As far as I can tell, the only way to reload the background shader without restarting driftwm is to edit the shader path to something else and then change it back. This makes it a bit frustrating to test changes to one's shader.

Instead, would it be possible to do one of the following?

1. always reload the shader when the config is changed (so that touching the config would be sufficient to trigger a reload)
2. detect the shader has been changed on-disk, and reload it
3. add a hotkey/command for reloading the current shader or doing a "hard reload" of the entire config