! fix unbound variable: args[@]

Author: oldratlee

bin/xpl

@@ -75,14 +75,14 @@ while [ $# -gt 0 ]; do
         ;;
     --)
         shift
-        args=("${args[@]}" "$@")
+        args=(${args[@]:+"${args[@]}"} "$@")
         break
         ;;
     -*)
         usage 2 "${PROG}: unrecognized option '$1'"
         ;;
     *)
-        args=("${args[@]}" "$1")
+        args=(${args[@]:+"${args[@]}"} "$1")
         shift
         ;;
     esac