H5Part development and discussion

[John Biddiscombe <biddisco AT cscs.ch>]

> With this definition _h5get_errno() expands to something different 
> than you set with _h5set_errno(a). "_errno" is an internal H5Part 
> error number but "errno" is the system error number! It might be the 
> best to rename "_errno" to something like "_h5part_errno" ...
>
> With above definition the patch 
>
> -       return _errno;
> +       return _h5get_errno();
>
> is wrong!
>   
Aha. I probably didn't see an underscore and missed the distinction. 
Confusingly on win32 the system defines
#define errno   (*_errno())

Which is nice!

Is it your intention to use only the h5part _errno or the system errno - 
if you are not using the system errno at all, then the problem is much 
simpler and we simply call the variable _h5errno and the need for win32 
specific #defines goes away.

I was just getting my next patch ready too. Now I'll have to back 
everything up and start again.

JB