From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.comp.sysutils.supervision.general/2933 Path: news.gmane.io!.POSTED.ciao.gmane.io!not-for-mail From: "Serge E. Hallyn" Newsgroups: gmane.comp.sysutils.supervision.general Subject: Re: Readiness notification exemplars Date: Sat, 4 Apr 2020 10:48:51 -0500 Message-ID: <20200404154851.GC698@mail.hallyn.com> References: <20200401142122.GA30742@mail.hallyn.com> <20200401152832.GA31205@mail.hallyn.com> <20200401162600.GA31582@mail.hallyn.com> <2771eb82-9e19-06a7-d15c-28633971d8b2@NTLWorld.COM> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202"; logging-data="100443"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Mutt/1.9.4 (2018-02-28) Cc: Supervision To: Jonathan de Boyne Pollard Original-X-From: supervision-return-2522-gcsg-supervision=m.gmane-mx.org@list.skarnet.org Sat Apr 04 17:48:54 2020 Return-path: Envelope-to: gcsg-supervision@m.gmane-mx.org Original-Received: from alyss.skarnet.org ([95.142.172.232]) by ciao.gmane.io with smtp (Exim 4.92) (envelope-from ) id 1jKl2T-000PtO-VE for gcsg-supervision@m.gmane-mx.org; Sat, 04 Apr 2020 17:48:54 +0200 Original-Received: (qmail 25557 invoked by uid 89); 4 Apr 2020 15:49:19 -0000 Mailing-List: contact supervision-help@list.skarnet.org; run by ezmlm Original-Sender: Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Original-Received: (qmail 25550 invoked from network); 4 Apr 2020 15:49:19 -0000 Content-Disposition: inline In-Reply-To: <2771eb82-9e19-06a7-d15c-28633971d8b2@NTLWorld.COM> Xref: news.gmane.io gmane.comp.sysutils.supervision.general:2933 Archived-At: On Fri, Apr 03, 2020 at 07:41:25AM +0000, Jonathan de Boyne Pollard wrote: > Serge E. Hallyn: > > > If making changes to daemons were going to palatable, [...] > > > > Clearly, it *is* palatable, given that a few people have been adding the > systemd mechanism to their programs for several years, now. Pierre-Yves Well both that and the less successfull upstart sigstop had the full force of popular distros behind them. Still I hope you're right, and maybe I'll go ahead and post some patches for a few daemons. > Ritschard's code and Cameron Norman's code come straight out of actual > service programs. > Serge E. Hallyn: > > > you are arguing for parsing stdout for a text message and/or using > > pidfiles (written to an fd) > > > > No, M. Bercot is not. Quite the opposite, in fact. The s6 readiness > mechanism demands *neither* pidfiles *nor* standard output. It's *any* file > descriptor (as defined by the service), and *just a linefeed* followed by > closing the descriptor. > > I'm nodding at almost everything M. Bercot is saying here, by the way. > > * http://jdebp.uk./FGA/unix-daemon-readiness-protocol-problems.html Yes it sounds like I completely misread the earlier emails, sorry about that. Now, looking at http://skarnet.org/software/s6/notifywhenup.html, I'm probably not reading that quite right, but it seems to tie the proposal to the 'notifcation-fd' file in the service directory, making it a bit less general. s6-log however uses the -d argument to pass the fd, so I'll go with that. thanks, -serge