[BRLTTY] Footsteps towards better accessibility in Linux

[Christian Schoepplein]

Hi Dave,

On Thu, Apr 03, 2025 at 12:01:51PM -0400, Dave Mielke wrote:
>[quoted lines by Halim Sahin on 2025/04/03 at 16:49 +0200]
>
>>Does  the new code also handle pc keyboard input in Xorg / wayland to
>>control brltty functions?
>
>I think it should. Perhaps you can experiment with it. To enable the 
>keyboard in the GUI, use the -g (lowercase) option. There's also a -G 
>(uppercase) option which lets you specify a different keyboard table for 
>the GUI - if you don't then the main keyboard table will be used for both.

I gave this a try and started brltty this way with my normal user, not 
root, in a Mate environment. In /etc/brltty.conf I set the keyboard-table 
parameter to laptop to make sure that the laptop keymap is used:

brltty -b ba -s sd -x a2 -N -g

This changed nothing. I am not able to use my normal laptop keyboard to 
control brltty. It is the same behaviour like running brltty without the -g 
and -G parameter.

If I change to a normal console e.g. with Ctrl+Alt+F2 and login with my 
normal user, not root, it seems to work. There I can e.g. change the 
displayed line using Capslock+ArrowUp or Capslock+ArrowDown or start the 
learning mode with Capslock+Shift+F1.

Now I wonder if this is a permission problem because for Mate brltty is 
running without root user privileges? If I start brltty I see the following 
output:

BRLTTY 6.7 rev BRLTTY-6.7 [https://brltty.app/]
brltty: can't isolate namespaces
brltty: executing as the invoking user: cs
brltty: can't set supplementary groups
brltty: group not joined: 0(root)
brltty: group not joined: 5(tty)
brltty: required capability not granted: cap_sys_admin (for injecting input 
characters typed on a braille device)
brltty: required capability not granted: cap_sys_tty_config (for playing 
alert tunes via the built-in PC speaker)
brltty: required capability not granted: cap_mknod (for creating needed but 
missing special device files)

I wonder how to start brltty with sufficient permissions in a grafical 
environment where working as the root user is not possible and should be 
avoided for security reasons anyway.

BTW.: Thank you very much working on brltty and also implementing new 
features! I use brltty nearly every day and like it a lot. Without brltty I 
would not be able to work in my job as a devops engineer, so for me brltty 
is  one of the key software I need for my daily work.

Cheers,

  Schoepp