FWIW I think OP is either trying to solve some sort of homework ("use a system call to ..."), which would point to a really bad teacher.
Or they think "system call" means using the C system("call").
If the latter, then of course the solutions given above using feh or gsettings (if applicable, i.e. in gnome or such) would do the trick nicely.
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I need a system call to change the desktop background
Re: I need a system call to change the desktop background
You are on the right track here. Don't need a root terminal for this, and you have to make the script executable. If you are tying to an event like opening and closing another application you could set the script in a systemd service and start and stop it, with the application open and close actions, or add the script to application open and close actions. No one can accurately help you with this until you define the event. What is the event? Unfortunately I don't use MATE and you seem over your head here. Sorry for any misunderstanding but gsettings utilizing the onboard wallpaper changer in an executable script is the way to go.gsettings set org.mate.background picture-filename /ddisk/f/scans/UpTrain.png
TC
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