[winswitch] [Xpra] Android client

Jakub Księżniak jksiezniak at gmail.com
Wed Jun 24 13:47:09 BST 2015


Thanks for all feedback. I've read a bit about licensing and I came up with
some thoughts.

1. To write a fully functional client application, a network protocol must
be implemented to communicate with other side. In this case, the only
available reference is a source code of Xpra and wiki pages.
2. Unfortunately the documentation found on the wiki is not sufficient, as
for example I had to learn from Java sample code what capabilities must be
sent in a Hello packet in order to connect to the server. Without it, it's
impossible to get a reasonable response, not to mention about other
3. If the Xpra protocol was described in some official document like
RFC6143 for the RFB protocol, then I could base on it instead of the Xpra

To sum up, it appears that my code is a "derived work" and thus the only
option is to choose a GPL license. :-(

Then, I'll change license information on Github with my next commit.

Jakub Księżniak
23 cze 2015 10:02 "Antoine Martin" <antoine at nagafix.co.uk> napisał(a):

> Hi,
> On 22/06/15 22:47, Jakub Księżniak wrote:
> > Hello,
> >
> > I've been writing an Android Xpra client for some time now (maybe you
> > remember our previous conversation on a mailing list). It took me quite a
> > lot of time to make a barely working app, but here it is. :) You can
> > download source code from Github and build it by yourself:
> > https://github.com/jksiezni/xpra-client
> Good stuff!
> I think this should replace the current "official" Android client, which
> was never more than a quick and dirty proof of concept.
> > Moreover, I've got some concerns regarding licensing. I'd like to share
> my
> > code on terms of Apache License 2.0 and I'd like to know if it is OK with
> > you.
> This is not entirely up to me and IANAL.
> My understanding is that if you've developed your code using a "clean
> room design", then you can use any license you want for your code.
> Otherwise, you probably fall under the "derived work" and therefore are
> bound by the GPL.
> I did write a lot of information on the wiki to try to make it easier to
> implement new clients without referring to the actual code (though most
> of it may be slightly out of date), starting here:
> http://xpra.org/trac/wiki/NetworkProtocol
> To make matters more complicated: although I would be quite happy to
> re-license all of my code under a different license, which would cover
> 100% of the Java client for example (assuming you read some code and
> that this is what you used)... but then again, by definition (since I
> wrote a large portion of the GPL2+ xpra code) not using a "clean room
> design", I don't think I could re-license it under anything less
> restrictive than the GPL. And even if this was possible, I'm not sure
> you could apply it retroactively - but maybe?
> And it also depends what jurisdiction you fall under... etc.
> > Also, I've added an Xpra icon to the android project, which makes an app
> > much more recognizable. But it requires your permission, if I'm not
> > mistaken. So, do you agree, to use the Xpra icon in this project?
> No problem from me here... this icon is a bit too close to the official
> X11 icon, and I should probably have sought permission from them...
> I just wanted to get something done quickly, many years ago, and did not
> foresee the project getting as successful as it is now.
> The project also covers a lot more than just plain-X11 servers now, so
> this may be a good time to come up with a better icon?
> (there are also requirements for 1024x1024 to get into the Apple appstore)
> > Any feedback would be appreciated.
> I'm hoping others can chime in, hopefully with more experience in this
> area.
> Cheers
> Antoine
> PS: Some pointers:
> https://en.wikipedia.org/wiki/Clean_room_design
> http://hoviblog.blogspot.fr/2008/10/clean-room-defeats-software.html
> " For purposes of proving such a claim of copyright or trade secret
> misappropriation, it is not necessary to prove that actual copying
> occurred. It is sufficient to show that (1) the accused party had access
> to the code, and (2) the accused party's code is substantially similar
> to the claimant's code."
> I have no idea what "substantially similar" means here!
> >
> > Regards,
> > Jakub Księżniak
> > _______________________________________________
> > shifter-users mailing list
> > shifter-users at lists.devloop.org.uk
> > http://lists.devloop.org.uk/mailman/listinfo/shifter-users
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