Does a GPL API infect its apps?
arromdee at rahul.net
Thu Oct 21 17:19:23 UTC 1999
Now that I think about it, there's an even weirder result.
Suppose I add a function to a GPL program, and I want to dual license the
function so that it can be used with the GPL program but can also be used in
way X (where X is not permitted by GPL. For instance, "may be used as a
I add the function to the GPL program, and then I add a copyright statement
saying that the function in question is dual-licensed under GPL+X.
Now we get into semantics. If dual-licensed means "is under a single license
GPL+X whose terms mean that you can use it in either of two ways", then I
cannot do this, because functions added to the GPL'ed program must be GPL'ed.
The single license GPL+X is not GPL, so it is not allowed.
If dual-licensed means "under a single license which may be one of (GPL, X),
selected by the recipient", then every time the recipient selects X, he's
received a GPL program with an added function licensed under X--this makes me
a GPL violator depending on the whim of the recipient.
The upshot of this? If I want to send someone a GPLed program with a function
of mine, and I want the function to have additional permissions, I have to
*send them two copies of the function*. This is bizarre. (I can't even
relicense the copy they already have--that would retroactively create one of
the two above cases and thus retroactively make me a GPL violator.)
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