1 files changed, 1 insertions, 1 deletions
diff --git a/src/serialize.h b/src/serialize.h
index 55b6891394..d8f0b76d59 100644
--- a/src/serialize.h
+++ b/src/serialize.h
@@ -1122,7 +1122,7 @@ public:
     FILE& operator*()           { return *file; }
     FILE** operator&()          { return &file; }
     FILE* operator=(FILE* pnew) { return file = pnew; }
-    bool operator!()            { return (file == NULL); }
+    bool IsNull() const         { return (file == NULL); }
 
 
     //