Re: How much work is a native Windows application? - Mailing list pgsql-hackers

"Marc G. Fournier" <scrappy@hub.org> writes:

> On Tue, 7 May 2002, Tom Lane wrote:
> 
> > It'd be worth trying to understand cygwin issues in detail before we
> > sign up to do and support a native Windows port.  I understand the
> > user-friendliness objection to cygwin (though one would think proper
> > packaging might largely hide cygwin from naive Windows users).  What I
> > don't understand is whether there are any serious performance lossages
> > from it, and if so whether we could work around them.
> 
> Actually, there are licensing issues involved ... we could never put
> a 'windows binary' up for anon-ftp, since to distribute it would
> require the cygwin.dll to be distributed, and to do that, there is a
> licensing cost ... of course, I guess we could require ppl to
> download cygwin seperately, install that, then install the binary
> over top of that ...

From the Cygwin FAQ:
       Is it free software?
       Yes. Parts are GNU software (gcc, gas, ld, etc...), parts are       covered by the standard X11 license, some of
itis public       domain, some of it was written by Cygnus and placed under the       GPL. None of it is shareware. You
don'thave to pay anyone to       use it but you should be sure to read the copyright section of       the FAQ more more
informationon how the GNU General Public       License may affect your use of these tools.
 

There is even a clause allowing you to link to the cygwin dll without
your software falling under the GPL if your software is released under
a license that complies with the Open Source Definition.
       *** NOTE ***
       In accordance with section 10 of the GPL, Red Hat permits       programs whose sources are distributed under a
licensethat       complies with the Open Source definition to be linked with       libcygwin.a without libcygwin.a
itselfcausing the resulting       program to be covered by the GNU GPL.
 
       This means that you can port an Open Source(tm) application to       cygwin, and distribute that executable as
ifit didn't include       a copy of libcygwin.a linked into it. Note that this does not       apply to the cygwin DLL
itself.If you distribute a (possibly       modified) version of the DLL you must adhere to the terms of       the GPL,
i.e.you must provide sources for the cygwin DLL.
 
       See http://www.opensource.org/osd.html for the precise Open       Source Definition referenced above.
       Red Hat sells a special Cygwin License for customers who are       unable to provide their application in open
sourcecode       form. For more information, please see:       http://www.redhat.com/software/tools/cygwin/, or call
  866-2REDHAT ext. 3007
 

In other words, you could even distribute a BSD licensed PostgreSQL
that that ran on Windows.  Not that such a loophole is particularly
useful.  GPL projects regularly include BSD code, this doesn't make
the BSD version GPLed.  The GPL might be viral in nature, but it's not
that viral.

Now, I can understand why the PostgreSQL mirrors might be a little bit
concerned about distributing GPLed software, because of the legal
ramifications, but they could leave the distribution of Cygwin up to
RedHat, and simply distribute a BSD-licensed PostgreSQL Windows
binary.

Jason