Add `STARTF_HOLOGRAPHIC` constant to `_winapi` module

[rruuaanng]

Feature or enhancement

Proposal:

This issue suggests adding new _winapi constants.

It is usually in the dwFlags member of lpStartupInfo parameter of CreateProcess and is used to run the application on a holographic device, such as Microsoft HoloLens or Windows Mixed Reality (Maybe there are others, but I haven't heard of them.)

e.g.

_winapi.CreateProcess(
                    python_exe, cmd,
                    None, None, False, 0, env, None,
                    STARTUPINFO(dwFlags=STARTF_HOLOGRAPHIC))

(It is only available in the when the system DDI is greater than win10 future.)

@zooba

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

[rruuaanng]

I'm not sure if this flag is worth adding, so I'll have to wait for Steve answer.

[zooba]

Considering Windows Mixed Reality has been deprecated and removed (much to my dismay, as my VR headset no longer works 😢), I don't think there's any value in this flag?

It should be easy enough for people to grab the value of it and pass an int. That is necessary for older Python versions anyway, and I don't think we want to encourage use of something that is gone.

[rruuaanng]

So should I close this issue? Will this flag be deprecated in the future? I haven't received any news on this. Maybe there will be new VR devices?

[zooba]

Yeah, I really don't know what the future holds here on what's best to do about it.

In general though, the _winapi module is only to support the standard library, so if we don't have a use for it in the stdlib, we wouldn't add it. I don't believe we have a need for this constant, so let's leave it for now.