Re: [PATCH v2 0/7] CLONE_FD: Task exit notification via file descriptor

From: Florian Weimer
Date: Mon Jun 15 2015 - 06:06:17 EST


On 05/29/2015 10:27 PM, Thiago Macieira wrote:

>> It has been suggested (e.g.,
>> <https://sourceware.org/bugzilla/show_bug.cgi?id=15661#c3>) that you can
>> use the existing clone(2) without specifying SIGCHLD to create a new
>> process. The resulting child process is not supposed to show up in
>> wait(2), only in a waitpid(2) (or similar) explicitly specifying the
>> PID. Is this not the case?
>
> Hi Florian
>
> That sounds orthogonal to what we're looking for. Our objective is to get
> notification of when the child exited without resorting to SIGCHLD. If we use
> the regular clone(2) without SIGCHLD and without CLONE_FD, we get no
> notification. The only way to know of the child's termination is by a blocking
> waitpid(2), like you indicated, which is counter productive to our needs.
>
> We need something we can select(2)/poll(2) on.

Thanks for the clarification. I agree that this is a separate and quite
sensible use case.

--
Florian Weimer / Red Hat Product Security
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