GPL Not as Viral as I Thought
When I read the full text of the GNU General Public License (GPL) a number of years back, I remember coming away from it thinking that the GPL infected everything it touched. I believed that if you use GPL'd software, in any way, that your software which uses it must also be GPL, i.e. free to all with source code available. Today, a workmate convinced me otherwise. I now believe that the following paragraphs from the GPL (version 2) allow you to use a GPL'd function in non-GPL code, as long as your code is in no way derived from the GPL'd code, but just uses it to perform some sub-task of your application. Is this the correct interpretation? I don't know.
These requirements apply to the modified work as a whole. If identifiable sections of that work are not derived from the Program, and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works. But when you distribute the same sections as part of a whole which is a work based on the Program, the distribution of the whole must be on the terms of this License, whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it.
Thus, it is not the intent of this section to claim rights or contest your rights to work written entirely by you; rather, the intent is to exercise the right to control the distribution of derivative or collective works based on the Program.
In addition, mere aggregation of another work not based on the Program with the Program (or with a work based on the Program) on a volume of a storage or distribution medium does not bring the other work under the scope of this License.