If you decide to go with a cron job (and PID file handling) then consider reading this PEP 3143 and perhaps using its reference implementation.Īs I alluded to in my other comments, robust PID file handling is tricky. or systemd or others.īut you can look at alternatives init and in the Python code for Pardus: mudur daemon in particular. Other options are to use features in Ubuntu upstart. Another method is to use the supervisor daemon from DJ Bernstein's daemontools package.

if you're using the old SysV init system. One of the oldest is a 'respawn' entry in /etc/inittab. There are a number of ways to monitor and respawn processes under UNIX/Linux. So, if your script is not running, the pgrep will fail since it will find nothing and your script will be launched.

The || symbol means 'do this if the previous command failed'. pgrep -f makes it search the entire command line used to launch the program and not only the program name (useful because this is a python script). pgrep foo will search for a program named foo and return its process identifier. The actual command being run is pgrep which searches running processes for the string given in the command line. The official Ubuntu docs on cron are here. See here for a nice little tutorial on cron. You just created a new crontab which will be run every 5 minutes and launch your script unless it is already running. This will bring up a window of your favorite text editor.Īdd this line to the file that just opened */5 * * * * pgrep -f testing.py || nohup python /home/you/scripts/testing.py > test.out

Have your cron look for your script and relaunch it if it dies.Ĭreate a new crontab by running crontab -e. You could also take a more shell oriented approach. This is my python script - #!/usr/bin/python Testing start/running, process ps ax | grep testing.pyĢ7806 pts/3 S+ 0:00 grep -color=auto testing.pyĪny idea why px ax is not showing me anything? And how do I check whether my program is running or not? I ran below sudo command to start it but I cannot see that process running behind using ps ax? sudo start testing Is this possible to do? If yes, then what's the best way to solve these kind of problem?Īfter creating the nf file like this - chdir /tekooz So I am thinking to have some sort of cron agent in bash shell script which can restart my above Python script automatically if it is killed for whatever reason. Now, it might be possible that at some stage my above Python script can die for whatever reason. I am running my Python script in the background in my Ubuntu machine (12.04) like this - nohup python testing.py > test.out &

Python subprocess background nohup