[Project-managers] editing external codes

[Ted Ralphs]

This is all shades of gray and little of it has been tested in court, so 
it's difficult to say. I think this could probably be considered "fair 
use" if it does not involve a substantial portion of the application's 
source code:

http://www.bitlaw.com/copyright/fair_use.html

However, the safest route is always to provide a patch and distribute 
that, rather than the source code itself.

Cheers,

Ted

Matthew Galati wrote:
> FYI - cliquer is code for finding maximal cliques (its listed in COIN 
> resources):
>   http://www.coin-or.org/resources.html
>   http://users.tkk.fi/~pat/cliquer.html
> 
> I'll write the author and ask if they want the fix. That would be easier.
> 
> Here's a related question that brings into question the same issues of 
> licenses and distribution.
> 
> My project is written in C++. Cliquer is C. I build cliquer with gcc and 
> the Makefile they provide - and it works fine. I call cliquer via extern 
> "C"...  However, cliquer, like alot of "old" C code I've seen has some 
> bad habits that don't play nicely with C++ compilers (like g++). For 
> example, cliquer's prototypes include the name "new" and "set" as a 
> variable name. A C++ compiler won't have that. The way I get around this 
> kind of thing is to write an "interface" header where I wrote my own 
> prototypes for whatever I actually call from my code, then extern "C" 
> {#include "cliquerInterface.h"}. Then, of course, I distribute my 
> cliquerInterface.h. I presume this is all ok wrt to licenses. But, it 
> gets a little sticky when I start using macro defines that come from the 
> original cliquer.h. Since I am not including cliquer.h, but rather 
> cliquerInterface.h, I have to copy the macros over too - which for some 
> codes is a bunch of stuff. Is that now a license issue? I am taking bits 
> of the GPL code and distributing it with my code in my interface header.
> 
> This license stuff all seems very messy to me. Why can't I add GPL code 
> in my COIN code and just distribute my stuff GPL and CPL and 
> 'whoever-wants -it-feel-free-to-use-it- PL'.
> 
> Matt
> 
> 
>> Hi Matt,
>>
>> I don't know what Cliquer is, but the ideal case would be that you get 
>> the Cliquer developers to include your changes in a new version.  They 
>> would probably be grateful to get fixes that make it work on Windows...?
>>
>> Otherwise, you could include patch files in your distribution and tell 
>> users that want to use Cliquer on Cygwin how they have to apply the 
>> patches to Cliquer code that they download separately.
>>
>> Andreas
>>
>> On Fri, 6 Apr 2007, Matthew Galati wrote:
>>
>>> In one of the examples in my project DECOMP, I use a GPL licensed 
>>> code (Cliquer). In my INSTALL, I provide the user the option to 
>>> download and link with it or not (and give them www). It works fine 
>>> with unix flavors, but Cliquer was never written to run on Windows. I 
>>> can fix the Cliquer code to compile in Windows with a few ifdef's.
>>>
>>> But, now how does this work? I know I am not suppose to distribute 
>>> Cliquer via svn. If so, I could just provide my "adjusted" Cliquer.
>>>
>>> I guess, this is a general question -- how do I distribute 
>>> derivatives of other external codes to be used with my COIN project?
>>>
>>> Thanks,
>>> Matt 
> _______________________________________________
> Project-managers mailing list
> Project-managers at list.coin-or.org
> http://list.coin-or.org/mailman/listinfo/project-managers


-- 
Dr. Ted Ralphs
Associate Professor
Industrial and Systems Engineering
Lehigh University
(610)758-4784
tkralphs at lehigh.edu
www.lehigh.edu/~tkr2