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I keep translating the Debian wiki page about accessibility into German. This helps me following the latest accessibility developments within the project. This way, I recently learned about accessible virtualization, which I am going to introduce here.

I already knew about the -curses option for QEMU/KVM to start a guest on the console, which gives basic accessibility through the host's command line screen reader. However, qemu supports sound card pass through and the simulation of a braille device, which both together enable the full usage of the guest system.

To enable braille in the guest, qemu simulates a braille display of a specific vendor. All requests from the guest system to this virtual device are then passed onto BRLTTY, which has to run on the host system. BRLTTY is a command line screen reader and it also features a braille API (BRLAPI), so that other applications can control the braille device. Qemu uses this facility to pass-through output from the screen reader in the guest system to the physical device on the host machine.

The discussed options are:

-soundhw all -usbdevice braille

That's it, assuming you have BRLTTY set up and you know how to use qemu.\ Please have a look at the Debian Wiki page about accessibility for more details.



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