[BRLTTY] Associate an action to the bell on the console?

[Aura Kelloniemi]

Hi,

On 2025-12-07 at 14:16 +0100, Sébastien Hinderer <sebastien.hinderer at ens-lyon.org> wrote:
 > Is there a way to configure how the bell is emitted by Linux's virtual
 > console, currently? I mean, beyond audible and visual bell, is there a
 > possibility to configure a program that should be run to emit the bell?

No, there isn't.

 > I assume not, so likely the real question is would it be possible to get
 > that and what kind of work would that involve?

A quick anwer would be no, this won't happen. This would be a BIG security
issue. The spawned process should probably have the same permissions as the
process, which originally causes bell to be signaled, but the kernel cannot
know who originally sent the bell character (because the program which prints
the bell might not be the same process which decided to write bell to its
output stream).

This could be mitigated by always running the bell-handler process with static
permissions, but this probably would reduce its usefulness.

Another reason against this might be that forking a process is expensive.
Kernel spawns new user processes sparingly, probably for good reasons.

-- 
Aura