Re: [h5md-user] Strings again / parallel issue

[Pierre de Buyl]

On Fri, Feb 07, 2014 at 10:05:48AM +0100, Felix Höfling wrote:
> >Actually, I have the feeling that variable-length "whatever" in
> >HDF5 should be
> >used only when there is no choice (i.e. data for which you have
> >significant
> >variations in the size of each element).
> >
> >This comes from:
> >1. the fact that the vl-string attribute routine is missing in
> >Fortran 90.
> >2. h5py's documentation
> >http://docs.h5py.org/en/latest/strings.html#compatibility
> >3. VL is reported not to work in parallel settings in the HDF5 FAQ
> >
> >So making the choice may actually prevent us from shooting
> >ourselves in the foot
> >:-)
> >
> 
> I agree with you. The parallel context is an important reality for H5MD
> applications. Not being able to read some data from the file in such a
> situation would be a no-go. I had assumed that any valid HDF5 file can
> always be read.
> 
> So let's stick to truly Atomic types only, i.e. fixed-length strings
> everywhere. The HDF5 library is really confusing here by pretending that
> VL strings are atomic.

It is just annoying that I catched these parallel-related issues so late but
I think we have made the most compatible choice.

Anyway, I'm happy to have this string issue sorted!

P