License change possible?

[einSelbst]

Hi, would you mind update the license to GPLv3 or or license it as "GPLv2 or any later version"?
In our frontend project it's basically the only library which comes with GPLv2 from more than 1500 packages. Unfortunately GPLv2 doesn't play well with Apache2, at least the lawyers say so.

[einSelbst]

I also had a look at Peter Selinger's website, which is linked from your readme and found this:

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version.

[iwsfg]

Sorry that it took me well over a month to reply

License change is a difficult topic to me. I'm no lawyer and I don't have full confidence that doing so is okay. Underneath it's still a port of original Potrace so keeping the same license as original seems to be the most logical thing to me.

And if it wasn't for that clause from GPLv2 text I'm pretty sure I wouldn't even be in position to do so.

I also had a look at Peter Selinger's website, which is linked from your readme and found this:

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version.

But this text is indeed included in the code of the program itself as the license text suggests, so I guess it counts and we're technically allowed to transition to a newer version of the GPL license. Also in this case nothing is stopping you from forking this project and releasing it under the GPLv3 as well as far as I can tell.

I had time to think what would be the best approach and since switching licenses would be a breaking change of sort for anyone currently using it in the projects licensed under GPLv2 I think it should be done carefully. If I'm gonna do this it would be nice to first do some general maintenance, update dependencies and make sure that last version released under GPLv2 will stay nice and usable for the next few years. Then do the license change and release a new major version under GPLv3.

Sorry if this is not the outcome you were hoping for.

[iwsfg]

would you mind [...] license it as "GPLv2 or any later version"?

Oh, yeah, I should probably do this for you to be able to fork and release under newer license. This "any later version" clause is still present in the LICENSE file but not included as a comment in any of the source files in this repo nor it is explicitly says so in the License section of README.md.

@tooolbox and @kilobtye as this project includes a ton of code written by you I think I should ask for your approval of this. You don't mind if I change it to "GPLv2 or later", do you?

[tooolbox]

@iwasawafag I am totally fine with this. The code I actually wrote compared to @kilobtye was small, so I think it's mainly his decision.

[einSelbst]

Oh, yeah, I should probably do this for you to be able to fork and release under newer license. This "any later version" clause is still present in the LICENSE file

Hi and thanks for your answer. Actually, I think if you just officially "GPLv2 or any later version" it, which as mentioned would match the licensing from Peter Selinger, all issues would be resolved because it would allow users to license it as GPLv3. It wouldn't be necessary to fork and re-license it then.