Hi all, I have the following code: ```ProcessBuilder("/bin/sh", "-c", "java -jar $jarName -f $...

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[New111]

Hi all, I have the following code:

ProcessBuilder("/bin/sh", "-c",
      "java -jar $jarName -f $configName ${args.joinToString(" ")} &")
      .start()

how can I redirect stdout of the child to stdout of the parent process (so I could see all the messages together) ? The following code using inheritIO doesn't work either:

ProcessBuilder("/bin/sh", "-c",
        "java -jar $jarName -f $configName ${args.joinToString(" ")} &")
        .inheritIO()
        .start()

Any clue where the problem is ? Is it somehow related to the fact that the child process writes to log file ?

[spand]

What is that & doing at the end ?

[Alowaniak]

It starts it as a child/background process

[New111]

To put it in the background using unix features (I know this is horrible ...)

[Alowaniak]

Don't you have to use unix features to redirect the child's stdout?

[New111]

Can I somehow redirect the child's stdout using kotlin ? I don't like this code to be honest ...

[New111]

I mean: start some process as a child and put it background and redirect its stdout to parents stdout all using kotlin features.

[spand]

I am not sure why you need the sh part. Isnt starting it with process builder the same as a background process?

[spand]

This seems to suggest that a child process can/will outlive its parent: https://stackoverflow.com/questions/269494/how-can-i-cause-a-child-process-to-exit-when-the-parent-does

[New111]

Hmm, that is true actually ... but we don't want to do that ...

[spand]

Then why do you want to send it to the background ?

[New111]

to carry on with other tasks

[spand]

But nothing prevents your kotlin app to progress with other tasks?

[New111]

run the subprocess in the background, do some other tasks but still watch the process - sometimes kill the child and restart it with some other parameters.

[Alowaniak]

I think you could do the other tasks and watching the process in kotlin/newly started processes though?

[New111]

This is all going to run in a container so my guts says that the & is an anti-pattern. How do I start another process in the background in kotlin > What is the kotlin way to do that ?

[Alowaniak]

I would think that ProcessBuilder...start() starts the process in the background...? (Or rather just starts a new process which runs on it own etc.)
So what exactly do you mean with background?

[New111]

The main process starts the child process (which does the real job) but the parent monitors the child and kills/restarts the child when needed.