X-Recipient: archive-cygwin@delorie.com X-Spam-Check-By: sourceware.org Date: Wed, 1 Jul 2009 11:11:56 -0400 From: Christopher Faylor To: cygwin@cygwin.com Subject: Re: fork and exec (was: Re: Proposed patch to system.XWinrc) Message-ID: <20090701151156.GB335@ednor.casa.cgf.cx> Reply-To: cygwin@cygwin.com Mail-Followup-To: cygwin@cygwin.com References: <416096c60906302255t1b5bdb41u442ebca20679c8d9@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <416096c60906302255t1b5bdb41u442ebca20679c8d9@mail.gmail.com> User-Agent: Mutt/1.5.19 (2009-01-05) 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 Wed, Jul 01, 2009 at 06:55:35AM +0100, Andy Koppe wrote: >2009/6/23 Christopher Faylor: >>>If posix_spawn() ever gets implemented in Cygwin to >>>avoid the slowness of fork(), /bin/sh might well change to the first >>>shell that supports it. >> >> It's really somewhat of an urban myth about Cygwin's fork being slow. >> Cygwin's exec is also pretty slow. ??I'm not really sure that posix_spawn >> would cause any kind of performance improvement. > >Ah, right. So is it Windows' CreateProcess() itself that's slow? Or is >it some of the additional stuff that exec() needs to deal with? >Signals? The hidden console? The majority of the exec code is in spawn.cc - spawn_guts(). You can see for yourself that this is not a simple function. Just remember that neither fork nor exec have native Windows analogues. cgf -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple