[ILUG] GPL and LGPL

[Michael Conry]

On 4/22/05, Robert Kiely <robert.kiely at gmail.com> wrote:
> But what about the libraries that are used... for example is it
> possible to use a proprietary libc with linux or does the GPL prevent
> this. As far as I understand the way that proprietary program run on
> linux is because all the libraries are LGPL. So I suppose what I'm
> really asking is about libraries that run on a kernel or interface
> directly with it... how does GPL software allow LGPL software to link
> with it ?
As I understand it, if the library is licensed under the full GPL,
then applications linked with it must also be GPL.  If it's licensed
under the LGPL, then that requirement is not imposed (although if you
extend the library, then the extended/modified library must also be
LGPL (maybe the changes could acceptably be GPL licensed also?)).

http://www.gnu.org/philosophy/why-not-lgpl.html
The above link gives info on when Richard Stallman would recommend to
use GPL/LGPL (in that case Library-GPL, superseded now by the
Lesser-GPL).  Basically, the suggested criteria is that if the library
is revolutionary, one-of-a-kind, then keep it GPL to help other GPL
developers at the expense of proprietary work.  If there are many
proprietary (or BSD-licensed) alternatives, then LGPL will be better
in order to get the maximum user-base.

the GNU standard C library is LGPL, so you can link against it without
problems. You can also run proprietary software on a Linux system
without restriction.

(none of the above is legal advice!)
Michael