pm3: textual and --list with no device, exit 1

pm3

@@ -338,7 +338,7 @@ done
 if [ "$1" == "--list" ]; then
     shift
     if [ "$1" != "" ]; then
-        echo "Option --list must be used alone"
+        echo "[!!] Option --list must be used alone"
         exit 1
     fi
     SHOWLIST=true
@@ -352,7 +352,7 @@ if [ "$1" == "-n" ]; then
         N=$1
         shift
     else
-        echo "Option -n requires a number between 1 and 9, got \"$1\""
+        echo "[!!] Option -n requires a number between 1 and 9, got \"$1\""
         exit 1
     fi
 fi
@@ -363,7 +363,7 @@ if [ "$HOSTOS" = "LINUX" ]; then
         # Test presence of wmic
         wmic.exe computersystem get name >/dev/null 2>&1
         if [ $? -ne 0 ]; then
-            echo "[!] Cannot run wmic.exe, are you sure your WSL is authorized to run Windows processes? (cf WSL interop flag)"
+            echo "[!!] Cannot run wmic.exe, are you sure your WSL is authorized to run Windows processes? (cf WSL interop flag)"
             exit 1
         fi
         GETPM3LIST=get_pm3_list_WSL
@@ -384,7 +384,7 @@ if $SHOWLIST; then
     $GETPM3LIST 9
     if [ ${#PM3LIST} -lt 1 ]; then
         echo "[!!] No port found"
-        exit 0
+        exit 1
     fi
     n=1
     for DEV in ${PM3LIST[@]}