sway: improved random wallpaper script and minimized side effects

homeManagerModules/desktop/sway/randomWallpaper.nix

@@ -5,16 +5,27 @@
   ...
 }: let
   sway-randomWallpaper = pkgs.writeShellScriptBin "sway-randomWallpaper" ''
+    kill `pidof swaybg`
+
+    OLD_PIDS=()
     directory=${config.home.homeDirectory}/.local/share/backgrounds
 
     if [ -d "$directory" ]; then
         while true; do
-          kill `pidof swaybg`
+
+          for pid in ''${OLD_PIDS[@]}; do
+            kill $pid
+          done
+          OLD_PIDS=()
+
           monitor=`${config.wayland.windowManager.sway.package}/bin/swaymsg -t get_outputs -p | grep Output | awk '{print $2}'`
+          
           for m in ''${monitor[@]}; do
             random_background=$(ls $directory/*.{png,jpg} | shuf -n 1)
             ${pkgs.swaybg}/bin/swaybg -o $m -i $random_background &
+            OLD_PIDS+=($!)
           done
+
           sleep 900
         done
     fi