On Mon, Apr 24, 2017 at 7:07 PM, Nathaniel Smith <njs@pobox.com> wrote:

> That said, AFAICT what people actually want in most use cases is support for arrays that can hold variable-length strings, and the only place where the current approach is *optimal* is when we need mmap compatibility with legacy formats that use fixed-width-nul-padded fields (at which point it's super convenient). It's not even possible to *represent* all Python strings or bytestrings in current numpy unicode or string arrays (Python strings/bytestrings can have trailing nuls). So if we're talking about tweaks to the current system it probably makes sense to focus on this use case specifically.
>
> From context I'm assuming FITS files use fixed-width-nul-padding for strings? Is that right? I know HDF5 doesn't.

Yes, HDF5 does. Or at least, it is supported in addition to the variable-length ones.