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Opening SC from external application.

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josue_vf
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Opening SC from external application.

Post by josue_vf »

Hi:

I am interested in using SC to support my commercial application. I am aware that the license terms do not allow me to bundle my software with SC but, does it allow me to launch it at the click of a button from my application (if present on the host's hard drive?).

Also, is it OK to provide a direct download link to SC from my application?. The files would be hosted on our own server.

Thanks.
B
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Re: Opening SC from external application.

Post by B »

I'm not a lawyer (or a VNC developer/copyright owner) but I think you are perfectly able to bundle UltraVNC, or any GPL program, on your distribution media so long as (a) you provide or offer to provide source code for UltraVNC, (b) you do NOT link your code to its code or create a derived product in such a way that your (presumably closed source) program violates the terms of the license, and (c) you otherwise respect the terms of the software.

In brief, as long as the programs are completely separate in function, I don't think there's a problem?

(Of course, making your program GPL too makes the issues go away anyway.)
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supercoe
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Re: Opening SC from external application.

Post by supercoe »

B,

From my understanding you cannot bundle your closed source program with GPL code/binaries. They must remain "at arms length".
http://www.gnu.org/licenses/gpl-faq.html
I'd like to incorporate GPL-covered software in my proprietary system. Can I do this?
You cannot incorporate GPL-covered software in a proprietary system. The goal of the GPL is to grant everyone the freedom to copy, redistribute, understand, and modify a program. If you could incorporate GPL-covered software into a non-free system, it would have the effect of making the GPL-covered software non-free too.
A system incorporating a GPL-covered program is an extended version of that program. The GPL says that any extended version of the program must be released under the GPL if it is released at all. This is for two reasons: to make sure that users who get the software get the freedom they should have, and to encourage people to give back improvements that they make.

However, in many cases you can distribute the GPL-covered software alongside your proprietary system. To do this validly, you must make sure that the free and non-free programs communicate at arms length, that they are not combined in a way that would make them effectively a single program.

The difference between this and “incorporating” the GPL-covered software is partly a matter of substance and partly form. The substantive part is this: if the two programs are combined so that they become effectively two parts of one program, then you can't treat them as two separate programs. So the GPL has to cover the whole thing.

If the two programs remain well separated, like the compiler and the kernel, or like an editor and a shell, then you can treat them as two separate programs—but you have to do it properly. The issue is simply one of form: how you describe what you are doing. Why do we care about this? Because we want to make sure the users clearly understand the free status of the GPL-covered software in the collection.

If people were to distribute GPL-covered software calling it “part of” a system that users know is partly proprietary, users might be uncertain of their rights regarding the GPL-covered software. But if they know that what they have received is a free program plus another program, side by side, their rights will be clear.

josue_vf,
Doing what you said seems reasonable to me.
http://www.chunkvnc.com - ChunkVNC - Free PC Remote control with the Open Source UltraVNC wrapper InstantSupport!
B
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Re: Opening SC from external application.

Post by B »

But supercoe, I think that's exactly what I said. The OP <b>is</b> keeping the programs at arm's length. All he wants is to make sure you install UltraVNC SC. He's not modifying anything or creating a derived product combining his code with UltraVNC's.

Your second bolded paragraph ("in many cases you can distribute") seems, to me, to fit exactly the scenario described.

I do not think the OP is proposing combining the programs "so that they become effectively two parts of one program".

I don't think it's any different than an open source (or freeware or shareware) compilation disk. As long as they have permission to distribute, and long as the programs are merely the installers (or in the case of GPL programs, installers with GPL license and possible source code), each individual program's license continues to be respected.

Here's something I found at http://www.stromian.com/Book/Chap6.html

The most common myth is that getting too close to GPL’d software will cause proprietary software to be lost forever to its owners. Actually, it takes the compilation of GPL’d software with other software to require that the resultant derivative product be distributed under the GPL.


<b>There is no obstacle to distributing GPL’d software on the same disk with proprietary software.</b>

Sigh. Or maybe I'm wrong? ffmpeg gets pretty crazy about this

https://roundup.ffmpeg.org/issue1162

But even then, I <b>think</b> one is still allowed to distribute ffmpeg with closed source products.
what we want: ffmpeg sources (plus patches, plus any
configuration/build scripts) for each ffmpeg/mplayer
that mediacoder distributed as required by gpl/lgpl.
Last edited by B on 2010-07-22 15:08, edited 1 time in total.
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supercoe
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Re: Opening SC from external application.

Post by supercoe »

Sorry B, I didn't mean to come off like OP was doing something wrong which is why I said "Doing what you said seems reasonable to me."
I just wanted to point out the "arms length" issue I read about so he knows.

With the new info you just posted I'm even more confused now about how the whole thing works. :P

I say the heck with it all and just go by Googles "Don't be evil" motto.

0:-)
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B
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Re: Opening SC from external application.

Post by B »

Oh, okay... I was gong by your "cannot bundle your closed source program with GPL code/binaries" which seemed wrong. Depending on what "bundle" means.

Who knows. I started to think that maybe his "launch" button might violate things but I <b>really</b> don't think so? I mean, that's like saying you can't have a menu system that launches programs with different licenses.

And THIS is why I'm neither a lawyer NOR a developer! :)
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JDaus
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Re: Opening SC from external application.

Post by JDaus »

B wrote:And THIS is why I'm neither a lawyer NOR a developer! :)
LOL

As far as i understand it, you can provide the GPL product on the same installation media as the proprietary product, and you can link to it on installation of either product, but they cannot reside INSIDE the same installer ... that is not keeping them "at arms length" (to use the phase above)

take a look at the UVNC server installer ... it downloads the proprietary mirror drivers and vista functions, and i am fairly sure this is done so it doesn't break GPL ... another app example is CutePDF, which downloads a opensource ghostscript interpreter upon install ...

so if its OK by the majority of applications that use GPL / proprietary code in the same product, then linking to UVNC SC from within your app, will surely not break the GPL license (fingers crossed - my cousin is the lawyer, not me, but thats my 2c worth)

Jim
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don't ask, and remain a fool for life - JDaus 2003

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B
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Re: Opening SC from external application.

Post by B »

Oh, okay, that's a useful frame of reference -- the downloading from remote Internet site during installation is analogous to "downloading" from the local media (disk, USB, etc.) on which the main installation program is co-resident. So in this case, "Internet" roughly equals "distribution media".

...which makes sense. :)

Thanks.
Last edited by B on 2010-07-26 14:18, edited 1 time in total.
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