From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: [PATCH] scripts: environment: Properly handle SIGINT.
Date: Sun, 27 Mar 2016 19:35:13 +0200
Message-ID: <87zitjygby.fsf@gnu.org>
References: <87pouhbd46.fsf@izanagi.i-did-not-set--mail-host-address--so-tickle-me>
	<871t6x14kq.fsf@gnu.org>
	<CAJ=RwfYuBrd59gaLR6W+3trOPo75zgaxKzEXVR8Xe1xKXQsg5Q@mail.gmail.com>
	<CAJ=RwfZkmQ6=SrQCs0Oy0n5KSNomh3=aU0XZtKvLJdARG7LQcw@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
Return-path: <guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org>
Received: from eggs.gnu.org ([2001:4830:134:3::10]:56260)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <ludo@gnu.org>) id 1akEav-00071k-ET
	for guix-devel@gnu.org; Sun, 27 Mar 2016 13:35:22 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <ludo@gnu.org>) id 1akEaq-00082Z-NY
	for guix-devel@gnu.org; Sun, 27 Mar 2016 13:35:21 -0400
In-Reply-To: <CAJ=RwfZkmQ6=SrQCs0Oy0n5KSNomh3=aU0XZtKvLJdARG7LQcw@mail.gmail.com>
	(David Thompson's message of "Sat, 26 Mar 2016 16:53:39 -0400")
List-Id: "Development of GNU Guix and the GNU System distribution."
	<guix-devel.gnu.org>
List-Unsubscribe: <https://lists.gnu.org/mailman/options/guix-devel>,
	<mailto:guix-devel-request@gnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/archive/html/guix-devel>
List-Post: <mailto:guix-devel@gnu.org>
List-Help: <mailto:guix-devel-request@gnu.org?subject=help>
List-Subscribe: <https://lists.gnu.org/mailman/listinfo/guix-devel>,
	<mailto:guix-devel-request@gnu.org?subject=subscribe>
Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org
Sender: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org
To: "Thompson, David" <dthompson2@worcester.edu>
Cc: guix-devel <guix-devel@gnu.org>

"Thompson, David" <dthompson2@worcester.edu> skribis:

> On Sat, Mar 26, 2016 at 2:33 PM, Thompson, David
> <dthompson2@worcester.edu> wrote:
>> On Sat, Mar 26, 2016 at 2:23 PM, Ludovic Court=C3=A8s <ludo@gnu.org> wro=
te:
>>> David Thompson <dthompson2@worcester.edu> skribis:
>>>
>>>> * tests/guix-environment-container.sh: Remove obsolete test.
>>>
>>> [...]
>>>
>>>> -if guix environment --bootstrap --container \
>>>> -     --ad-hoc bootstrap-binaries -- kill -SEGV 2
>>>> -then false;
>>>> -else
>>>> -    test $? -gt 127
>>>> -fi
>>>
>>> This test was added in light of <http://bugs.gnu.org/21958>.  We want to
>>> make sure we don=E2=80=99t lose that property.
>>>
>>> What happens exactly when a signal is sent to PID 1?  I would expect
>>> that its parent process, which is outside the container in a waitpid
>>> call, would simply get its exit value in the normal way, and thus,
>>> changing =E2=80=9C2=E2=80=9D to =E2=80=9C1=E2=80=9D in this test should=
 do the trick.  Am I na=C3=AFve?  :-)
>>
>> The problem is that a process within the container cannot just kill
>> PID 1 since its the init process and the kernel protects it, so
>> changing "2" to "1" doesn't work.  The exit status of the environment
>> command is 0 in that case because PID 1 never received the signal and
>> thus exits normally.
>>
>> I'll try to come up with a replacement test case, thanks for giving me
>> the context in which it was added.  (I should've used 'git blame'
>> first.)
>
> Coming up with a replacement test has proved very difficult.  Since
> PID 1 is unkillable, I'm having a hell of time coming up with a clever
> way to kill a Guile process via a signal.

Would it help to change the test to:

  guix environment --bootstrap --container \
     --ad-hoc bootstrap-binaries -- sh -c 'exec kill -SEGV 2'

essentially mimicking previous behavior?

Ludo=E2=80=99.