Finalized script and added synopsis

Task_scripts/Linux - Schedule agent update.sh

@@ -1,4 +1,33 @@
 #!/bin/bash
+# Usage: "Linux - Schedule agent update.sh"
+# 
+# Description:
+#   This script is used from inside of Tactical RMM instances to schedule an update of a linux agent. 
+#   The script will download the update script and schedule it to run after 2 minutes, 
+#   this is done because the update script needs to stop and replace the agent files on the host.
+#
+# Options:
+#   n/a
+#
+# Author: D. de Kooker (info@dcomputers.nl)
+# Sources: n/a
+
+#Check if at is installed in order to schedule the update script
+check_at=$(which at 2> /dev/null)
+if [[ $check_at == "" || $check_at =~ .*"no at".* ]]; then
+        echo "'at' could not be found. Trying to install automatically."
+        if [[ `which yum` ]]; then
+                yum -y install at
+                echo "'at' command installed successfully."
+        elif [[ `which apt` ]]; then
+                apt-get -y update
+                apt-get -y install at
+                echo "'at' command installed successfully."
+        else
+                echo "Failed to install 'at' command. Please install it manually."
+        fi
+        exit 1
+fi
 
 # GitHub script URL
 GITHUB_URL="https://gittea.dannydekooker.nl/Dcomputers/TacticalRMM_Scripts/raw/branch/main/Supporting_scripts/Linux%20-%20Update%20TRMM%20agent.sh"
@@ -7,7 +36,7 @@ GITHUB_URL="https://gittea.dannydekooker.nl/Dcomputers/TacticalRMM_Scripts/raw/b
 DEST_DIR="/tmp"
 
 # Name of the script file
-SCRIPT_FILE="trmm-agentupdate.sh"
+SCRIPT_FILE="temp-trmm-agentupdate.sh"
 
 # Download the script from GitHub
 wget -O "$DEST_DIR/$SCRIPT_FILE" "$GITHUB_URL"
@@ -18,6 +47,12 @@ if [ $? -eq 0 ]; then
   # Schedule the script to run after 2 minutes
   echo "bash $DEST_DIR/$SCRIPT_FILE update amd64" | at now + 2 minutes
   echo "Script scheduled to run after 2 minutes."
+
+  # Schedule Cleanup of the update script
+  echo "rm -rf $DEST_DIR/$SCRIPT_FILE" | at now + 15 minutes
+  
+  exit 1
 else
   echo "Failed to download the script from GitHub."
+  exit 0
 fi