4 ms·

> If your software is making some money using QT6, you will have to pay. Otherwise you can happy use the LGPL License Nope, you can make a commercial closed-so

> If your software is making some money using QT6, you will have to pay. Otherwise you can happy use the LGPL License Nope, you can make a commercial closed-source application that links against LGPL-licensed library. Also, the source code model has nothing to do with "making money". For example, Qt is certainly "making money" with their source code, but did you know that the WebView component in Qt is actually COPIED from Apple's Safari WebKit source code? Yes! So they are STEALING Apple LGPL source code and making money with it! And what more, Apple Safari certainly runs on iPhones and Apple if someone is certainly making some big $$$! You seem to have misunderstood what changed. No, Qt did not change the licensing terms to charge for "making money" with Qt. They just made more of their previously free support functions exclusive to paying licensees.

djsumdog 6y ago
> Nope, you can make a commercial closed-source application that links against LGPL-licensed library. So in this case, you'd have to package the software so it doesn't include Qt (in an RPM/deb) so it pulls in the system Qt? Or on Windows, provide them a link so they can download that component manually?
- cxr 6y ago
  Almost every comment in this thread against the subscription licensing model is addressing a legitimate issue. This comment is not—it's misinformation/FUD. That's not how the LGPL works. The cavalier attitude of people who just utterly make up bullshit, like what's in the comment above, is something that we should have a lot less tolerance for.
  - fiddlerwoaroof 6y ago
    I always forget exactly what is permissible with the LGPL, but isn’t it the case that the whole point is that using a LGPL library doesn’t “infect” your program?
    - stjohnswarts 6y ago
      Generally it means you can't (in this case) mess with the Qt Libraries, you use them as is, and link to them dynamically. You do NOT have to release your source code, however you do have to provide Qt source (libraries) to anyone who requests them from you to whom you "have distributed" your software to (paid or unpaid), whether you provided a download link or DVD or usb drive, etc. If you someone received your software outside of your distribution channel you can tell them to go pound sand though since you didn't distribute to them directly and they got a copy through some other means.
- toyg 6y ago
  No. It just means you have to ship Qt unmodified and provide sources to Qt on request.
  - djsumdog 6y ago
    oh .... well then what's the point of a commercial license? You'd only need it if you customize the original Qt source code and don't use it as-is, right? Or if you want support beyond forums/mailing lists?
    - toyg 6y ago
      Yes, but customizing and patching is not that uncommon for commercial software (Qt is used a lot in the embedded space, for example, where patching and shaving away is common). Also, businesses do pay for support as insurance; say tomorrow Windows patches something that screws up a bit of Qt your product depends on, what are you going to do? Waiting for a reply on a random mailing list and hoping someone has time to fix it, is not going to cut it.
    - stjohnswarts 6y ago
      As usual support and there are some libraries in the Qt Umbrella of source code that ARE NOT LGPL and you can't use those for distribution unless you pay for the commercial license.

djsumdog 6y ago

> Nope, you can make a commercial closed-source application that links against LGPL-licensed library. So in this case, you'd have to package the software so it doesn't include Qt (in an RPM/deb) so it pulls in the system Qt? Or on Windows, provide them a link so they can download that component manually?

cxr 6y ago
Almost every comment in this thread against the subscription licensing model is addressing a legitimate issue. This comment is not—it's misinformation/FUD. That's not how the LGPL works. The cavalier attitude of people who just utterly make up bullshit, like what's in the comment above, is something that we should have a lot less tolerance for.
- fiddlerwoaroof 6y ago
  I always forget exactly what is permissible with the LGPL, but isn’t it the case that the whole point is that using a LGPL library doesn’t “infect” your program?
  - stjohnswarts 6y ago
    Generally it means you can't (in this case) mess with the Qt Libraries, you use them as is, and link to them dynamically. You do NOT have to release your source code, however you do have to provide Qt source (libraries) to anyone who requests them from you to whom you "have distributed" your software to (paid or unpaid), whether you provided a download link or DVD or usb drive, etc. If you someone received your software outside of your distribution channel you can tell them to go pound sand though since you didn't distribute to them directly and they got a copy through some other means.
toyg 6y ago
No. It just means you have to ship Qt unmodified and provide sources to Qt on request.
- djsumdog 6y ago
  oh .... well then what's the point of a commercial license? You'd only need it if you customize the original Qt source code and don't use it as-is, right? Or if you want support beyond forums/mailing lists?
  - toyg 6y ago
    Yes, but customizing and patching is not that uncommon for commercial software (Qt is used a lot in the embedded space, for example, where patching and shaving away is common). Also, businesses do pay for support as insurance; say tomorrow Windows patches something that screws up a bit of Qt your product depends on, what are you going to do? Waiting for a reply on a random mailing list and hoping someone has time to fix it, is not going to cut it.
  - stjohnswarts 6y ago
    As usual support and there are some libraries in the Qt Umbrella of source code that ARE NOT LGPL and you can't use those for distribution unless you pay for the commercial license.