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NoRulez
23rd January 2009, 09:18
Hi,

did anybody know what i must include, when i want to sell a written program, beside executeable, libraries and documentation? ;-)

I want when i sell the program that this is legal

Much thanks
NoRulez

wysota
23rd January 2009, 09:53
The licence. And you should include the sources or information about means of (physically) acquiring them if your application is open source.

seneca
23rd January 2009, 12:53
If you bought a commercial Qt license before you started developing, then you are free to sell at whatever license or conditions you want.

Second option is to provide the all sources and sell your application under GPL license. Since it may be passed on free you probably won't sell too many copies.

Third you can wait until Qt 4.5 and then sell under whatever license you want, need not provide your own source code. But you need to add a LGPL license notice about Qt then, along with information where Qt sources can be downloaded. You are also not allowed to statically link Qt to your code in this case.

wysota
23rd January 2009, 15:30
Third you can wait until Qt 4.5 and then sell under whatever license you want, need not provide your own source code.
This is not true. It's LGPL, not public domain, you have to obey the terms of the licence.

seneca
23rd January 2009, 16:27
This is not true. It's LGPL, not public domain, you have to obey the terms of the licence.

Please read the LGPL again, thats exactly the difference between GPL and LGPL.

Of course you must obey LGPL license for the Qt libraries that you distribute together with your software. You can however sell your own code which is using the LGPL libraries unter whatever license you want.

wysota
23rd January 2009, 22:42
I know what the difference is but reducing it to "you can do whatever you want" is simply not true. You can do whatever you want provided you don't break Qt's LGPL licence. The fact that Qt will be licenced under LGPL doesn't mean you can do with it whatever you want. For instance the licence demands you can substitute the LGPL-licenced component with another one of the same functionality. So stripping it down to "you can't static link Qt" is not enough. Remember you can configure Qt with different options, you can patch it with some code and finally that Qt depends on 3rd party libraries itself as well. You have to consider all that when deciding if you do or do not violate Qt's licence. Of course you are true that you can release your software on any licence you want (with addition that it doesn't forbid the use of LGPL components).

Note that I'm not against the idea behind your post, just against the words (and impression one might have after reading them) you used.

seneca
24th January 2009, 00:46
I never stated that - you pulled a single sentence out of context and claimed it to be false.

Discussion at this level leads to nowhere, bye.

wysota
24th January 2009, 01:05
I claimed it not to be true, and not to be false, there is something inbetween - you might call it an incomplete truth. I just know how not-entirely-true statements or assumptions lead to false conclusions. Please don't be offended, I never meant that.

I didn't pull anything out of the context, by the way, as the context itself was just right above my post. My reply was related to a particular sentence of your post, thus I quoted only that sentence.

seneca
24th January 2009, 08:02
I just summed up the three basic options you have with theire main constraints. That does of course not describe all the license issues into detail, so still you need to read the licenses yourself, and in case ask you lawyer for advice.

Sorry for not pointing that out in first place, I thought it would be obvious.

Brandybuck
26th January 2009, 20:18
Commercial proprietary: include executable, Qt libraries, documentation. That should be it. See the "Deploying Qt" pages in Assistant.

Open Source GPL: You application needs to be released under an approved license (GPL, BSD, MPL, etc). In addition you need to make your own source code and that of Qt available. This doesn't have to be included with the executables, but it needs to be available to the user. Typically this is done by putting it on an FTP site, including documentation on how to obtain it, etc.

Open Source LGPL (v4.5): Include executable, Qt libraries, documentation, and make the source code of Qt available (doc on how to obtain it should be fine). You can license your own code however you want. But please not that if you use static linkage, or modify Qt itself, then you will have additional requirements and should treat the Qt license as being GPL instead.

wysota
26th January 2009, 21:13
Typically this is done by putting it on an FTP site, including documentation on how to obtain it, etc.

I read somewhere (I think the link was provided here on the forum in the other thread regarding LGPL) that if you don't include the source code with the executable, you have to make it possible to physically obtain the sources (i.e. send them via snail-mail on a CD) and you have to continue doing that for three more years after you stop distributing your software. I also read there is a clause (or just an unwritten rule) that non-commercial applications are freed from the "physical" part of providing the sources and can use the Internet for that.

NoRulez
27th January 2009, 15:18
Commercial proprietary: include executable, Qt libraries, documentation. That should be it. See the "Deploying Qt" pages in Assistant.

Thank you for your answer, this is what i search for ;-)

Regards
NoRulez

giusepped
2nd February 2009, 04:53
I read this long post, and I would ask you to check if I well understood the problem.
Suppose that I would like to earn something by selling my software.
I donwloaded Qt Open Source.
Which one of the following point is correct
1) I ask a fee for downloading the exe but I do not distribute the source code
2) I ask a fee for downloading both the exe and the source code
3) Both exe and source code are freely downloadable and GPL.

The not-said thing beside these questions is that I would sell the software I did but without buying the commercial license, for lack of money (now).
Is it possible?
Thanks in advance

seneca
2nd February 2009, 09:34
Why don't you read the GPL, LGPL and Qt commercial licenses yourself? It will give you exactly the information you need. If something still is unclear, ask GNU and Nokia for theire opinions.

Nobody here will be able to give you a legal advice you could base your business on.

wysota
2nd February 2009, 10:04
Are you asking about your code or Qt? :)