Kill all related process when exiting

[Kastakin]

I noticed that on Windows the processes are not exited correctly.
The execa package create an Rscript process that launches the start-shiny.R script in main folder. This in turn creates an R process and another Rscript process, both related to the Shiny dashboard.

When closing the main window the main process created by execa is terminated but the other two are left there as zombie processes and the Shiny dashboard can still be accessed if a web browser is pointed to the correct port.

I propose a workaround I implemented for an upcoming app we are developing at my university that is based on this comment I found in a related issue on the execa GitHub.

The related pid of the process are kept in memory and manually terminated when exiting if they are still alive.

[jhk0530]

Hi Kastakin.

As you mentioned. It's annoying that R doesn't exit clearly in windows.

I understand using pidtree will clear this issue.

Right?

[Kastakin]

That is correct!
The modification to the code I did use pidtree to get the actual list of R child processes and terminate them if they are alive once the application is closed.

[jhk0530]

Nice work.
I tried it and it works as expected.