Selling GNU general public license software

[silmaril]

ZITAT(MartinD @ Aug 6 2007, 03:52 PM)

In general if I was to download LabVIEW code from the repository and use it in my application that I intend to sell over & over that seems OK. Referring to the GNU GENERAL PUBLIC LICENSE.

Yep. That's correct as I understand it, too.

ZITAT(MartinD @ Aug 6 2007, 03:52 PM)

But while the terms a conditions start off quite well it seems to become more restrictive towards the end. If I sell an installer that puts an exe on a windows system do I really need to have an about box that reads "WITHOUT ANY WARRANTY" etc?

Yes, you must meet certain conditions that make it clear that your work is under the GPL.

Don't forget: If you use GPL code, your complete work must be under the GPL as well!

ZITAT(MartinD @ Aug 6 2007, 03:52 PM)

And supply the end user with the source code (VIs). Firstly I would like to provide a warranty with the software and secondly I think my cutomers would have little use for VI's. Other than that am I missing anything major?

I'm not 100% percent shure about this one.

As I understand it, the users must have some way to get the source code. You don't need to ship it with every installation, it should be enough to have them downloadable on a server.

If you want to provide a warranty: just go ahead! You can do this without breaking the GPL.

ZITAT(MartinD @ Aug 6 2007, 03:52 PM)

Until now I have avoided the use of any code repositry VIs in my application that I intend to sell but to be honest thats becoming a bit of a pain now, I'm wasting hours

Just to be shure: Are we really talking about GPL here, or rather about some libraries that are under the LGPL?

If it's LGPL, then it's much easier. You don't need to publish your own source code in this case and your application doesn't need to be under the LGPL itself.

You still have to deliver the LGPL license text with your software and make clear what you are using, but I think that's just fair.

[MartinD]

QUOTE(silmaril @ Aug 6 2007, 03:11 PM)

Yep. That's correct as I understand it, too.

Yes, you must meet certain conditions that make it clear that your work is under the GPL.

Don't forget: If you use GPL code, your complete work must be under the GPL as well!

I'm not 100% percent shure about this one.

As I understand it, the users must have some way to get the source code. You don't need to ship it with every installation, it should be enough to have them downloadable on a server.

If you want to provide a warranty: just go ahead! You can do this without breaking the GPL.

Just to be shure: Are we really talking about GPL here, or rather about some libraries that are under the LGPL?

If it's LGPL, then it's much easier. You don't need to publish your own source code in this case and your application doesn't need to be under the LGPL itself.

You still have to deliver the LGPL license text with your software and make clear what you are using, but I think that's just fair.

Thanks for that information.

We are talking about GPL here. Basically my application uses ImageMagick extensivley, that's covered by some license "compatible with GPL". Now with the advent of the LAVA code repositry "LVOOP ImageMagick Interface" I'm tempted to use that also. That's covered by the GNU GPL version 2 license.

You said: Don't forget: If you use GPL code, your complete work must be under the GPL as well!

This concerns me a little. There may be some parts of code I would prefer to remove the diagrams from. Those that talk to bespoke hardware etc. I wonder where the line is drawn here because I cannot provide the source code for the NI functions for example. I guess the key is "all my work" becomes covered by the GPL.

Thanks agin,

-Martin

[gb119]

QUOTE(MartinD @ Aug 6 2007, 05:30 PM)

You said: Don't forget: If you use GPL code, your complete work must be under the GPL as well!

This concerns me a little. There may be some parts of code I would prefer to remove the diagrams from. Those that talk to bespoke hardware etc. I wonder where the line is drawn here because I cannot provide the source code for the NI functions for example. I guess the key is "all my work" becomes covered by the GPL.

There is a provision in the GPL to not include things that are normally part of the operating system. In the context of LabVIEW it would have to be taken that the "operating system" included everything that was installed as part of the LabVIEW runtime engine - if the person who wrote the GPL'd LabVIEW code hasn't or can't make this implicit extension to the OS exception then it is unclear whether you can redistribute their GPL code at all.

You can distribute code under the GPL with the diagrams stripped or protected, but you'd have to include someway of acessing the source code - i.e. the vi's with the diagrams unprotected and editable. In which case, why bother protecting it ? There's no way round that - it's just how the GPL works.

[silmaril]

ZITAT(MartinD @ Aug 6 2007, 06:30 PM)

We are talking about GPL here. Basically my application uses ImageMagick extensivley, that's covered by some license "compatible with GPL". Now with the advent of the LAVA code repositry "LVOOP ImageMagick Interface" I'm tempted to use that also. That's covered by the GNU GPL version 2 license.

You said: Don't forget: If you use GPL code, your complete work must be under the GPL as well!

This concerns me a little. There may be some parts of code I would prefer to remove the diagrams from. Those that talk to bespoke hardware etc. I wonder where the line is drawn here because I cannot provide the source code for the NI functions for example. I guess the key is "all my work" becomes covered by the GPL.

Are you really using ImageMagick's source code in your application?

Then you have to make your work GPL as well.

But it sounds as if you are only writing some application that invokes ImageMagick. I don't think you have to make your programm open source in this case.

I am not shure, if you are allowed to include the ImageMagick installer in your own installer.

Seeing how this is handled in other projects, you might need to deliver it as two separate installers and your users must install both of them separately.

[Tomi Maila]

QUOTE(silmaril @ Aug 7 2007, 12:37 PM)

Are you really using ImageMagick's source code in your application?

Then you have to make your work GPL as well.

Actually ImageMagick is not GPL. It's some proprietary license that may be compatible with GPL meaning that ImageMagick can be used in a GPLed project. However it's not a GPL license and hence you may not need to GPL your project at all. If ImageMagick would be of GPL license, then you would need to GPL all derivative work which in this case would mean your library.

[MartinD]

QUOTE(silmaril @ Aug 7 2007, 10:37 AM)

Are you really using ImageMagick's source code in your application?

Then you have to make your work GPL as well.

But it sounds as if you are only writing some application that invokes ImageMagick. I don't think you have to make your programm open source in this case.

I am not shure, if you are allowed to include the ImageMagick installer in your own installer.

Seeing how this is handled in other projects, you might need to deliver it as two separate installers and your users must install both of them separately.

Thank you for pointing this out to me.

Basically I'm just invoking ImageMagick via the command line. So if this means I can get away from making my software open source, that would be my favoured option. But it does mean I can not use the LVOOP ImageMagick code that is now available, fair enough I suppose. Back to spending hours re-coding what already exists I guess...

QUOTE(Tomi Maila @ Aug 7 2007, 10:41 AM)

Actually ImageMagick is not GPL. It's some proprietary license that may be compatible with GPL meaning that ImageMagick can be used in a GPLed project. However it's not a GPL license and hence you may not need to GPL your project at all. If ImageMagick would be of GPL license, then you would need to GPL all derivative work which in this case would mean your library.

I'm going to try and avoid GPL'ing my product in this case I think. I should read the ImageMagick proprietary license again, but I'm often not really sure after reading all those conditions. Maybe after a few reads it will sink-in!

Thanks