Thread: Qt now LGPL

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  2. #2
    Cat without Hat CornedBee's Avatar
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    Excellent!
    All the buzzt!
    CornedBee

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    Frequently Quite Prolix dwks's Avatar
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    I think it's kind of funny that Qt was originally QPL'd, and then they allowed it to be GPL'd, and now it's LGPL'd.
    dwk

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    Woof, woof! zacs7's Avatar
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    Too late, already loyal to Gtk+

  5. #5
    & the hat of GPL slaying Thantos's Avatar
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    Quote Originally Posted by dwks View Post
    I think it's kind of funny that Qt was originally QPL'd, and then they allowed it to be GPL'd, and now it's LGPL'd.
    Hopefully they'll improve it again and go with a freer (is that a word?) license like BSD or MIT

  6. #6
    Malum in se abachler's Avatar
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    Thats nice, LGPL open it up to be profitable to devlop for, without paying royalties, so thats a good thing versus only beign GPL. I think LGPL also allows you to keep proprietary modifications secret.

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    Cat without Hat CornedBee's Avatar
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    Nope, it doesn't. That's what makes it different from the BSD license. (And that you can generally hide that you're using something BSD-licensed. With the LGPL, you have to point it out and be able to provide the source of the LGPL thing.)
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    CornedBee

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    Great news!

    (I didn't even know it's now owned by Nokia...)

  9. #9
    Malum in se abachler's Avatar
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    Quote Originally Posted by CornedBee View Post
    Nope, it doesn't. That's what makes it different from the BSD license. (And that you can generally hide that you're using something BSD-licensed. With the LGPL, you have to point it out and be able to provide the source of the LGPL thing.)
    No, I'm pretty sure you can roll LPGL code together with proprietary code without the proprietary code becoming open source. I looke dinto this for a previous employer and even wrote the FSF about it. GPL code however is viral in that anything it is used with also becomes open source.

    I could be mistaken however...

  10. #10
    & the hat of GPL slaying Thantos's Avatar
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    What LGPL requires is that you provide the source for the LGPL licensed components. I assume from CornedBee's comment (and from my experience it seems correct) that you'd also have to state which LGPL components you are using.

    So lets say you've got LGPL package XYZ that is statically linked to your proprietary code. You've got to let people know you are using XYZ and provide the source.

    Just a though about providing the source: I wonder if it is enough to provide a link to the XYZ project page that has the source.

    Actually people should just use the http://en.wikipedia.org/wiki/WTFPL license

  11. #11
    Cat without Hat CornedBee's Avatar
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    Quote Originally Posted by abachler View Post
    No, I'm pretty sure you can roll LPGL code together with proprietary code without the proprietary code becoming open source. I looke dinto this for a previous employer and even wrote the FSF about it. GPL code however is viral in that anything it is used with also becomes open source.

    I could be mistaken however...
    You can create proprietary programs that link against LGPL stuff without having to open-source your proprietary stuff. That's the difference between the LGPL and the GPL.

    However, when you said modifications above, I assumed you meant modification to the LGPL thing itself, which you can't do.
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    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
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  12. #12
    Officially An Architect brewbuck's Avatar
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    Quote Originally Posted by CornedBee View Post
    You can create proprietary programs that link against LGPL stuff without having to open-source your proprietary stuff. That's the difference between the LGPL and the GPL.
    True, but you either have to dynamically link, or provide object files for your product so that the end user can drop in a different version of the LGPL library.

    In almost any commercial product that's going to be unacceptable for a number of reasons. First and foremost, if the user can change code from underneath your application, how can you possibly support it? You never know if the bug being reported is actually in your app, or if it came from some stupid change the user made to the LGPL component.

    LGPL is mostly a pipe dream. I've never seen a piece of commercial software that actually used an LGPL component.
    Code:
    //try
    //{
    	if (a) do { f( b); } while(1);
    	else   do { f(!b); } while(1);
    //}

  13. #13
    Cat without Hat CornedBee's Avatar
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    No commercial GTK+ apps out there?
    All the buzzt!
    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
    - Flon's Law

  14. #14
    Malum in se abachler's Avatar
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    Quote Originally Posted by brewbuck View Post
    LGPL is mostly a pipe dream. I've never seen a piece of commercial software that actually used an LGPL component.
    Ive used LGPL graphics libraries in commercial video processing applications before.

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