FW: NeXus licence

Ray Osborn ROsborn at anl.gov
Thu Oct 21 16:51:06 BST 1999

I received the following message today concerning licensing NAPI software.
It's an issue that I wanted to raise anyway with you, but I decided to wait
until we had got version 1.2.0 out the door.  If you don't know, the current
GNU Public License that we display on our FTP server does not allow anyone
to use the NeXus API in any software that is then sold for profit.  The
problem with this is that it prevents, say, IDL from ever supporting NeXus
directly (except through Mark's separate API).  A possibly more relevant
example would be the SPEC instrument operating system which is used at APS
and NSLS.  The developers could not use the NeXus API to store SPEC-produced
data as NeXus files.  In the long run, this could be a barrier to the use of

My personal view is that we should adopt what is now known as the Lesser GPL
which maintains the copyright freedom of use of the NeXus API, but allows it
to be used within commercial software if they so choose.  Does anyone else
have any opinions on this?  I must admit that I don't really know what the
legalities of changing the license are.  Perhaps we would have to release
another version (1.2.1) which specifically changes the terms of the license.

Dr Ray Osborn                Tel: +1 (630) 252-9011
Materials Science Division   Fax: +1 (630) 252-7777
Argonne National Laboratory  E-mail: ROsborn at anl.gov
Argonne, IL 60439-4845

> From: Dave Love <d.love at dl.ac.uk>
> Date: 21 Oct 1999 10:40:53 +0100
> To: ROsborn at anl.gov
> Subject: NeXus licence
> I'm considering trying to do support for X-ray area detectors in NeXus
> as an alternative to imgCIF, CBF, or whatever it is now.
> One aim is to get something adopted as a de facto standard for X-ray
> image data, particularly by the detector manufacturers, to avoid the
> current Babel of formats and lack of metadata.
> I think using napi would currently be a non-starter in that context
> because of the GPL licensing.  (I hack for GNU, so I don't ask
> lightly...  At least it's a sensible license, unlike the IUCr policy
> on CIF.)
> Would you consider changing that, perhaps with a special exception in
> the style of GNU Guile & al to permit the code to be linked with
> proprietary stuff?  The Lesser GPL would be another possibility,
> perhaps.
> Otherwise, do you have any particular advice for tackling image
> support?  I didn't get any answers from an enquiry of the mailing
> list.
> -- 
> Save Our Synchrotron  <URL: http://www.diamond.freewire.co.uk/>

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