Hi Pierre!

> I haven't looked closely at your patch, but here is the rule for
> copy-build-system if I'm not mistaken: the files matching #:include
> preserve the path relative to the first argument.
> 
> For instance with this rule
> 
> ("/source/aaa/" "/target/bbb/" #:include ("foo"))
> 
> the file
> 
>      /source/aaa/parent/foo
> 
> is copied to
> 
>      /target/bbb/parent/foo
> 
> (I haven't tested.)
> 
> Does that help?

With the same example, I was looking for a way where foo gets copied to 
as /target/bbb/foo.

Regards,
RG.