So you've written a killer python script and you want to run it in the background as a service because when you close the terminal window/SSH session it kills it. I originally worked it out when I wrote my Twitterbot app, and was going to write it up seperately then but it took me so long to get it running in the background and I tried so may things that I couldn't actually tell you how I eventually managed it!
It was only as I was working on my new project - an OLED clock for my new mediacentre pi that I finally worked out how easy it actually was; here are the instructions.
First we'll get the code using a terminal window or SSH:
cd ~ git clone https://github.com/metachris/python-posix-daemon.git cd python-posix-daemon/scr ls
so you'll see the three files which do the business:
daemon2x.py daemon3x.py daemon-example.py
you'll obviously need python at this point tp do anything so I'll assume you have this, we can try the provided example file to see if everything is working:
python daemon-example.py start
python daemon-example.py stop
to stop it.
At this point you'll notice that nothing really happened - thats because the sample dosen't actually do anything, we can have a look by openeing the file
it just sleeps for 1 second and then repeats.
If you want to see an example of a script that does something you can use my example:
It creates a log file ant writes the time to it every two seconds. Download the script:
and start it:
sudo python daemon-exampl2.py start
leave it for and few seconds then stop it:
sudo python daemon-example2.py stop
we can see the results using:
and there you have it, everything is easy when you know how. If you want to put it in you library then you just need to put it in a python sys path.
if you want to run the script at boot you'll need to
sudo nano /etc/rc.local
then type in
echo "Starting python logging daemon" sudo python /home/pi/python-posix-daemon/scr/daemon-example2.py start
but I wouldn't recommend it for this script.