----------- And then are licences that are file-level copylefts. The Mozilla Public License was the first of these. File-level copylefts say "If you modify the files of this program, the modified versions of those same files must be under this same licence". Now, that's not as strong as the GPL. The GPL says if you modify the program, you're whole modified program must be under the GPL. Those file-level copylefts, or we might call them weak copylefts, permit the additional of seperate files which are non-free. They don't really achieve the goal of copyleft, but because they made this requirement about the file, it's imposssible to relicense that file under the GPL. So the GPL will always be incompatible with those file-level copyleft licences.
Then there's the bizarre licence of TeX, which is incompatible with itself. [laughter] The licence of TeX says "You can't modify this file, but you can distribute it with a change file" and then when TeX is built, it's built by patching the standard TeX source code using the change file. So, in effect, you can distribute any modified version in that way, that's how I convinced myself in 1984 that that was a free software licence. But if you have two programs under the TeX licence, you can't merge them because each one says: anything that contains this can only be distributed as a changefile from this. So you have two things tugging at each other, each one insisting on being the base, the TeX licence is incompatible with itself, but it's a free software licence. ----------- The fellow should really go clinic... regards, alexander. _______________________________________________ gnu-misc-discuss mailing list gnu-misc-discuss@gnu.org http://lists.gnu.org/mailman/listinfo/gnu-misc-discuss