[BRLTTY] Low-level BrlAPI questions

[Samuel Thibault]

Hello,

Good, we seem to converge :)

Dave Mielke, le dim. 09 mai 2021 13:03:40 -0400, a ecrit:
> [quoted lines by Samuel Thibault on 2021/05/09 at 13:01 +0200]
> >Really, the original intent was a straightforward:
> >
> >- if isArray = False, there is just one scalar value to return
> >- if isArray = True, there is possibly different values to return, and
> >  thus use whatever suits best the language (list, array, tuple) to
> >  convey the values, even if there is just one value.
> >- if count != 0 (only valid for isArray = True), the number of values
> >  being returned is always equal to that count.
> 
> Okay. The bit about count actually being meanless when isArray is false should probably be formally documented.

Yes.

> Or, we could change count to something more intuitively obvious like arraySize.

We can rename the field, yes. That breaks the API but not the ABI and I
don't think the API break will really pose problem in practice.

I'm also thinking that we could as well just squash the fields isArray
and hasSubparam into a flags field, since we also want to add can_read
and can_write, and possibly others in the future. We can make it a 16bit
field and make isarray bit 0 and hasubparam bit 8. That copes with ABI
compatibility on little-endian platforms, which is probably all that we
really care about concerning any potential use of brltty 6.3.

Samuel