From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Lars Ingebrigtsen Newsgroups: gmane.emacs.bugs Subject: bug#17036: Continuation for Emacs: invoking a process on exit? Date: Sun, 17 Apr 2022 16:49:42 +0200 Message-ID: <8735ib933t.fsf@gnus.org> References: <874n2v9l10.fsf@igel.home> <874k2saqjh.fsf@gnus.org> <83y203yla1.fsf@gnu.org> <87fsmbap4e.fsf@gnus.org> <83wnfnyjkg.fsf@gnu.org> <87wnfn98oc.fsf@gnus.org> <83sfqbydvi.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="12876"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) Cc: rgm@gnu.org, 17036@debbugs.gnu.org, schwab@linux-m68k.org, rrt@sc3d.org To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Sun Apr 17 16:51:04 2022 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ng6Ey-00039Y-2d for geb-bug-gnu-emacs@m.gmane-mx.org; Sun, 17 Apr 2022 16:51:04 +0200 Original-Received: from localhost ([::1]:34956 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ng6Ew-000758-HH for geb-bug-gnu-emacs@m.gmane-mx.org; Sun, 17 Apr 2022 10:51:02 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:43582) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ng6Dy-00074s-9M for bug-gnu-emacs@gnu.org; Sun, 17 Apr 2022 10:50:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:42982) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1ng6Dx-0003QE-V0 for bug-gnu-emacs@gnu.org; Sun, 17 Apr 2022 10:50:01 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1ng6Dx-0002K6-Qv for bug-gnu-emacs@gnu.org; Sun, 17 Apr 2022 10:50:01 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Lars Ingebrigtsen Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sun, 17 Apr 2022 14:50:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 17036 X-GNU-PR-Package: emacs Original-Received: via spool by 17036-submit@debbugs.gnu.org id=B17036.16502069988917 (code B ref 17036); Sun, 17 Apr 2022 14:50:01 +0000 Original-Received: (at 17036) by debbugs.gnu.org; 17 Apr 2022 14:49:58 +0000 Original-Received: from localhost ([127.0.0.1]:36879 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ng6Du-0002Jl-GL for submit@debbugs.gnu.org; Sun, 17 Apr 2022 10:49:58 -0400 Original-Received: from quimby.gnus.org ([95.216.78.240]:43568) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ng6Ds-0002JY-Rh for 17036@debbugs.gnu.org; Sun, 17 Apr 2022 10:49:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnus.org; s=20200322; h=Content-Type:MIME-Version:Message-ID:In-Reply-To:Date: References:Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=hDCZDeXHS+PAa5sc+WCCqBJu3htEH9VxM88fQjDaPBE=; b=dg01g1aNSdmIg1mL9aGVrrsqs1 Ta8tFrRbwZE9xh3824VdZ2G2hVZatbAaL/1WbjnSJj88gITDRhqj4bkR2o5cW/AGdOGf9kdMD6/G1 GpjVxIQgZVgiJBVSmksElB+rCi1xB6P+KrtuHXwOXh7wSeX4vnnW7kzLwUJqk68/DW58=; Original-Received: from [84.212.220.105] (helo=xo) by quimby.gnus.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ng6Df-0006US-Ri; Sun, 17 Apr 2022 16:49:48 +0200 In-Reply-To: <83sfqbydvi.fsf@gnu.org> (Eli Zaretskii's message of "Sun, 17 Apr 2022 17:37:53 +0300") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:230067 Archived-At: Eli Zaretskii writes: >> > . the exit status of the restarted Emacs is discarded, so it will >> > not be available to the parent program, at least on MS-Windows, >> > and also if execvp fails for some reason; >> >> Again, Emacs doesn't exit, so... > > I meant when the restarted Emacs exits. It _can_ exit, can't it? If you exit from the new process, then you'll get the exit code from that next call to `kill-emacs'? >> I thought we opened all file descriptors with CLOEXEC? If not, that's a >> bug, since we'd be leaking file descriptors to programs we start with >> `call-process', for instance. > > What about stadin/stdout/stderr etc.? Those are inherited, I think. (Which is good.) >> > . does the restarted Emacs belong to the same process group? should >> > it? >> >> I think so, and I guess so? > > Is that guaranteed? should we make sure it's so? Or is it > unimportant? I think that whatever the OS does here by default is what's correct, so it's not something we need to worry about. >> Sounds like we should just document that this doesn't work on Windows, >> then. > > It works now, at least in the GUI sessions. Great! > Some other questions related to this: > > . AFAIU, the execvp'ed process inherits the environment of the > calling process, so any changes to the environment will be > propagated to the child, right? Do we want that? I'm not quite sure. We could save envp and call execve instead with that saved envp (I think?), but I think using the environment is what we want here. Probably? But perhaps that should be an option... > . What about the working directory? If the original Emacs was > invoked with --chdir, the restart happens in another directory; > moreover, relative program name in argv[0] and relative directory > name in --chdir may not work. Is that a problem? Ah, yes it is. --chdir and relative names stops this from working, so that needs fixing, I think. > . What should happen to client frames when Emacs is restarted? What > does happen with the current implementation, .e.g if some of the > client frames are on other displays? I expect those to disappear. We're restarting Emacs, after all. -- (domestic pets only, the antidote for overdose, milk.) bloggy blog: http://lars.ingebrigtsen.no