1 files changed, 6 insertions, 1 deletions
diff --git a/cpp/src/qpid/sys/BlockingQueue.h b/cpp/src/qpid/sys/BlockingQueue.h
index c53949ad6f..44c95b225d 100644
--- a/cpp/src/qpid/sys/BlockingQueue.h
+++ b/cpp/src/qpid/sys/BlockingQueue.h
@@ -32,7 +32,7 @@ namespace sys {
 template <class T>
 class BlockingQueue
 {
-    sys::Waitable lock;
+    mutable sys::Waitable lock;
     std::queue<T> queue;
     bool closed;
 
@@ -95,6 +95,11 @@ public:
         closed=false;
     }
 
+    bool isClosed() const { 
+        Waitable::ScopedLock l(lock);
+        return closed;
+    }
+    
   private:
 
     void queueNotify(size_t ignore) {