name in file to variable nn nn=`cat $f` echo "found name " $nn yy=$(expr length $nn) if [ $yy -gt 2 ]; then # length is longer than 2 characters if [ $hn != $nn ]; then # replace old hostname with new echo ++++++++++ >> rebootinfo.txt date >> rebootinfo.txt echo new name is $nn, so rename host from $hn >> rebootinfo.txt hostnamectl set-hostname $nn sed -i "s/$hn/$nn/g" /etc/hosts fi fi else echo "File >" $f "< not found." fi
The script needs to be run as root; it is, therefore set to run as part of the boot process.
Create the script in /etc/init.d
sudo nano /etc/init.d/host_rename.sh
Enter the following lines into the new file.
#!/bin/bash bash /home/local/svn/robobot/setup/rename_host.bash
Make the file executable and add it to run-level 2 (before networking is started)
sudo chmod +x /etc/init.d/host_rename.sh sudo ln -s /etc/init.d/host_rename.sh /etc/rc2.d/S99host_rename
The script is then executed when the Raspberry boots, and if the hostname does not match that of the Teensy, then the hostname is modified.
The script makes a note in the file '/home/local/svn/robobot/setup/rebootinfo.txt (owned by 'root') if the name is changed.