From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: wait_reading_process_ouput hangs in certain cases (w/ patches) Date: Mon, 13 Nov 2017 18:00:40 +0200 Message-ID: <83y3nakw2f.fsf@gnu.org> References: <83lgjz8eiy.fsf@gnu.org> <831slp98ut.fsf@gnu.org> <83tvyj62qg.fsf@gnu.org> <83r2tetf90.fsf@gnu.org> <5150d198-8dd3-9cf4-5914-b7e945294452@binary-island.eu> <83tvy7s6wi.fsf@gnu.org> <83inemrqid.fsf@gnu.org> <398f8d17-b727-d5d6-4a31-772448c7ca0d@binary-island.eu> <83bmk6n9hs.fsf@gnu.org> Reply-To: Eli Zaretskii NNTP-Posting-Host: blaine.gmane.org X-Trace: blaine.gmane.org 1510588879 12010 195.159.176.226 (13 Nov 2017 16:01:19 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 13 Nov 2017 16:01:19 +0000 (UTC) Cc: ml_emacs-lists@binary-island.eu, emacs-devel@gnu.org To: Paul Eggert Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon Nov 13 17:01:15 2017 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eEHAZ-0002bb-Oo for ged-emacs-devel@m.gmane.org; Mon, 13 Nov 2017 17:01:07 +0100 Original-Received: from localhost ([::1]:55121 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eEHAh-0005Wp-7s for ged-emacs-devel@m.gmane.org; Mon, 13 Nov 2017 11:01:15 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:53712) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eEHA9-0005Wj-4N for emacs-devel@gnu.org; Mon, 13 Nov 2017 11:00:42 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eEHA3-0000nQ-Hh for emacs-devel@gnu.org; Mon, 13 Nov 2017 11:00:41 -0500 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:60281) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eEHA3-0000n9-75; Mon, 13 Nov 2017 11:00:35 -0500 Original-Received: from [176.228.60.248] (port=1670 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1eEHA2-0005WJ-KI; Mon, 13 Nov 2017 11:00:35 -0500 In-reply-to: (message from Paul Eggert on Sun, 12 Nov 2017 21:27:05 -0800) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:4830:134:3::e X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:220142 Archived-At: > Cc: ml_emacs-lists@binary-island.eu, emacs-devel@gnu.org > From: Paul Eggert > Date: Sun, 12 Nov 2017 21:27:05 -0800 > > >>> + if (wait_proc > >>> + && wait_proc->infd_num_bytes_read != initial_wait_proc_num_bytes_read) > >>> + got_some_output = 1; > >> Similarly for the other change that assigns to got_some_output. > > You can read up-thread why I'm firmly against doing that. > > It doesn't explain why you're so firm about it since the commentary clearly > states that 1 is OK I explained that as well. In a nutshell, I see no reason to consider our commentary the definitive documentation of what the code does. It is much more probable that either the commentary was never accurate, or it was once, but the code was modified without updating the comments. IME with Emacs sources, code reading is a much more reliable way of figuring out what a function does than relying on its commentary. > but at any rate one could use this instead: > > if (wait_proc) > { > unsigned int diff = (wait_proc->infd_num_bytes_read > - initial_wait_proc_num_bytes_read); > if (diff != 0) > got_some_output = diff; > } > > which is still a bit simpler than what was proposed. I'm okay with that, but it looks like an stylistic issue, so I wouldn't insist on that.