[Ffmpeg-devel] About LGPL for commercial product

[Michel Bardiaux]

Luca Abeni wrote:
> Hi Luca,
[snip]
> This is probably unrelated to the original question, but I always
> wondered why LGPL is not ok with static linking...
> 
> Out of curiosity: if I statically linked my program to libavcodec, and
> then I distributed
> 	1) the binary of my program
> 	2) the source of libavcodec
> 	3) the .o needed for obtaining my program (when linked with libavcodec)
> 
> would I violate the LGPL? (would I need to distribute a makefile too?)
> 

<IANAL mode on>You have to distribute whatever is needed to perform the 
static linking and is not 'normally expected' on any target system. That 
means you dont have to distribute gcc, and some very basic script or 
even howto like

gcc -o myprogram myprogram.o libavutil.a ...

is good. The common insistence on dynamic linking comes from the 
assumption that shared libraries maintain compatible ABIs, so if the end 
users want to use a new-and-improved-ffmpeg with a closed-source 
program, all they have to do is upgrade their libavutil.so etc...

HaND,
-- 
Michel Bardiaux
R&D Director
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