Qlcplus: udev rules


#1

Hi everyone !
I try to use QLCplus on my Nixos 18.09 unstable but don’t know if i correctly add udev rules to use my dmxusb module. When I launch QLCplus it works but my dmxmodule isn’t recognize and when I launch QLCplus with sudo it work.
For the record I install the software with this line :

environment.systemPackages = with pkgs;  [ 
   qlcplus
]
services.udev.packages = [ pkgs.qlcplus ];

Is that correct ?

Someone known a bit more on what should I do ?
Maybe @globin you known a bit because you’re the maintainer :slight_smile:


#2

Hello,

By looking at files in the qlcplus package it appears that udev rules are stored in /lib/udev instead of /lib/udev/rules.d.

However the NixOS udev module is only looking in /lib/udev/rules.d nixos/modules/services/hardware/udev.nix#L49.

So maybe there should be a patch in the qlcplus package that move those files to the rules.d directory.

Here is the line that should be changed : pkgs/applications/misc/qlcplus/default.nix#L28

I made a PR here #51437


#3

Hi,
I test it and now there is udev rules. However my DMX module don’t response when I’m not root.


#4

Eureka !
So your fix @nyanloutre is a part of the solution. The PR #51437 solve the udev problem but I must add my user in the dialout group according to this documentation https://www.qlcplus.org/docs/html_en_EN/dmxusbplugin.html

Now it works :slight_smile:
Have a good day