Kill(entireProcessTree: true) - cannot terminate self (?)

[notofug]

This works as expected and terminates application :
Process.GetCurrentProcess().Kill(entireProcessTree: false);

This throws InvalidOperation
Process.GetCurrentProcess().Kill(entireProcessTree: true);

Exception origin here ;

runtime/src/libraries/System.Diagnostics.Process/src/System/Diagnostics/Process.NonUap.cs

Line 25 in 10438a5

if (IsSelfOrDescendantOf(GetCurrentProcess()))

**

Would it be possible to allow also the 'self-termination-with-children' scenario gracefully ?

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Issue Details

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This works as expected and terminates application :
Process.GetCurrentProcess().Kill(entireProcessTree: false);

This throws InvalidOperation
Process.GetCurrentProcess().Kill(entireProcessTree: true);

Exception origin here ;

runtime/src/libraries/System.Diagnostics.Process/src/System/Diagnostics/Process.NonUap.cs

Line 25 in 10438a5

if (IsSelfOrDescendantOf(GetCurrentProcess()))

**

Would it be possible to allow also the 'self-termination-with-children' scenario gracefully ?

Author:	notofug
Assignees:	-
Labels:	area-System.Diagnostics.Process, untriaged
Milestone:	-

[alexrp]

The trouble here is that entireProcessTree: true starts by killing the target process so that no further children can be created. That's obviously not going to work if the target is the current process.

That said, there's probably an argument to be made that the developer likely has enough control over the current process to be reasonably certain that it won't spawn any child processes, in which case the current process could be special-cased to kill the children first?

[notofug]

OK thanks, that explains the observation ; a racing-prevention kill-ordering.
Perhaps another way would be to disallow process-creation (with a flag?) when initiating Kill( ) and reverse the order?
The developer could also explicitly Kill all children in advance but I see no obvious API for enumerating them?

[skyoxZ]

I wrote a solution letting Windows auto kills my children processes when my application exits some years ago but I can't find the code now. It's something using JobObject.

[adamsitnik]

The best we can do right now is to mark it as help wanted (old up-for-grabs). The person who would like to pick up this task needs to study the current implementation, do a research whether it's possible to implement it on Unix and Windows and depending on the outcome, send a PR with a fix or share explanation why it's impossible and update the docs.

[MojtabaTajik]

@adamsitnik Can I pick this ticket up?

[adamsitnik]

@adamsitnik Can I pick this ticket up?

@MojtabaTajik yes! Please let me know if you have any questions

[MojtabaTajik]

@adamsitnik
In Windows, we can use "Process32First" and "Process32Next" to iterate through all process information, retrieve their parent ID, and compare it against the current process ID. If the IDs are equal, the process is a child of the current process, and we can terminate them before killing ourselves.

I just tested this workaround, and it works fine.

Should I go for it and open a PR?

For Linux, I'm still investigating.

[hjrb]

in .NET Core Process.Kill(true) does not work correctly. It will only kill the root process. Children will not be killed!