mergeinputs

for some reason theres some issues using multiple keyboards simultaneously in linux, for some applications. this is a very small utility to merge/combine keyboards in linux into one merged input device.

usage

mergeinputs inputeventpaths
example to merge all keyboards: mergeinputs /dev/input/by-path/*-kbd

depending on your distro you might either need the input group or run mergeinputs as root.

but how does it work?

leveraging the uinput module, mergeinputs is able to sit before any userspace input drivers:

/dev/input/eventx /dev/input/eventy -> mergeinputs grabs all key events -> "merged input" device -> input drivers -> userspace applications

this means any application will only see one keyboard (merged inputs) pressing keys, eliminating any issues multiple devices might've caused.

install

make install

auto-start and reload on device change

To start the utility on every boot, a sample systemd unit is provided:

sudo cp mergeinputs.service /etc/systemd/system
sudo systemctl enable --now mergeinputs

If you want to restart mergeinputs on device changes to handle hotplugging of keyboards, use the mergeinputs-restart units:

sudo cp mergeinputs-restart.* /etc/systemd/system
sudo systemctl enable --now mergeinputs-restart.path