> Is the author still adding the "cite me or pay 10000€" notice to the output? And calling that GPL?
Where you get the "or pay 10000€" part from? As far as I remember, the software, unless told otherwise, asks authors of scientific papers to cite GNU parallels if they used it when writing their papers. And it doesn't force it, it's not part of the license, but asks you to do so as it's academic tradition to use citations.
You could just ignore the citation and not break the license, no one would think less of you for doing so.
If you use --will-cite in scripts to be run by others you are
making it harder for others to see the citation notice. The
development of GNU parallel is indirectly financed through
citations, so if your users do not know they should cite then you
are making it harder to finance development. However, if you pay
10000 EUR, you have done your part to finance future development
and should feel free to use --will-cite in scripts.
If you do not want to help financing future development by letting
other users see the citation notice or by paying, then please
consider using another tool instead of GNU parallel. You can find
some of the alternatives in man parallel_alternatives.
FWIW some distros remove the nagging message (e.g. mine - openSUSE - has it removed and the patch seems to come from Debian so i'd guess Debian and its derivatives also remove it).
Again, it's not part of the license nor are you forced to select between "cite GNU parallels or pay 10000 EUR". You're free to use it however you want since the software is GPL, including ignoring any of the output from using the tool if you so chose to.
> including ignoring any of the output from using the tool if you so chose to.
the user isn't merely ignoring the output though, they are actively interacting with the program in a way that the program is presenting as accepting of the agreement being presented to the user.
the agreement is plainly presented in a way that implies that it's an obligation, like any other clickwrap agreement. and everyone except ole and stallman seems to agree that it's self-evidently apparent that it's a clickwrap agreement restricting the freedoms of the user.
"free software that only prints a message and exits unless you agree to a clickwrap with further licensing terms" is not a road that FSF should go down. And it's only because of the GPL severability clause that it's not a crisis, everyone knows it's a farce, except for a bunch of the users, who are affirmatively taking action to indicate consent with an additional licensing agreement.
it's not facially clear that in most jurisdictions that the clickwrap agreement is null and void merely because the software is free. you can end up paying for lots of free stuff in life if you're not careful. you agreed to the agreement, it's on you.
you are of course free to remove the prompt and use the software yourself, and ole rants and raves about that on his website. but, agreeing to the license is a separate thing from the GPL license, most likely. just like paying for credit monitoring is different from getting your free credit reports or freezes - they'll try and railroad you into paying, definitely! and just because it's supposed to be free, doesn't mean you're not getting charged if you agree to it!
If you read the FAQ they have regarding the citation notice for GNU Parallel, it's made clear that it is not part of the license in any way and only applies to projects that are part of/the basis for academic papers. If it does apply to your project and you don't cite, at absolute worst you could get in trouble with your university or the academic community but even then it's almost certainly going to be mild at worst.
But importantly you can use the software however you want that is compatible with GPLv3. That includes ignoring or removing the citation notice without paying a cent. However just because it's legal doesn't mean it won't come with the potential for social consequences.
== Is the citation notice compatible with GPLv3? ==
Yes. The wording has been cleared by Richard M. Stallman to be compatible with GPLv3. This is because the citation notice is not part of the license, but part of academic tradition.
Therefore the notice is not adding a term that would require citation as mentioned on:
https://www.gnu.org/licenses/gpl-faq.en.html#RequireCitation
The link only addresses the license and copyright law. It does not address academic tradition, and the citation notice only refers to academic tradition.
[...]
and from the GPL faq itself (which said citation FAQ references):
Does the GPL allow me to add terms that would require citation or acknowledgment in research papers which use the GPL-covered software or its output? (#RequireCitation)
No, this is not permitted under the terms of the GPL. While we recognize that proper citation is an important part of academic publications, citation cannot be added as an additional requirement to the GPL. Requiring citation in research papers which made use of GPLed software goes beyond what would be an acceptable additional requirement under section 7(b) of GPLv3, and therefore would be considered an additional restriction under Section 7 of the GPL. And copyright law does not allow you to place such a requirement on the output of software, regardless of whether it is licensed under the terms of the GPL or some other license.
TLDR: The citation notice is a "cite it in academic works or pay me" agreement that is as legally binding as a pinky promise. You can break it without concern but some people may look negatively on that and it may come with social consequences.
Not really. It's more like if you use it for free please cite but if you're so averse to citing that you'd rather send a gazillion money then feel welcome to do so, at least that is the way I read it.
Where you get the "or pay 10000€" part from? As far as I remember, the software, unless told otherwise, asks authors of scientific papers to cite GNU parallels if they used it when writing their papers. And it doesn't force it, it's not part of the license, but asks you to do so as it's academic tradition to use citations.
You could just ignore the citation and not break the license, no one would think less of you for doing so.