Larry Brown wrote:
I just want to clarify this for myself. My impression was that the affects of GPL requiring software developed from the original GPL to also be free was only applicable to modifications of the program itself.
The GPL is a ridiculously outdated and vague license which has rarely been tested in any courts (if ever) and therefore there's no clearly established caselaw to base decision on.
'outdated'? 'vague'? GPL speaks of 'linking'. How is this to be defined? The GPL has language (linking, binary, compiler, kernel, etc) which is not something which even enters into the consideration of most developers who use scripting langauges (perl, php, python, etc). The GPL was written almost exclusively with C and similar languages in mind, although it's not explicitly stated anywhere. "derivative works" is not clearly defined. If I distribute a PHP script, is calling a 'wordwrap' function somehow 'linking' to the original PHP code? My program's functionality certainly depends on the wordwrap code functioning properly. Is it a 'work based on the Program'? The definition states that 'a "work based on the Program" means either the Program or any derivative work under copyright law: that is to say, a work containing the Program or a portion of it, either verbatim or with modifications and/or translated into another language.' Whose copyright law? The original developer's? The 2nd generation developer's? Translated into another language is damn vague, imo. If I take the original wordwrap function code - in C - and translate that to Python, have I translated it to another language? I realize that the PHP code isn't GPL - I'm not speaking specifically to PHP, but to the GPL 'definition' of things. It's a shame so many people just write stuff and put it out under GPL without coming close to understanding the implications of the license, or the ambiguities. At some point, there will be larger legal cases which will invalidate some of the principles which developers though the GPL meant, but didn't really understand.
So if php was
GPL and I modified the source and built my own customized version of php I
couldn't sell it but could only give it away,
You can sell GPL software. Often there's not much point because you have to grant the right of redistribution to others, so the first person you sold it to would be able to redistribute the source code (because they're entitled to recieve the original source code), thereby being able to undermine your sales efforts. In practice, many people probably wouldn't bother redistributing something, but it would only take one person to do so to have the impact. Also, just because something is GPL doesn't require the original developers to give it away to everyone by setting up FTP servers and all that other stuff. All you're required to do is provide to source to someone who requests it, and you only have to do that if they got it from you. Example: I have a large system which I GPL. I distribute a binary to customers who purchase it. My only obligation is to provide source code to the customer upon request. At that point, THEY can recreate a binary from my source and sell that, but they would also then have to fulfill requests for the source (which they may not want to do). *I* do not have to fulfill requests for the source to anyone except those to whom I distribute/sell a binary version. That's really it. but if I used php to develop
some other software that runs on php I could sell it without a problem.
Similar to creating software that runs on Linux, the software can be sold
but if I modify Linux itself and turn around and sell it, it would be
against the license.
Again, no, you can sell it, but you're obligated to provide the source to any purchser who requests it, and you can't then stop them from redistributing it. Any Linux kernel changes you made then 'sold' would either not sell at all, or would sell a couple copies then get rolled back in to the main tree of some distribution. Michael Kimsal PHP Training http://www.tapinternet.com/php 734-480-9961 -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
