deltaolz.blogg.se - Python subprocess background nohup

I will mock this scenario and will show how to run the Python script inside a virtual environment in the background that writes partial output to a file. We also want to run the script in the background without blocking a terminal window. print statement debugging) from the script during the execution process. We may need to check the intermediate results (e.g. Let's assume, the script requires a long time to finish. To keep the global environment clean, we use a virtual environment ( venv) to install the dependencies. Suppose, we have a Python script that uses some Python packages. Please also see this article and this article.Jpython high-performance computing python Scenario The file nohup.out contained: Terminal close - query abortedįor some explanation on nohup and background processes please see this post. Without disown, the MySQL import could be aborted if you closed the Putty window (despite we used nohup).Īt least it was aborted for me.

disown will disable sending the SIGHUP signal to all active jobs.

& at the end of the line sends the command to the background.

And sends all the stdout and stderr output to the file nohup.out (by default).

nohup – prevents the process from receiving SIGHUP (Signal Hang UP) signal ( source).

You can кun the script mysql_import.sh in the background (instead of detaching a session) and close the Putty window: cd /var/www Other Solutions 2.1 Run the Process in the Background Please see this post for screen keyboard shortcuts.Ģ. To destroy a session, reattach the session, then press Ctrl A, then K, and then Y.

Then you can reattach any session as: screen -r įor example, if the session ID is 1672, then you can reattach it as: screen -r 1672 Type "screen -r tty.host" to resume one of them.Īlso, if you have several detached sessions, you can list them (and their IDs) with: screen -ls There are screens on:ġ2204 ( 02:01:10 AM) (Detached)ġ2204 ( 02:00:17 AM) (Detached)ġ2204 ( 01:22:31 AM) (Detached) If there are several detached sessions, the output would be like this: There are several suitable screens on:ġ2204 ( 02:01:11 AM) (Detached)ġ2204 ( 02:00:18 AM) (Detached)ġ2204 ( 01:22:32 AM) (Detached)

To reattach the detached session: screen -r Check that the process is still running: ps -aux | grep mysql_import Press Ctrl A and then D to detach the session.Īlso, please see this post on detaching sessions.Ħ.