Workspace changes don't seem to be detectable by wmctrl

[mbert]

If I want to bind actions to workspace change events (like setting wallpapers by workspace using feh), these events should be detectable by the usual tooling for this. I tried wmctrl, but it failed to catch anything. I am not deeply familiar with the window manager standards relevant for this stuff, maybe I need to use another tool for this, nevertheless seems worth mentioning.

[trunkmaster]

I guess that wmctl tool behaviour is out of scope of this project.
But, out of curiosity, what option of wmctrl do you use to detect workspace changes?

[mbert]

What I tried to do is rung wmctrl -d ("List desktops. The current desktop is marked"). In order to set wallpapers by desktop I'd write a shell script to run in the background checking whether the desktop has changed and if yes, run feh to set the wallpaper for that desktop.

However the call fails with this message:

Cannot get current desktop properties. (_NET_CURRENT_DESKTOP or _WIN_WORKSPACE property)