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[netCDF #YUI-809780]: CF proposed point obs convention

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  • Subject: [netCDF #YUI-809780]: CF proposed point obs convention
  • Date: Tue, 20 Jan 2009 09:33:02 -0700
Bruce,

That's a very good question.  The answer is that earlier versions of the
netCDF libraries have always been able to read data with arbitrary
characters in names.  The restriction has been on creating files with
names that contained "invalid" special characters.  The check for
characters used in names occurred when a program tried to define a new
variable, dimension, or attribute, and an error would be returned if the
characters in the names didn't follow the rules.  However, there has never
been any such check on reading data, so arbitrary characters could have
appeared in names created through a different implementation of the netCDF
APIs, or through early versions of netCDF software (before 2.4), which
allowed arbitrary names.

So in summary, the expansion to handle UTF-8 encoded Unicode characters and
special characters such as ":" and " " still conforms with Unidata's
commitment to backwards compatibility.  All old files are still readable
and writable by the new software, and programs that used to work will still
work when recompiled and relinked with the new libraries.  And beyond this,
files using new characters in names will still be readable and writable by
programs that used older versions of the libraries.  However, programs linked
to older library versions will not be able to create new data objects with
the new less-restrictive names.

--Russ



Russ Rew                                         UCAR Unidata Program
address@hidden                     http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: YUI-809780
Department: Support netCDF
Priority: Normal
Status: Closed