From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Richard Stallman Newsgroups: gmane.emacs.devel Subject: Re: QNX subprocess bug Date: Sat, 25 Mar 2006 19:22:02 -0500 Message-ID: References: Reply-To: rms@gnu.org NNTP-Posting-Host: main.gmane.org Content-Type: text/plain; charset=ISO-8859-15 X-Trace: sea.gmane.org 1143332567 16662 80.91.229.2 (26 Mar 2006 00:22:47 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Sun, 26 Mar 2006 00:22:47 +0000 (UTC) Cc: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Mar 26 01:22:44 2006 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by ciao.gmane.org with esmtp (Exim 4.43) id 1FNJ1j-0003wA-3b for ged-emacs-devel@m.gmane.org; Sun, 26 Mar 2006 01:22:39 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1FNJ1i-0006G9-F6 for ged-emacs-devel@m.gmane.org; Sat, 25 Mar 2006 19:22:38 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1FNJ1J-0006FO-9U for emacs-devel@gnu.org; Sat, 25 Mar 2006 19:22:13 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1FNJ1I-0006Ev-1N for emacs-devel@gnu.org; Sat, 25 Mar 2006 19:22:12 -0500 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1FNJ1H-0006Ep-Nm for emacs-devel@gnu.org; Sat, 25 Mar 2006 19:22:11 -0500 Original-Received: from [199.232.76.164] (helo=fencepost.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.52) id 1FNJ2R-0004qF-Gc for emacs-devel@gnu.org; Sat, 25 Mar 2006 19:23:23 -0500 Original-Received: from rms by fencepost.gnu.org with local (Exim 4.34) id 1FNJ18-0005Lx-JR; Sat, 25 Mar 2006 19:22:02 -0500 Original-To: Bob Bramwell In-reply-to: (message from Bob Bramwell on Sat, 25 Mar 2006 05:34:04 +0000 (GMT)) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:52060 Archived-At: The bug is showing up in emacs 21.2.1 on QNX 6.3.0. It appears that process IDs on QNX really occupy 32-bits. Some of them are quite large. This causes a problem in the subprocess package which uses an elisp integer (28 bits + type info - I think) to try to store the PID. Obvious this problem could, in principle, arise on any system that uses 32-bit process IDs, and it seems to me rather sloppy programming to use such a shortcut, especially in such comparatively rarely executed code. It is not a short cut. The reason the pid is represented as a Lisp integer is that (1) all the slots in a process object have to be Lisp objects, and (2) Emacs has no way to deal with integer values larger than a Lisp integer. It will not be easy to fix this problem. Since QNX support is not a high priority for GNU, I think it is up to you to implement the fix. But since there is no obvious way to fix it, first you'd need to work out a way that would not cause too much problem in Emacs.