Re: The Ten-Line Weakness of the LGPL and the effects on GTK+/GLib

[Ben Gertzfield <che debian org>]

(Jakob, It would have been nice if your mailer obeyed the Reply-To:
header in the original mail. Ouch.)

>>>>> "Jakob" == Jakob 'sparky' Kaivo <jkaivo@ndn.net> writes:

    Jakob> this is not true. Reread the LGPL. Specifically, read
    Jakob> section 6 on what is required of a "work that uses the
    Jakob> Library". Notably, the work does *not* have to be licensed
    Jakob> under the GPL or less restrictive. Subsection 6b allows
    Jakob> that if the executable is dynamically linked, it fulfills
    Jakob> the requirements, since the user can replace the library
    Jakob> with a modified version.

Obviously this is not clear to even corporate lawyers, as they could
not make head nor tails of section 6. I'm just relaying the
information as IBM lawyers understand it; since the LGPL is written
extremely vaguely, nobody could actually understand it.

This is what section 6 says:

6. As an exception to the Sections above, you may also combine or link
a "work that uses the Library" with the Library to produce a work
containing portions of the Library, and distribute that work under
terms of your choice, provided that the terms permit modification of
the work for the customer's own use and reverse engineering for
debugging such modifications.

What if the terms do not permit 'modification of the work for the
customer's own use' or 'reverse engineering'? Then section 6 does not
apply.

    Jakob> Reread section 5. If the application can be compiled
    Jakob> without the library, it is not a derivative work. If your
    Jakob> code can compile with another C library than the GNU C
    Jakob> Library, it needn't be free software - but it does need to
    Jakob> dynamically link (rather than statically link) to the C
    Jakob> Library.

I was not talking about the GNU C library. I was talking about GLib.
There is no replacement for GLib at the moment, so programs that use
it can't compile without its headers, and thus are linked with the
library as per section 5:

'However, linking a "work that uses the Library" with the Library
creates an executable that is a derivative of the Library (because it
contains portions of the Library), rather than a "work that uses the
library". The executable is therefore covered by this License. Section
6 states terms for distribution of such executables.'

Since it is not specified here whether 'linking' means static or
dynamic linking, we must assume it means either, and so executables
dynamically linked against GLib are covered in Section 6, and thus
must be modifiable and reverse-engineerable. (is that a word?)

    Jakob> P.S. No flamewars on GPL vs. LGPL vs. BSD vs. AL vs. MPL
    Jakob> vs. whatever, definitions of free, how free various
    Jakob> licenses are, captialism vs.  communism, gun control, or
    Jakob> anything else, please. And of course, IMHO, IANAL, AFAIK,
    Jakob> HAND.

I wasn't intending to start a flamewar, just looking for clarification
on the LGPL so that it's *not* misunderstood as it and the GPL are
now.

Ben

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