Re: question about HDF5 compound type macros...

Quincey Koziol <koziol@xxxxxxxxxxxxx> writes:

>> Ed:
>> 
>> I think you are true.
>
>     Indeed, yes.  However, it is appropriate becuase you want to get that
> machine's native settings for the struct in memory.  If you'd like to generate
> a "packed" compound type for storing the data on disk (which may not always be
> the best option, because it may require datatype conversions on more machines)
> you can use H5Tpack().  To generate a "native" compound datatype for a
> particular machine from a packed compound datatype, use H5Tget_native_type().
>
>     Quincey
>

Ah, now I think I am starting to understand why you have H5Tpack.

But to continue my line of questioning, in the example we've been
discussing, it would be possible to run identical code on two
machines, and get a different data file as a result?

I just re-read the H5Tpack documentation. Probably I need to pack all
my compound types to make sure that they come out the same way every
time.

But if I have a packed compound type, and I read it onto a array of
the struct that the compound type represents, then how does all the
data come out OK? Do you guys really read it member by member, and
adjust all the byte boundaries behind the scenes?

Thanks,

Ed


-- 
Ed Hartnett  -- ed@xxxxxxxxxxxxxxxx