[BRLTTY] Android: custom data files, BrlAPI and LineageOs

[Aura Kelloniemi]

Dave Mielke <Dave at mielke.cc> writes:
 > [quoted lines by Aura Kelloniemi on 2020/05/29 at 09:03 +0300]
 > >Where (which path, with which permissions, etc.) do I store custom text tables
 > >and keymaps? 

 > In the brltty/ folder at the top-level of the external storage device. Since
 > Android isolates an app (i.e. brltty) to its own user and group, others read
 > permission would be needed.

Ok, I will test that once I get so far. Does it work like the xdg-directory so
that I should not use any subdirectories under brltty/?

 > >And how does BrlAPI work on Android — specifically, how does it
 > >detect which application should be controlling the display?

 > It listens on 127.0.0.1:0, i.e. the main BrlAPI port on localhost.

Yes, I think this is good, but is there some sort of mechanism which BRLTTY
uses to detect which BrlAPI client application is focused (in the same way as
xbrlapi does it)? Because if not, it means that BrlAPI is not very useful on
Android.

 > >Also, has anybody run BRLTTY on LineageOs, and if so, what were the results?
 > What's that?

LineageOS is "a free and open-source operating system for various devices,
based on the Android mobile platform." https://www.lineageos.org/ In the
historic times it was called CyanogenMod. It allows to selectively install
Google Applications, which means that I do not need to run Google's spyware,
like the Google Play services.

 > >Then I have another question that is related to BrlAPI: would it be possible to
 > >run in Android a chroot or a container which runs a regular GNU userland with
 > >BRLTTY (possibly with the "GNU screen" screen driver and with the BrlAPI
 > >braille driver backed by the BrlAPI server running in Android userspace)?

 > You'd probably need to do your own Android build for that.

But why? Assuming that the container can connect to BrlAPI (which should not
be that difficult because it is listening on a TCP port), there should be a
way to run a local BRLTTY. This might require that I have rooted my phone (to
allow BRLTTY to access /dev/input, for instance), but I am going to do that
anyhow. I realize though that input device support might not be compiled to
the Android kernels, which would complicate this.

-- 
Aura