* Claus-Peter Wiedemann: > If APIs were to be copyrightable, it would have a huge impact, > especially for the C/C++/Linux world. In that universe, APIs are > usually defined in header files containing type definitions (data > structures) and function signatures. In order to use software > (e.g. a library) with such API, you will have to include the header > file into your code. If the API is copyrightable and the > library+header file are licensed, say, under LGPL, your code would > need to be licensed under (L)GPL, too. This would be the end of > proprietary applications using LGPL libraries.
In the LGPL case, the library copyright owner gives explicit permission to link the library with proprietary applications, under certain circumstances. Copyright infringement by programming to an API would not alter how the LGPL impacts applications, I think. Stronger, more restrictive copyright laws are not a problem for the GNU licenses, they benefit from it. I've been concerned for a long time that this provides too much of an incentive to free software advocates to demand Draconian interpretations of copyright law. In the beginning, copyright on software was immoral, but now an ever-expanding scope of copyright law is welcomed as an enforcement tool. I still consider copyleft an important statement, but I'm not sure how the practical implementation will play out in the long run.
