[dundee] questions about GPL

[Adam Sampson]

Tim Spencer <samurai.mit at gmail.com> writes:

> "According to the GPL our branding information must be displayed even
> if you modify the source code of the viewer."

(A quick search suggests that this is FlexPaper you're asking about, and
thus the GPLv3, although the GPLv2 has a similar clause.)

They're talking about clause 5d, which is one of the requirements when
distributing modified source code:

"d) If the work has interactive user interfaces, each must display
Appropriate Legal Notices; however, if the Program has interactive
interfaces that do not display Appropriate Legal Notices, your work need
not make them do so."

There's some clarification about this in the definitions at the start:

"An interactive user interface displays “Appropriate Legal Notices” to
the extent that it includes a convenient and prominently visible feature
that (1) displays an appropriate copyright notice, and (2) tells the
user that there is no warranty for the work (except to the extent that
warranties are provided), that licensees may convey the work under this
License, and how to view a copy of this License. If the interface
presents a list of user commands or options, such as a menu, a prominent
item in the list meets this criterion."

A typical implementation of this is the sort of thing interactive GNU
programs do:

> octave
GNU Octave, version 3.6.3
Copyright (C) 2012 John W. Eaton and others.
This is free software; see the source code for copying conditions.
There is ABSOLUTELY NO WARRANTY; not even for MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  For details, type `warranty'.

Thanks,

-- 
Adam Sampson <ats at offog.org>                         <http://offog.org/>