If my program just sometimes calls to GPL program should all my program be Open Source GPL?

Question

If my program just sometimes calls to GPL program (or if we talk about flash my swf sometimes sends parameters to other GPL'd swf) should all my program be Open Source GPL?

Answer 1

if the component are separable like a swf call another swf but that's two separate files your source don't have to be GPL.

There is also the library exception, like your program use a GPL library (linking in C), your program can be still be a closed source.

Anyway if you are using those code commercially like selling a product,I advise you to see with a lawyer probably the most wise choice.

Answer 2

Do not make business decisions based on legal advice you get on the internet -- including mine! Seek a qualified legal professional who knows something about software licensing and intellectual property.

That said, there doesn't seem to be any distinction in the GPL license for when your code "sometimes" makes calls to GPL code. So I don't think you can get away with this.

There is a Lesser GPL, which is related to the library exception @RageZ is referring to. However, unless the swf you're using is clear that it uses the LGPL or a library exception, you should assume this exception is not available to you.