Re: something startling I just noticed...

Hi Ed,

> If you HDF5 guys implement the indexing and shared dimensions, we will
> be able to create and read a HDF5 file using the netcdf-4 interface
> with no special attributes that need to be understood.
    Yes, that's my goal. :-)

> If that's true, can we use the netcdf-4 interface to read *other* HDF5
> files, even though they weren't created with netcdf-4? The only
> impediments are the indexing of datasets, attributes, and shared
> dimensions in creation order.
> If all HDF5 files had this indexing, We might very easily be able to
> operate on *any* HDF5 file. What do you think Quincey?
    Yup.  *happiness*

> And, if it comes right down to it, why not fake it?  Quincey, if I
> iterate through the list of datasets, I'll get them in alphabetical
> order? Is that correct?

> As long as I provide a consistent numbering scheme, it seems like
> most software (eg. grads) that uses netcdf might well be able to read
> HDF5 files that were created before this project even started, though
> they obviously wouldn't have shared or named dimensions.
    Yes, that would certainly work.  The only issue is the names that the users
assign to the datasets would probably break this scheme.
    My current idea is to add a "creation time" piece of metadata to each
object as it is created in the file, and then the H5Giterate() call (or
something resembling it) could choose whether to use creation times or the
object names (or last modification times, etc.) as the method of indexing the
objects to iterate over.  Fairly simple and straightfoward, I think...