From owner-freebsd-hackers@FreeBSD.ORG Thu Feb 8 14:51:16 2007 Return-Path: X-Original-To: freebsd-hackers@freebsd.org Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 7502916A4C0 for ; Thu, 8 Feb 2007 14:51:15 +0000 (UTC) (envelope-from youshi10@u.washington.edu) Received: from mxout5.cac.washington.edu (mxout5.cac.washington.edu [140.142.32.135]) by mx1.freebsd.org (Postfix) with ESMTP id ACB0413C478 for ; Thu, 8 Feb 2007 14:51:10 +0000 (UTC) (envelope-from youshi10@u.washington.edu) Received: from smtp.washington.edu (smtp.washington.edu [140.142.32.139]) by mxout5.cac.washington.edu (8.13.7+UW06.06/8.13.7+UW06.09) with ESMTP id l18EpABI001655 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 8 Feb 2007 06:51:10 -0800 X-Auth-Received: from [192.168.10.41] (c-67-187-172-183.hsd1.ca.comcast.net [67.187.172.183]) (authenticated authid=youshi10) by smtp.washington.edu (8.13.7+UW06.06/8.13.7+UW06.09) with ESMTP id l18Ep9r2019272 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Thu, 8 Feb 2007 06:51:10 -0800 Message-ID: <45CB38D8.1000706@u.washington.edu> Date: Thu, 08 Feb 2007 06:51:04 -0800 From: Garrett Cooper User-Agent: Thunderbird 1.5.0.9 (X11/20070122) MIME-Version: 1.0 To: freebsd-hackers@freebsd.org References: <87D4B047-DC72-427B-863F-A082C3A4E5CD@u.washington.edu> In-Reply-To: <87D4B047-DC72-427B-863F-A082C3A4E5CD@u.washington.edu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-PMX-Version: 5.3.0.289146, Antispam-Engine: 2.5.0.283055, Antispam-Data: 2007.2.8.63434 X-Uwash-Spam: Gauge=IIIIIII, Probability=7%, Report='__CT 0, __CTE 0, __CT_TEXT_PLAIN 0, __HAS_MSGID 0, __MIME_TEXT_ONLY 0, __MIME_VERSION 0, __SANE_MSGID 0, __USER_AGENT 0' Subject: Re: Trying to join an already exited pthread X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 08 Feb 2007 14:51:16 -0000 Garrett Cooper wrote: > On Feb 7, 2007, at 1:51 PM, Steve Watt wrote: > >> In , >> wrote: >>> Just wondering: >>> >>> If I was to try and join a pthread that already exited, would there >>> be an error >>> message output and/or errno set to an error value, or would a system >>> hang? >> >> Was the thread created with detach state set PTHREAD_CREATE_DETACHED or >> PTHREAD_CREATE_JOINABLE? If it was PTHREAD_CREATE_JOINABLE, has the >> thread already been joined? >> >> You should be able to join a thread that was created joinable, only once. >> If you join it again, or join a thread that was created detached, the >> results are unspecified in POSIX. There is an error status that may >> be returned, but it may do other bad things to your system. >> >> Note that pthread_join doesn't set errno; it returns an error value >> directly. I would never expect the system to hang, though the >> application >> might. If your application is hanging, make sure that you're not trying >> to call pthread_join from within a signal handler. >> >>> It this variable on Unix OSes? >> >> That the results are unspecified? No. What "unspecified" means? >> Absolutely. >> --Steve Watt KD6GGD PP-ASEL-IA ICBM: 121W 56' 57.5" / 37N >> 20' 15.3" >> Internet: steve @ Watt.COM Whois: SW32-ARIN >> Free time? There's no such thing. It just comes in varying prices... > > I asked this because I was short on time and so was the person who > asked me earlier. I'm going to try giving the pthread exit and join a > shot just to see whether or not this is true or not and then I'll report > my results to the list. > Thanks for the insight though--hopefully my results will yield a > solid positive or negative to this being a problem. > -Garrett Under Suse Linux there were absolutely no errors when I tried to do this. I'll post a code snippet later. -Garrett