obtaining offset length pairs from dataspace id

Hello,

I am writing an external HDF5 VOL plugin. I have implemented the base
mappings between main data model objects (container, groups and datasets)
and corresponding storage representations.

At this point I have to implement the dataset read/write functions and thus
I need to reconstruct the offset length pairs starting from the dataspace
id describing the data layout inside the file.

Apparently I cannot use the H5S_select_get_seq_list() function since this
is only available to internal plugins while I am writing an external plugin.

In the public API there are a couple of functions to extract this type of
information from the dataspace, e.g. H5Sget_select_hyper_blocklist(), but
they do not return directly the offset and length pairs like the internal
function previously mentioned does.

Unfortunately my experience with HDF5 dataspaces is not that deep and I am
wondering what is the best way of extracting the information I need from
the dataspace id.

Thanks,

···

--
Giuseppe Congiu *·* Research Engineer II
Seagate Technology, LLC
office: +44 (0)23 9249 6082 *·* mobile:

Giuseppe,

Thanks for bringing this to our attention. This is definitely something we should consider adding before the HDF5 VOL is included in a release. For now, you need to either do the calculations on your own or add the public API function to the HDF5 library. Sorry for the delay in responding.

-Neil

···

________________________________________
From: Hdf-forum <hdf-forum-bounces@lists.hdfgroup.org> on behalf of Giuseppe Congiu <giuseppe.congiu@seagate.com>
Sent: Monday, October 10, 2016 9:15:23 AM
To: hdf-forum@lists.hdfgroup.org
Subject: [Hdf-forum] obtaining offset length pairs from dataspace id

Hello,

I am writing an external HDF5 VOL plugin. I have implemented the base mappings between main data model objects (container, groups and datasets) and corresponding storage representations.

At this point I have to implement the dataset read/write functions and thus I need to reconstruct the offset length pairs starting from the dataspace id describing the data layout inside the file.

Apparently I cannot use the H5S_select_get_seq_list() function since this is only available to internal plugins while I am writing an external plugin.

In the public API there are a couple of functions to extract this type of information from the dataspace, e.g. H5Sget_select_hyper_blocklist(), but they do not return directly the offset and length pairs like the internal function previously mentioned does.

Unfortunately my experience with HDF5 dataspaces is not that deep and I am wondering what is the best way of extracting the information I need from the dataspace id.

Thanks,

--
Giuseppe Congiu · Research Engineer II
Seagate Technology, LLC
office: +44 (0)23 9249 6082 · mobile:
www.seagate.com<http://www.seagate.com>