X-Spam-Check-By: sourceware.org Date: Tue, 26 Dec 2006 12:21:29 -0500 From: Christopher Faylor To: cygwin@cygwin.com Subject: Re: Updated cygwin dlls cause unnecessary reboot on NT Message-ID: <20061226172129.GA10452@trixie.casa.cgf.cx> Reply-To: cygwin@cygwin.com Mail-Followup-To: cygwin@cygwin.com References: <458EE598.3010404@aim.com> <458F31B1.6050804@byu.net> <458F81CC.3090500@tlinx.org> <458FDC4E.9040505@cygwin.com> <458FEC2E.70705@tlinx.org> <45902BC4.50803@tlinx.org> <4590BD4E.5020905@cygwin.com> <45910426.9030603@tlinx.org> <459133CB.3080102@ukf.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <459133CB.3080102@ukf.net> User-Agent: Mutt/1.5.11 Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: 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 On Tue, Dec 26, 2006 at 02:38:03PM +0000, Max Bowsher wrote: >Linda Walsh wrote: >> The fix I proposed has nothing to do with the cygwin1.dll. As has >> been covered previously, since cygwin1.dll and a few other libs are >> part of the cygwin "kernel", special handling may be needed to upgrade >> those dll's. What can be fixed is the installation of .exe and .dll >> files for >> applications. The behavior of those should be the same as replacing >> in-use .so's and executables on *nix. > >I believe there is a critical element you have missed. > >In order to perform the rather miraculous emulation of fork(), Cygwin >needs to reload all the same DLLs that are operating in one process into >another newly created process. Updating the DLL files on disk whilst >processes are using them prevents this from happening. > >For a simple demonstration of this: > >* Start a bash shell >* Rename any of the DLLs used by bash to something else >* Try to execute any non-builtin command >* See the fork failure message > >Could this be worked around? Perhaps. >Is it likely to happen? No, the benefit-to-work ratio is too low. Thanks for adding a piece of the puzzle, Max. This is a reason why just renaming an in-use dll is not going to work and creation of .new files is required. cgf -- 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/