When to evaluate dual licenses (was: license categories, was: I'm not supposed to use the ECL v2?)

[Chuck Swiger]

On Dec 3, 2007, at 10:13 AM, Chris Travers wrote:
> However, suppose I have a work under a permissive license which  
> links to GNU Readline.  That is permitted too.  But anyone who wants  
> to use GNU Readline in their proprietary spinoff's cannot.  For  
> example, PostgreSQL links to both GNU Readline and OpenSSL, and  
> nobody has really complained.


If Postgres also works without GNU readline, or if it also works using  
the BSD-licensed version of libreadline, then it seems clear enough  
that Postgres by itself is not a derivative work of GNU readline.   
However, a precompiled binary which statically links in GNU readline  
clearly would be.

The same would apply to a proprietary closed-source program-- if it  
ships as a binary which statically links in GNU readline, than they  
need to honor the GPL and release their sources.  The interesting case  
is what happens if a proprietary binary works fine as is, but is  
willing to dynamically load libreadline if available.  :-)

-- 
-Chuck