Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Delivered-To: mailing list cygwin@cygwin.com Mime-Version: 1.0 (Apple Message framework v622) In-Reply-To: <20050527202823.GB4939@trixie.casa.cgf.cx> References: <44f83c19cc33e4382680fe3758164ccf@rehley.net> <20050527202823.GB4939@trixie.casa.cgf.cx> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Message-Id: <0833be552ca5aa00a72ecef822250580@rehley.net> From: Peter Rehley Subject: Re: pthreads, cygwin and pthread_mutex_lock not blocking Date: Fri, 27 May 2005 16:35:39 -0700 To: cygwin@cygwin.com X-IsSubscribed: yes Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by delorie.com id j4RNZo91006408 On May 27, 2005, at 1:28 PM, Christopher Faylor wrote: > On Fri, May 27, 2005 at 10:57:34AM -0700, Peter Rehley wrote: >> I'm trying to use pthread in cygwin, and I'm expecting the function >> pthread_mutex_lock to block when used. However it is returning error >> 45 (EDEADLK). I'm using a static initializer for the thread so the >> mutex is type PTHREAD_MUTEX_DEFAULT. >> When I look through the pthread code I see that PTHREAD_MUTEX_DEFAULT >> is set to PTHREAD_MUTEX_ERRORCHECK, >> When I do the same on linux or soloris, the pthread_mutex_lock blocks, >> and looking in the pthread.h file on those systems see that the >> default is set to PTHREAD_MUTEX_NORMAL. >> >> Why is cygwin using PTHREAD_MUTEX_ERRORCHECK as the default? And what >> problems might occur if PTHREAD_MUTEX_DEFAULT is set to >> PTHREAD_MUTEX_NORMAL? > > Why not just try it and report the results? Done. Hangs at WaitForSingleObject. The application that I'm working on is rpm 4.3.3, the problem that we are seeing is running scripts. When set the default is set to ERRORCHECK, the parent process doesn't wait and removes the script before the child has chance to run it. When default is NORMAL, the parents hangs waiting for the child. The app uses SIGCHLD to signal the parent when the child dies, and the signal handler for sigchld releases the mutex. This should cause the WaitForSingleObject to release and the application should continue to run. For whatever reason, the signal isn't being seen by the parent. Enjoy, Peter ------------------------------- A Møøse once bit my sister -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/