I wrote to the OSI mailing list back then and asked to approve "giftware" as another open source license, but they refused and basically told me our license is public domain and not a license. Seems that mailing list doesn't exist anymore, but parts of my thread somehow made it into google nevertheless:

http://zork.net/~nick/mail/we-could-ask-lawrence-lessig-if-only-he-werent-such-a-git

I think we added the disclaimer section since then, so now things are a little bit different. I guess our license basically is MIT/BSD now.

Anyway, about addons which are licensed under MIT/BSD, there should be no problem. Source distributions are no problem anyway (unless we include code from another library into Allegro itself), and for binary distributions - it will be a good idea anyway to list in our docs what other libraries we use, and there we can also add any required copyright notice or disclaimers if it's demanded by the license. Even using LGPL libraries should be no problem that way (at least if we use only shared linking.. I remember something about that..).

For binary distributions, we could also make an extra document which should be included with games using Allegro (in case they re-distribute any of those third-party libraries or use an Allegro version which statically links them in).

Changing the license would require asking all developers of code we currently have if its ok to change it, and getting permission from ALL said developers, or removing or replacing their code if we can't other wise reach them or get their consent.

Hmm... but after you did that, their code would no longer be under the giftware license, so that you effectively say "these people originally said you could do anything with their code, but we now tell you otherwise." That does seem a bit odd.
Then again, the original code would still be available under the old license. How does dual licensing work? Can we tell people that they can use Allegro either under the giftware license or under the BSD license, say?

Careful. "No license at all" would mean that anyone using Allegro is violating the copyright holders' copyrights, as they haven't been given a licence to use the code in Allegro.

I would support licensing Allegro 4.9/5 under a MIT/BSD licence.

Might be a good idea. I'll put in a vote for the MIT license.

They're all decent. Here are the clauses:

The last two clauses in the BSD license are optional; if you remove both of them you basically end up with the MIT license again.

It depends a bit on whether we want the license to state that people have to acknowledge Allegro, or whether we trust people to do that without us requiring it (more or less as we do now, and something I thing most people would do if they think about it).

I also support dropping giftware for A5. Reading the three licenses above, ZLIB sounds like the best one to me. They key point is "If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.". I.e. if I make a game, then it is up to me if I want to mention somewhere that Allegro was used or not. (Of course, if I use A5 addons which use/depend on MIT or BSD or even LGPL code, I at least have to mention those somewhere in small print in the docs anyway.. so probably it wouldn't matter.)

I'm fine with all three of those licenses.. don't know if I could pick a favorite. I usually go with BSD for my own code.

We should also specify some place that ALL new contributions are licenced the same, and the "entity" that is the "dev team" has all rights to contributed code in the future.

Course I'm not sure we can do the last bit without an actual legal entity taking ownership (there is an opensource group that will do it for a project that can't afford or isn't big enough to set up their own legal organization).

Ok, doing that now

I don't care about Google Code per se; leave it aside.

There's a growing concern about licence proliferation in the free software world and there seems to be a push to "cull" (figuratively) the lesser known or redundant licences. MIT/BSD are the traditional representatives of the "permissive free software licenses" and obviously much more popular than zlib. They won't be on the wrong side of the "cull".

Now, zlib is closer in spirit to giftware and (probably) has better wording than either BSD or MIT, but the only practical difference I can see is attribution. Given all the considerations:

- wanting a standard licence
- not wanting to contribute to licence proliferation
- not wanting to end up with a marginalised licence

I'm wondering if the difference between zlib and BSD/MIT is really great enough to justify it.

Just wondering...

Why does it matter how many licenses exist? Just curious.

They tend to be incompatible with each other, and that introduces confusion.

I agree totally with what PW said. I'd pick between MIT/BSD.

No, he doesn't mean exclusive. You could personally license your code under the GPL, but give Allegro 5 a copy under (e.g.) BSD.

If somebody uses the code from you, then they'll be stuck with GPL. But if they get the code from Allegro, they get BSD. This distinction matters if the Allegro developers go on to improve your code... then those improvements are BSD and you cannot claim it (exclusively) as GPL.

However, if you make independent changes to your GPL code, the Allegro people cannot take it from you, unless you explicitly give them permission.