[BRLTTY] linux screen driver and commands
Mario Lang
mlang at delysid.org
Fri Mar 10 04:04:40 EST 2006
Samuel Thibault <samuel.thibault at ens-lyon.org> writes:
> While working on Linux kernel facilities for speech-based screen
> readers, I found an interesting possibility for driving brltty's speech
> with the PC keyboard, without having to patch the Linux kernel:
>
> - open /dev/input/event0 (provided by the evdev module)
> - call ioctl(fd, EVIOCGRAB, 1) on it: key presses stop being sent to the
> linux virtual console: instead,
> - read(fd,buf,sizeof(struct input_event)) gets the key press event.
>
> This hence permits to grab key presses, which can then be used for
> driving speech reading etc., while the usual key presses can be
> simulated back via the uinput facility that we already implemented (the
> simulated device will appear as another /dev/input/event1 evdev file).
Yes, I already suggested this plan to Dave in a private mail
about a year ago or so. It was especially interesting to some, since
there are braille displays out there which do not have any display-local
keys. AFAICS, the only reason why it is not there yet is
because no one implemented it. ITs truly simple though, at least
the key-forwarding part.
There is a problem though: How do you figure out which
keyboard to grab? I use a USB keyboard at times, and my PS/2
keyboard is still connected, so I definitely have two
system-console keyboards. Actually, three, since I
use the Braille Star built-in PS/2 port, but that doesnt really
count.
> I will probably not work on this, but this should be enough material for
> somebody to do it :)
Ahhh, dejavu ! :)
--
CYa,
Mario
More information about the BRLTTY
mailing list