From owner-freebsd-hackers@FreeBSD.ORG Wed Jun 9 15:50:28 2010 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 9BD93106564A for ; Wed, 9 Jun 2010 15:50:28 +0000 (UTC) (envelope-from alexander@leidinger.net) Received: from mail.ebusiness-leidinger.de (mail.ebusiness-leidinger.de [217.11.53.44]) by mx1.freebsd.org (Postfix) with ESMTP id 43F0C8FC12 for ; Wed, 9 Jun 2010 15:50:28 +0000 (UTC) Received: from outgoing.leidinger.net (pD954FA9A.dip.t-dialin.net [217.84.250.154]) by mail.ebusiness-leidinger.de (Postfix) with ESMTPSA id AD0C284400A; Wed, 9 Jun 2010 17:50:22 +0200 (CEST) Received: from webmail.leidinger.net (webmail.leidinger.net [192.168.1.102]) by outgoing.leidinger.net (Postfix) with ESMTP id 079CF514C; Wed, 9 Jun 2010 17:50:17 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=Leidinger.net; s=outgoing-alex; t=1276098618; bh=ocmJ+GwDMLlccL4ymrg+FajJpB7POADU5HliUfSOVSk=; h=Message-ID:Date:From:To:Cc:Subject:References:In-Reply-To: MIME-Version:Content-Type:Content-Transfer-Encoding; b=z9DJ7U+WxpMQTjqobEGO2Ktmvkccg0DIPKV6fqngvRM94tQOmiStPfVbOEB10b2Yl YW/jYqKRM2zWA3oSBSsBaPcy/Q6Ox+G6/0tU8Mg3lyeqdojmzOi+hiq967Wq3pkwfu rHw5QYSE6AS9AP5gqdt88QRiYLTxr1BbKPn0PgzBRVbJcPJk/Lb9WDjtrAwBefSeKK 1SwDjVOgPc+bRgJvB0ZIJYBercLdQzE/Koo/b8iDm2q+l8zg9sq0QplurGWWeaoobr Lzh8Oi3E866zEahyfXNl19jYz0Opa3bMCRTi6L62JO/gGp4dIOct777DhfiTJmjxNK WKdAwPIVPrMxg== Received: (from www@localhost) by webmail.leidinger.net (8.14.4/8.13.8/Submit) id o59FoGb4065681; Wed, 9 Jun 2010 17:50:16 +0200 (CEST) (envelope-from Alexander@Leidinger.net) Received: from pslux.ec.europa.eu (pslux.ec.europa.eu [158.169.9.14]) by webmail.leidinger.net (Horde Framework) with HTTP; Wed, 09 Jun 2010 17:50:15 +0200 Message-ID: <20100609175015.18145hz1u8arpnwo@webmail.leidinger.net> Date: Wed, 09 Jun 2010 17:50:15 +0200 From: Alexander Leidinger To: Kostik Belousov References: <20100609121453.095d92b4@kibab.com> <4C0F9394.9030202@dataix.net> <20100609132543.GI83316@deviant.kiev.zoral.com.ua> In-Reply-To: <20100609132543.GI83316@deviant.kiev.zoral.com.ua> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; DelSp="Yes"; format="flowed" Content-Disposition: inline Content-Transfer-Encoding: 7bit User-Agent: Dynamic Internet Messaging Program (DIMP) H3 (1.1.4) X-EBL-MailScanner-Information: Please contact the ISP for more information X-EBL-MailScanner-ID: AD0C284400A.A62EA X-EBL-MailScanner: Found to be clean X-EBL-MailScanner-SpamCheck: not spam, spamhaus-ZEN, SpamAssassin (not cached, score=-1.1, required 6, autolearn=disabled, ALL_TRUSTED -1.00, DKIM_SIGNED 0.10, DKIM_VALID -0.10, DKIM_VALID_AU -0.10) X-EBL-MailScanner-From: alexander@leidinger.net X-EBL-MailScanner-Watermark: 1276703425.68725@OXEOwFsM5zxTPqgcASyjeA X-EBL-Spam-Status: No X-Mailman-Approved-At: Wed, 09 Jun 2010 16:01:04 +0000 Cc: freebsd-hackers@freebsd.org, Ilya Bakulin Subject: Re: GSoC: registration of optional kernel features via sysctl: a question to the community 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: Wed, 09 Jun 2010 15:50:28 -0000 Quoting Kostik Belousov (from Wed, 9 Jun 2010 16:25:43 +0300): >> I can not think of any viable reason why one would want to "spoof" this >> when it is not available. > Many ports are doing wrong thing there, checking for run-time features at > the build-time, turning on/off some functionality depending on its > presence on the build host. We heard that "there are some ports", but we do not know a concrete example. Anyone here with a concrete example of such a port (maybe more than one)? The big question here is: what is going on at build time regarding those features? As you describe the problem, we have to make a change to the port anyway. And IMO it does not matter much if we change it to detect it at run-time (then we do not need the spoofing feature), or if we change it to look for the sysctl at build time. And the preferred way would be to detect at run-time then. What we search for is a good real-life example where spoofing a non-existing feature would be helpful. So far we where able to come up with cases where this would hurt, but not help. Bye, Alexander. -- If the master dies and the disciple grieves, the lives of both have been wasted. http://www.Leidinger.net Alexander @ Leidinger.net: PGP ID = B0063FE7 http://www.FreeBSD.org netchild @ FreeBSD.org : PGP ID = 72077137