来自 root 用户的 Wayland 检测

Question

I have a script that must be launched as root. I need to detect the graphics system and identify it (windows X system, Wayland).

I tried using some environment vars like ${XDG_SESSION_TYPE} or ${WAYLAND_DISPLAY} which are revealing if you are using x11 or wayland, or if you are in a headless system... but, the problem is that the vars are not working from root user. As you know, the graphics environment is usually launched by a normal user and as I said at the beginning of the question, for reasons that I'm not going to explain here, the script needs to be launched as root.

Next screenshot is showing only one common element between users, the XAUTHORITY var...

I could use that but I think that could be a very dirty way to do it. It must be a better way. Any suggestion? Thanks.

Answer 1

The only reliable method is for you to obtain the report, from the environment by a non-root user ID , of the XDG_SESSION_TYPE variable's value.

• For X-Windows, XDG_SESSION_TYPE=x11
• For Wayland, XDG_SESSION_TYPE=wayland

However, as datenwolf stated, since root is specifically hindered by hard-coded security precautions , even if you customized your root's.bashrc, you won't be able to get the GUI to respond reliably, if at all, depending on the tools and elements you use.

If, on the other hand, you are attempting to build a tool for specific use by high-level security specialists, then you will likely require a customized build of the OS (removing those hard-coded security blocks) to complement those tools. That... is a huge task, which only those with deep pockets and unlimited resources... can allow themselves to contemplate... unless the developers were smart enough to anticipate such a need and have all those code segments "drop-out" during compilation with the appropriate compile-time flag turned on/off . :-)