A Beginner's Guide to Linux Licensing

January 2002

A Beginner’s Guide to Linux Licensing

By Shawn Gordon
CEO, theKompany.com

Second of two parts

Last month I introduced the concepts of distributions (called “distros”), desktops and other resources for HP 3000 managers looking into Linux as an alternative. This month we’ll talk about license issues in the Linux world — a subject of considerable interest, since one of the big initial attractions to Linux is the environment’s reduced cost of ownership.

It’s important to understand that Linux is the operating system kernel, and not the subsystems around it. So Linux is like MPE itself — but things like FCOPY, Query and IMAGE, these are all really add-ons to the MPE kernel. Linux uses the same kind of organization. This brings us to RMS, GNU and the GPL.

RMS stands for Richard M. Stallman, who founded the Free Software Foundation (FSF). GNU stands for Not Unix (the Linux environment is replete with silly recursive acronyms) pronounced “guh-new.” The FSF and GNU groups are the same for the most part.

In the early days the GNU group was working on a kernel called Herd. To this day it isn’t done, but a lot of that software got ported to the Linux kernel — utilities like editors, file systems, shells and things. But the GNU software makes up only a small percentage of what comes with Linux distributions these days.

I’ve found that RMS has a massive ego and I believe he is also essentially a communist (I’m not making this up, just read anything he’s written: go to www.fsf.org). He likes to insist on calling Linux “GNU/Linux” because of the environment’s GNU code, and he also likes to talk about software freedom. This is where you will hear the motto “free as in speech, not free as in beer.” That phrase means that source code should be freely distributable for people to modify and distribute, but not necessarily for no cost. It looks to me like RMS would prefer it to be a workers’ paradise, where everyone toils to the common good. This is where the GPL comes in.

The GNU group is also responsible for the GPL and LGPL, which are licenses you use for your code. GPL stands for “General Public License” and the LGPL stands for “Lesser General Public License.” Licenses are by far the most confusing aspect of the whole Linux and Open Source phenomenon. In addition to the FSF group there is the Open Source Software group (OSS). Most people just looking into the subject think they are the same — but the OSS group led by Eric S. Raymond (ESR) is far more sane than the FSF group. Check out www.tuxedo.org/~esr/ and read ESR’s interesting book “The Cathedral and The Bazaar” for more on his views. You can read all about GPL and LGPL at www.gnu.org/licenses/licenses.html.

Now you may heard some of the fear, uncertainty and doubt about the GPL being spread by Microsoft. Let me say up front that I’m not a fan of the GPL, and we don’t use it at my company anymore. And the Linux community spends far too much time (in my opinion) talking about licenses and what is valid. The GPL does in fact have a viral nature about it. If you use GPL code in your application, then your application in turn must be made GPL. The GPL states that you must make the source available for others to modify and distribute at their whim. This is where a lot of confusion comes in.

See, the GPL doesn’t state that you must give source away. You can charge for any application, and you can charge to distribute the source. But the charge to distribute source must be a reasonable cost. My company sells one piece of GPL software we created; it has about 100 lines of other GPL code in it, which is why it has to use the GPL. And I get e-mails about once a week from people demanding their no-cost version of our application, because it used the GPL. A lot of this crowd are freeloaders, and they can be very frustrating.

There are licenses other than the GPL, and you can write your own if you want. We wrote a license that says the customer gets a copy of the source code, and they are free to work with it but not redistribute it. In my mind, this is the biggest problem for companies using the GPL; my license protects the customer and the company.

You can also use GPL code with a closed source application. We wrote a dynamic plug in system to do this (so we could mix our proprietary code with our GPL code), basically by dynamically loading the code and not linking to it. If your application will still run without any GPL code, then you can use this method. The LGPL allows you to link the code to a closed source application. If someone has made a library that you find useful, then you can use it if you like.

You should read up on the existing licenses if you plan on making use of them, and get your attorney’s opinion. The bottom line is that you don’t have to use the GPL. If you do, you can charge for your work, but you can’t stop other people from giving it away if they want, so use it with caution. RMS is just as frothy at the mouth about enforcing the GPL as Microsoft is about their licenses.

After 16 years of HP 3000 development, Shawn Gordon founded an application software company in the Linux market in 1999 called theKompany.com.