diff --git a/lib/System/Unix/Path.inc b/lib/System/Unix/Path.inc
index 184da1e27ac..4c97c4b71cc 100644
--- a/lib/System/Unix/Path.inc
+++ b/lib/System/Unix/Path.inc
@@ -439,7 +439,7 @@ Path::isDirectory() const {
   struct stat buf;
   if (0 != stat(path.c_str(), &buf))
     return false;
-  return buf.st_mode & S_IFDIR ? true : false;
+  return ((buf.st_mode & S_IFMT) == S_IFDIR) ? true : false;
 }
 
 bool