Fail if -i arg is not .service

admin/checkservices

@@ -252,7 +252,7 @@ usage() {
     echo "  -s/-S: display (or not) status of restarted service (default: $STATUS)" >&2
     echo "  -u/-U: act (or not) on services in users slice (default: $USER_SLICE)" >&2
     echo "  -z/-Z: serialize (or not) action (default: $SERIALIZE)" >&2
-    echo "  -i 'service_name'.service: list of services to ignore (space separated)" >&2
+    echo "  -i 'service_name'.service: ignore a specific service (can be used multiple times)" >&2
     exit 2
 }
 
@@ -272,6 +272,8 @@ argparse() {
             Z) SERIALIZE=0;;        z) SERIALIZE=1;;
 	    i) if [[ "$OPTARG" == *.service ]]; then
                     IGNORED_SERVICES+=("$OPTARG")
+	       else
+		    usage
                fi
                ;;
             *) usage;;