Should H5Pset_obj_track_times() survive file re-open?

Hi All,

I am using H5Pset_obj_track_times to turn off setting ctime in output
files. This is great, it makes it easy to detect changes in output
using a simple file hash!

I noticed that H5Pget_obj_track_times() gives me the expected value in
a newly created dataset (false if set to false by
H5Pset_obj_track_times(), true if unset or set to true by
H5Pset_obj_track_times()). However, the flag does not seem to be
recoverable after file close / re-open. If I close the file, re-open,
get the dataset creation property list with H5Dget_create_plist(),
then call H5Pget_obj_track_times() again, it always gives me "true".
Is this expected?

IIUC, this does not matter much in HDF as currently implemented
because only ctime is ever set, so it doesn't matter if the dataset
remembers that it is not supposed to track times (because the only
time fields are modified is at creation anyway). Am I thinking about
this right?

Happy to provide a MWE if helpful.

Thanks!

Alex

Hi Alex,
  This seems like a bug. Please let the helpdesk (help@hdfgroup.org <mailto:help@hdfgroup.org>) know about it.

    Quincey

···

On Aug 22, 2017, at 9:04 PM, Alex Cobb <alex.cobb@smart.mit.edu> wrote:

Hi All,

I am using H5Pset_obj_track_times to turn off setting ctime in output
files. This is great, it makes it easy to detect changes in output
using a simple file hash!

I noticed that H5Pget_obj_track_times() gives me the expected value in
a newly created dataset (false if set to false by
H5Pset_obj_track_times(), true if unset or set to true by
H5Pset_obj_track_times()). However, the flag does not seem to be
recoverable after file close / re-open. If I close the file, re-open,
get the dataset creation property list with H5Dget_create_plist(),
then call H5Pget_obj_track_times() again, it always gives me "true".
Is this expected?

IIUC, this does not matter much in HDF as currently implemented
because only ctime is ever set, so it doesn't matter if the dataset
remembers that it is not supposed to track times (because the only
time fields are modified is at creation anyway). Am I thinking about
this right?

Happy to provide a MWE if helpful.

Thanks!

Alex

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@lists.hdfgroup.org
http://lists.hdfgroup.org/mailman/listinfo/hdf-forum_lists.hdfgroup.org
Twitter: https://twitter.com/hdf5

Thank you, Quincey and Alex! I entered bug HDFFV-10281 for this issue.
An example program to reproduce this with would be very helpful!

-Barbara
help@hdfgroup.org<mailto:help@hdfgroup.org>

···

From: Hdf-forum [mailto:hdf-forum-bounces@lists.hdfgroup.org] On Behalf Of Quincey Koziol
Sent: Wednesday, August 23, 2017 10:06 AM
To: HDF Users Discussion List
Subject: Re: [Hdf-forum] Should H5Pset_obj_track_times() survive file re-open?

Hi Alex,
            This seems like a bug. Please let the helpdesk (help@hdfgroup.org<mailto:help@hdfgroup.org>) know about it.

                        Quincey

On Aug 22, 2017, at 9:04 PM, Alex Cobb <alex.cobb@smart.mit.edu<mailto:alex.cobb@smart.mit.edu>> wrote:

Hi All,

I am using H5Pset_obj_track_times to turn off setting ctime in output
files. This is great, it makes it easy to detect changes in output
using a simple file hash!

I noticed that H5Pget_obj_track_times() gives me the expected value in
a newly created dataset (false if set to false by
H5Pset_obj_track_times(), true if unset or set to true by
H5Pset_obj_track_times()). However, the flag does not seem to be
recoverable after file close / re-open. If I close the file, re-open,
get the dataset creation property list with H5Dget_create_plist(),
then call H5Pget_obj_track_times() again, it always gives me "true".
Is this expected?

IIUC, this does not matter much in HDF as currently implemented
because only ctime is ever set, so it doesn't matter if the dataset
remembers that it is not supposed to track times (because the only
time fields are modified is at creation anyway). Am I thinking about
this right?

Happy to provide a MWE if helpful.

Thanks!

Alex

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@lists.hdfgroup.org<mailto:Hdf-forum@lists.hdfgroup.org>
http://lists.hdfgroup.org/mailman/listinfo/hdf-forum_lists.hdfgroup.org
Twitter: https://twitter.com/hdf5

Thanks Quincey, will do.

Alex

···

On 23 Aug 2017 11:07 pm, "Quincey Koziol" <koziol@lbl.gov> wrote:

Hi Alex,
This seems like a bug. Please let the helpdesk (help@hdfgroup.org) know
about it.

Quincey

On Aug 22, 2017, at 9:04 PM, Alex Cobb <alex.cobb@smart.mit.edu> wrote:

Hi All,

I am using H5Pset_obj_track_times to turn off setting ctime in output
files. This is great, it makes it easy to detect changes in output
using a simple file hash!

I noticed that H5Pget_obj_track_times() gives me the expected value in
a newly created dataset (false if set to false by
H5Pset_obj_track_times(), true if unset or set to true by
H5Pset_obj_track_times()). However, the flag does not seem to be
recoverable after file close / re-open. If I close the file, re-open,
get the dataset creation property list with H5Dget_create_plist(),
then call H5Pget_obj_track_times() again, it always gives me "true".
Is this expected?

IIUC, this does not matter much in HDF as currently implemented
because only ctime is ever set, so it doesn't matter if the dataset
remembers that it is not supposed to track times (because the only
time fields are modified is at creation anyway). Am I thinking about
this right?

Happy to provide a MWE if helpful.

Thanks!

Alex

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@lists.hdfgroup.org
http://lists.hdfgroup.org/mailman/listinfo/hdf-forum_lists.hdfgroup.org
Twitter: https://twitter.com/hdf5

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@lists.hdfgroup.org
http://lists.hdfgroup.org/mailman/listinfo/hdf-forum_lists.hdfgroup.org
Twitter: https://twitter.com/hdf5

Thank you, Barbara! I will follow up to the help desk with a minimal
working example.

Alex

···

On 23 Aug 2017 11:43 pm, "Barbara Jones" <bljones@hdfgroup.org> wrote:

Thank you, Quincey and Alex! I entered bug HDFFV-10281 for this issue.

An example program to reproduce this with would be very helpful!

-Barbara

help@hdfgroup.org

*From:* Hdf-forum [mailto:hdf-forum-bounces@lists.hdfgroup.org] *On Behalf
Of *Quincey Koziol
*Sent:* Wednesday, August 23, 2017 10:06 AM
*To:* HDF Users Discussion List
*Subject:* Re: [Hdf-forum] Should H5Pset_obj_track_times() survive file
re-open?

Hi Alex,

            This seems like a bug. Please let the helpdesk (
help@hdfgroup.org) know about it.

                        Quincey

On Aug 22, 2017, at 9:04 PM, Alex Cobb <alex.cobb@smart.mit.edu> wrote:

Hi All,

I am using H5Pset_obj_track_times to turn off setting ctime in output
files. This is great, it makes it easy to detect changes in output
using a simple file hash!

I noticed that H5Pget_obj_track_times() gives me the expected value in
a newly created dataset (false if set to false by
H5Pset_obj_track_times(), true if unset or set to true by
H5Pset_obj_track_times()). However, the flag does not seem to be
recoverable after file close / re-open. If I close the file, re-open,
get the dataset creation property list with H5Dget_create_plist(),
then call H5Pget_obj_track_times() again, it always gives me "true".
Is this expected?

IIUC, this does not matter much in HDF as currently implemented
because only ctime is ever set, so it doesn't matter if the dataset
remembers that it is not supposed to track times (because the only
time fields are modified is at creation anyway). Am I thinking about
this right?

Happy to provide a MWE if helpful.

Thanks!

Alex

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@lists.hdfgroup.org
http://lists.hdfgroup.org/mailman/listinfo/hdf-forum_lists.hdfgroup.org
Twitter: https://twitter.com/hdf5

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@lists.hdfgroup.org
http://lists.hdfgroup.org/mailman/listinfo/hdf-forum_lists.hdfgroup.org
Twitter: https://twitter.com/hdf5