X-Recipient: archive-cygwin AT delorie DOT com DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:date:from:to:subject:message-id:reply-to :references:mime-version:content-type:in-reply-to; q=dns; s= default; b=EGlIFM9pfDLvadmRwFAaNnSuYMH231+xQAXJVJk1e4WqUsoxX2kgG rLj05z7/AometU94DUBZc5ytOuJ1UnDf4q7IaO50haS//lacLKI5VeM6HVs2AvLG uJd8pyr5LY6+f4m8AUE22EMNGjA0j80Kzl7UQwCEX4LudHkoHWXp3g= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:date:from:to:subject:message-id:reply-to :references:mime-version:content-type:in-reply-to; s=default; bh=cIVZLSpPZoxU0/N1Rmx0/KC0Amc=; b=J/e4XgXFfeOHUl9GSiRlzwED5Di5 T0FPq8gUyAAqedNrFHnF0aSWwg1mMu0BOpeolrQ1GKNHBl4tcjhzUJT99IkPxkDZ mnPRudNFUVJXvabRvncR4DjfsOA6BlwkFTOMVtGG+Z750q5Tv/tb9PLAhi34rmH8 9ADxvC5MH825LOU= Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com X-Spam-SWARE-Status: No, score=-1.7 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,RCVD_IN_HOSTKARMA_YE autolearn=ham version=3.3.1 X-Mail-Handler: Dyn Standard SMTP by Dyn X-Report-Abuse-To: abuse AT dyndns DOT com (see http://www.dyndns.com/services/sendlabs/outbound_abuse.html for abuse reporting information) X-MHO-User: U2FsdGVkX1/S9KfnKYj3uTBON6ZVC8bY Date: Wed, 19 Jun 2013 13:45:14 -0400 From: Christopher Faylor To: cygwin AT cygwin DOT com Subject: Re: Adding MSYS functionality to Cygwin Message-ID: <20130619174514.GA6071@ednor.casa.cgf.cx> Reply-To: cygwin AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com References: <51C0B08E DOT 8080900 AT etr-usa DOT com> <51C0D956 DOT 4090905 AT etr-usa DOT com> <20130619020234 DOT GA3669 AT ednor DOT casa DOT cgf DOT cx> <51C1EAA3 DOT 6040307 AT etr-usa DOT com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <51C1EAA3.6040307@etr-usa.com> User-Agent: Mutt/1.5.20 (2009-06-14) On Wed, Jun 19, 2013 at 11:30:11AM -0600, Warren Young wrote: >On 6/18/2013 20:02, Christopher Faylor wrote: >> On Tue, Jun 18, 2013 at 04:04:06PM -0600, Warren Young wrote: >>> It would be possible, though somewhat evil, for Cygwin's exec() >>> implementation to peek at the DLL dependency list of a program before >>> starting it, and from that infer whether it should automatically >>> translate paths. >> >> Cygwin already does this. It detects whether the program it is about >> to run uses the Cygwin DLL and, if not, makes decisions on how to >> handle exec. It would be relatively easy to extend this. > >Well, given that we're already paying the "peek" cost, I don't have any >objection to making exec() take longer for the native Windows case only. > >Do you know how you want to cope with my contrived "xcopy /bin a b" >example? The point of the example, of course, is that "/bin" looks like >a real, existing POSIX path, but isn't. I don't think people are getting this: *How this is implemented doesn't matter*. I'm talking about providing hooks so that an add-on MSYS dll could modify the windows command-line. Then we wouldn't care what MSYS does with the command-line since it isn't a Cygwin DLL decision. The goal is to allow a small DLL to hook into Cygwin and do whatever MSYS wants to do. Something like: callout (CO_EXEC, &command_line); Where it is expected that the command line could be modified. The "check-for-windows" code is already there. Calling out would be close to a no-op in the non-MSYS cost. Otherwise, I really don't care what it costs. I understand the objections to the way that MSYS does things. I really do. I don't like what it does, either (and I've voiced the same objections in the past) but we're willing to selectively modify Cygwin to allow it to be used as the engine that drives future MSYS development. The goal would be to collapse the fork back into Cygwin with minimal cost to the Cygwin DLL. 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