Run as a Linux Service

In many cases, it may be useful to run your code as a system service (aka “daemon”), so you can start/stop it using a Cron job, monitor it using Monit, etc. The following is a quick guide on how to turn any Python script into a system service on Linux and Unix machines.

The first step is to create your Python script (for this example we’ll use

Create a systemd Service File

The next step is to create a systemd service file to daemonize

From the command line, type:

$ sudo nano /lib/systemd/system/qtpylib-blotter.service

…and add in the following:

Description=QTPyLib Blotter

ExecStart=/PATH/TO/PYTHON /PATH/TO/ >/dev/null 2>&1


In order to store the Blotter’s output in a log file, change the ExecStart line to:

ExecStart=/path/to/python /path/to/ > /path/to/blotter.log 2>&1


In most cases the Python executable is found under /usr/bin/python, but it can be located elsewhere (for example: /home/user/anaconda3/bin/python). You can run which python to get the path to the System’s default Python executable.

Next, change the permission on that file to 644:

$ sudo chmod 644 /lib/systemd/system/qtpylib-blotter.service

Enable The Service using systemctl

Now the system file has been defined, we need to reload systemctl:

$ sudo systemctl daemon-reload
$ sudo systemctl enable qtpylib-blotter.service

Start/Stop Your Service

Start the service

$ sudo service qtpylib-blotter start

Stop the service

$ sudo service qtpylib-blotter stop

Check the service’s status

$ sudo service qtpylib-blotter status

You shoud see something like this:

sudo service qtpylib-blotter status
● qtpylib-blotter.service - QTPyLib Blotter
   Loaded: loaded (/lib/systemd/system/qtpylib-blotter.service; enabled; vendor preset: enabled)
   Active: active (running) since Tue 2016-08-22 07:09:06 UTC; 12s ago
 Main PID: 26737 (python)
   CGroup: /system.slice/qtpylib-blotter.service
           └─26737 /usr/bin/python /home/user/