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From: "Casper Ti. Vector" <caspervector@gmail.com>
To: supervision@list.skarnet.org
Subject: Re: Update on the progress of slew development
Date: Wed, 20 Mar 2019 19:51:34 +0800	[thread overview]
Message-ID: <20190320115134.GA14073@CasperVector> (raw)
In-Reply-To: <20190320051439.GA7636@CasperVector>

On Wed, Mar 20, 2019 at 01:14:39PM +0800, Casper Ti. Vector wrote:
> Fixed (provided that sysvinit killall(8) is included in the container)
> in commit 3f246b20 the day before yesterday :)

I forgot to note that sending SIGHUP is unnecessary, and `rc.halt' did
this previously because of my misunderstanding of how the catch-all
logger was stopped.  `s6-svc -X /run/service/s6-svscan.log' lets the
corresponding `s6-supervise' process immediately close its fds 0/1/2 and
wait to exit after the catch-all logger exits, so the logger's input is
only connected to outputs of unlogged services (except for itself) not
stopped in `rc.fin' (which should not exist if `s6-rc -d change ...'
succeeded) and all stray processes that has inherited fds from parents
that directly wrote to the catch-all logger.

If no such processes remained at this moment, the SIGHUP (intended to
stop the catch-all logger because it is started with the `-b' option of
`s6-log') would have no effect; if they existed, sending SIGHUP
immediately after SIGTERM/SIGCONT would probably result in lost logs for
the final outputs of them, and simply letting the impending SIGKILL kill
the logger would be better.  Additionally, I have just realised that
these final logs were not considered by the current version of
`rc.halt', and then pushed commit 5911f892 to fix this.

> something like
> : /bin/importas PIA PIA
> : /usr/bin/env -i PATH=/usr/sbin:/usr/bin:/sbin:/bin PIA=${PIA}

Note that here correctness of the environment is ensured whether $PIA is
non-empty, empty or unset, because in the last case `importas' would
simply delete `PIA=${PIA}' from the command line to be exec()ed.  (Kudos
to Laurent, of course :)

-- 
My current OpenPGP key:
RSA4096/0x227E8CAAB7AA186C (expires: 2020.10.19)
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  reply	other threads:[~2019-03-20 11:51 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-03-17 13:25 Casper Ti. Vector
2019-03-17 14:30 ` Oliver Schad
2019-03-18 14:44   ` Casper Ti. Vector
2019-03-19 12:10     ` Casper Ti. Vector
2019-03-19 12:42   ` Casper Ti. Vector
2019-03-19 15:25     ` Casper Ti. Vector
2019-03-19 15:58     ` Oliver Schad
     [not found]       ` <20190320051439.GA7636@caspervector>
2019-03-20  5:14       ` Casper Ti. Vector
2019-03-20 11:51         ` Casper Ti. Vector [this message]
2019-05-04  6:07         ` Casper Ti. Vector
2019-05-05  1:55           ` race condition in killall sysinit
2019-05-07 14:46             ` Casper Ti. Vector
2019-05-11 18:29             ` Guillermo
2019-05-11 19:26               ` Laurent Bercot
2019-09-27 17:42 ` Update on the progress of slew development Casper Ti. Vector

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