Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932312AbWLRX7a (ORCPT ); Mon, 18 Dec 2006 18:59:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932358AbWLRX7a (ORCPT ); Mon, 18 Dec 2006 18:59:30 -0500 Received: from smtp.osdl.org ([65.172.181.25]:60770 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932312AbWLRX73 (ORCPT ); Mon, 18 Dec 2006 18:59:29 -0500 Date: Mon, 18 Dec 2006 15:59:18 -0800 (PST) From: Linus Torvalds To: Paul Mackerras cc: Alexandre Oliva , Ricardo Galli , linux-kernel@vger.kernel.org Subject: Re: GPL only modules In-Reply-To: <17799.10706.834077.676728@cargo.ozlabs.ibm.com> Message-ID: References: <200612161927.13860.gallir@gmail.com> <17799.10706.834077.676728@cargo.ozlabs.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2223 Lines: 51 On Tue, 19 Dec 2006, Paul Mackerras wrote: > > There is in fact a pretty substantial non-technical difference between > static and dynamic linking. If I create a binary by static linking > and I include some library, and I distribute that binary to someone > else, the recipient doesn't need to have a separate copy of the > library, because they get one in the binary. I agree, and I do agree that it's a real difference. I personally think that it's the "aggregation" issue, not a "derivation" issue, but I'll freely admit that it's just my personal view of the situation. > In other words, static linking gives the recipient a "free" copy of > the library, but dynamic linking doesn't. That is why some companies' > legal guidelines have quite different rules about the distribution of > binaries, depending on whether they are statically or dynamically > linked. Yes. There is not doubt at all that regardless of anything else, if you link statically, you at the VERY LEAST need to have the right to distribute the library as part of an "aggregate work". > So therefore I don't think you can reasonably claim that static > vs. dynamic linking is only a technical difference. There are clearly > other differences when it comes to distribution of the resulting > binaries. Yes. And I have actually talked about this exact issue - even in the absense of any "derivation" from the library, the fact that static linking includes a _copy_ of the library does mean that you have to have the right to distribute that particular copy. Now, under the GPL, aggregate distribution is allowed, but you still do need to follow the other GPL rules (ie you would need to distributed sources for the library - even if you don't necessarily distribute sources to the binary you linked _with_). So there's no question that "dynamic linking" simplifies issues, by virtue of not even distributing any library code at all. I absolutely agree about that part. Linus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/