diff --git a/utils/cloudio/SMFileSystem.cpp b/utils/cloudio/SMFileSystem.cpp
index 02341fa46..4da45e4d9 100644
--- a/utils/cloudio/SMFileSystem.cpp
+++ b/utils/cloudio/SMFileSystem.cpp
@@ -45,7 +45,7 @@ off64_t SMFileSystem::size(const char *filename) const
     
     SMComm *smComm = SMComm::get();
     int err = smComm->stat(filename, &_stat);
-    if (!err)
+    if (err)
         return err;
     
     return _stat.st_size;
diff --git a/utils/cloudio/component_test.cpp b/utils/cloudio/component_test.cpp
index 47b32f0f2..f54b4968c 100644
--- a/utils/cloudio/component_test.cpp
+++ b/utils/cloudio/component_test.cpp
@@ -87,7 +87,7 @@ void error_server_thread()
                 continue;
             }
             else {
-                char errbuf[80];
+                //char errbuf[80];
                 //cout << "server thread got an error: " << strerror_r(errno, errbuf, 80) << endl;
                 close(client_socket);
                 errCode = -1;
@@ -151,6 +151,15 @@ int test1()
     }
     assert(gotException && !die);
     
+    cout << "rename" << endl;
+    try {
+        filesystem.rename("dummy1", "dummy2");
+    }
+    catch (NotImplementedYet &) {
+        gotException = true;
+    }
+    assert(gotException && !die);
+    
     cout << "exists" << endl;
     err = filesystem.exists("dummy");
     assert(!err);
@@ -168,6 +177,18 @@ int test1()
     err = filesystem.listDirectory("dummy", filenames);
     assert(err == -1 && filenames.empty() && !die);
     
+    cout << "remove" << endl;
+    err = filesystem.remove("dummy");
+    assert(err == -1 && !die);
+    
+    cout << "size" << endl;
+    err = filesystem.size("dummy");
+    assert(err == -1 && !die);
+    
+    cout << "mkdir" << endl;
+    err = filesystem.mkdir("dummy");
+    assert(err == 0 && !die);
+    
     // done, return errCode
     die = true;
     server_thread.join();