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diff --git a/iphone/doc/licensing.rst b/iphone/doc/licensing.rst new file mode 100644 index 0000000..075ccd4 --- /dev/null +++ b/iphone/doc/licensing.rst @@ -0,0 +1,187 @@ +Licensing the Library +===================== + +First of all, the big disclaimer: + +.. warning:: + + We are *not* lawyers; we cannot help you decide if you should use the + library or how to apply the license, only your lawyer can advise you + concerning legal matters. + +That said, it should also be noted that we have neither the resources (time, +cash, etc) nor the patience to enforce the license (at all); the reality is +that all of this is left to your discretion. + +If you prefer to leave the lawyers out of it, the rest of this section will +help you apply the license to your application. + + +Licensing FAQ +------------- + +Can I use this library with my proprietary (closed source) application? + Yes, that is our intent and we do not believe there is any problem + regarding the license. + +Will I need to open source my entire app? + No, it is not required by the license. + +Will I need to distribute all of my "object files" on the App Store? + No, this is also not required by the license, although you should offer to + provide them upon request. See below for more detail. + +But I read somewhere that "iPhone apps may not use LGPL code"? + That statement is an over-generalization that does not apply in this case. + Most likely your source is either: + + * referring to the GPL, which is significantly different from the + *L*\ GPL + * referring to a different version of the LGPL; we intentionally use + version 2.1, which has specific static linking exceptions. + * not a lawyer either and too lazy to read the whole license + + Basically, if you leverage the appropriate sections of the license, it + should be fully compatible with the App Store restrictions and + requirements. + +This is too complicated, can I just pay for an easier license? + No, it is not possible. There are multiple problems with this approach, + some brief highlights: + + * Most open source projects (including this one) do not have a single + author. Tracking down every contributor and getting their approval could + be quite a challenge. + * The license is meant to protect users' rights to the software. Giving + you special treatment bypasses the protection we offered them, + effectively revoking their rights. This would be a violation of their + trust and completely defeats the purpose of the license. + + You may think of this as the "price" you pay for using our open source + library. If you want to make your life easier, you should be petitioning + Apple for shared library support... + +What if you add a clause that lets me do whatever I want? + No, also not possible. In addition to the problems mentioned above, there + are even more problems with this: + + * Sourceforge requires an OSI approved license for hosting our project; + an altered license would no longer be approved. + * Again we are not lawyers and therefore not qualified to change the + license, we would have to pay one of those slimy buggers to do it. + +Do I need to add an "about" dialog to display your copyright/license? + No, not as such. We won't discourage you from plugging the library if you + like, but it is not a requirement. You should think of our license as a + supplement to your own software license, therefore it is appropriate to + display it where (and only where) you display your own: + + * If you follow Apple's recommendation, the App Store is the only place + that the user accesses your license, so it should also be the only place + where the library supplement is available. + * If your app already has some kind of "about" view that displays your + copyright/license information, it is also appropriate to display the same + information for the library. + +Do I need to include the entire library in my application bundle? + No, it is not necessary: + + * If you have not modified the library, it is sufficient to provide a link + to the project and the version information. + * If you are using a modified version, you may provide a link to download + that instead of including it in the bundle. + + +Modifications +------------- + +What is a "modification"? Again, we leave it to your discretion with this +guidance: + +* If you use the distributed binary SDK you have certainly not modified the + library. +* If you are working from Mercurial, *any* change you have made to the + "source code" of the library is a modification, it does not matter how + trivial. You can see what changes have been made by running + ``hg status -mard``; if this command outputs anything, you have modified + the library. + +If you find that you have made changes to the library, you should carefully +consider how far you want to proceed down that path. Once you publish your +changes you have created a "fork" of the project which you now need to +maintain. Are you prepared to merge every time the library is updated? + +If your change adds a useful feature to the library, we absolutely encourage +you to submit patches. Assuming you can get your patch into the project, then +you will no longer need to use a modified version! When submitting patches, +ensure that your changes are appropriate for all of our users. Specifically, +we are not interested in patches that simply hack up the library to work the +way you want. Compare a patch that changes the default behavior to your +preference (probably not acceptable), to a patch that adds a new configuration +to support the feature you have added (probably fine). + + +Object File Distribution +------------------------ + +Section 6 of the LGPL v2.1 specifically permits static linking with the +library. If your project is not open source, this section does require that +you make your object files available to your users. The intent, as indicated +in the license, is that a user who has obtained your software may exercise +their right to modify the library and then re-link their modified version into +your application. + +We recommend that you apply Subsection 6c, which only requires that you make a +written offer to provide the object files. Now...if you consider the actual +utility of this mechanism - that it is only applicable to developers, and only +those with in depth knowledge of the tools, the time required for development +- all to have a new barcode reader in a specific version of your application +that only they can use, the reality is that no one is going to request this. +You probably should not even waste time preparing for it until a request is +made. + +Additionally, to avoid "casual requests" from nefarious types that just want +to inconvenience you, also consider charging a fee for the distribution of +this material (as permitted by the license); just add up the cost of burning +and shipping a disk. If this cost is "large" compared to the price of your +app, the likelihood of a request is reduced even further. + + +Using the Unmodified Library +---------------------------- + +Applying the license in this case is somewhat simpler. These are the basic +steps you can follow: + +1. Verify that the rest of your software license is compatible with the LGPL. + You cannot use the library if they are incompatible. + + For those using the default App Store license, we have reviewed this and + believe it is compatible with the LGPL. + +2. At the end of your license text, in an annex or supplement, start by + declaring your use of the library and offering a link to the project. + Something like this: + + This software uses the open source ZBar Barcode Reader library, version + |version|, which is available from http://zbar.sourceforge.net/iphone + + If you built your own version of the library, replace the version callout + with eg, "cloned from Mercurial revision xxxxxxxx" + +3. Then append the contents of the text file COPYING, included with the + library. This is all of the copyright information for the library. + +4. Then append the contents of the text file LICENSE.md, also included with the + library. This is just the LGPL version 2.1 which you may also obtain from + http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html + +5. You may choose to make the written offer for the object files explicit. + Provide some text and whatever link or email address is appropriate. + + +Using a Modified Library +------------------------ + +We intentionally leave this option vague and force you to refer to the license +as an underhanded way of encouraging you to contribute back to the project ;) |