Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757047AbYAETfc (ORCPT ); Sat, 5 Jan 2008 14:35:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756364AbYAETfZ (ORCPT ); Sat, 5 Jan 2008 14:35:25 -0500 Received: from japan.chezphil.org ([77.240.5.4]:5794 "EHLO japan.chezphil.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756247AbYAETfY (ORCPT ); Sat, 5 Jan 2008 14:35:24 -0500 To: "Andreas Schwab" Cc: "Jiri Slaby" , , "Frederik Deweerdt" Date: Sat, 05 Jan 2008 19:35:09 +0000 Subject: Re: strace, accept(), ERESTARTSYS and EINTR Message-ID: <1199561709625@dmwebmail.japan.chezphil.org> In-Reply-To: References: X-Mailer: Decimail Webmail 3alpha16 MIME-Version: 1.0 Content-Type: text/plain; format="flowed" From: "Phil Endecott" X-SPF-Guess: pass Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1532 Lines: 37 Andreas Schwab wrote: > "Phil Endecott" writes: >> Andreas Schwab wrote: >>> "Phil Endecott" writes: >>>> However, there's a lot of code and I know that there are bugs in it. I >>>> just want to focus on the kernel-related issue that the strace fragment >>>> that I posted brings up: even if my user code gets completely screwed up >>>> (corrupts its stack, runs out of FDs/VM/threads etc), I don't think that I >>>> should see in the strace output that accept() has returned >>>> ERESTARTSYS. >>> >>> strace always sees the raw return value, before the signal handler is >>> executed and before the check for syscall restart is done. >> >> Yes, but I should see the real final return value in another strace output >> line before I see that thread doing something else. Correct? > > No. As far as strace is concerned the syscall has finished. Since it > isn't restarted, you won't see it again in the trace. Sorry for being dense, but what is the implication of your comment "Since it isn't restarted" ? Are you saying that the kernel isn't going to restart it and will have converted it to EINTR and returned that to user-space, and that this modified return value is not reported by strace? Phil. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/