From mboxrd@z Thu Jan  1 00:00:00 1970
From: ebiederm@xmission.com (Eric W. Biederman)
Subject: Re: [PATCH v4] signal: add taskfd_send_signal() syscall
Date: Thu, 06 Dec 2018 08:46:57 -0600
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To: Florian Weimer <fweimer@redhat.com>
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Florian Weimer <fweimer@redhat.com> writes:

> * Eric W. Biederman:
>
>> Floriam are you seeing a problem with this behavior or the way Christian
>> was describing it?
>
> My hope is that you could use taskfd_send_signal one day to send a
> signal to a process which you *known* (based on how you've written your
> application) should be running and not in a zombie state, and get back
> an error if it has exited.
>
> If you get this error, only then you wait on the process, using the file
> descriptor you have, and run some recovery code.
>
> Wouldn't that be a reasonable approach once we've got task descriptors?

Getting an error back if the target was a zombie does seem reasonable,
as in principle it is an easy thing to notice, and post zombie once the
process has been reaped we definitely get an error back.

I also agree that it sounds like an extension, as changing the default
would violate the princile of least surprise.

Eric