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diff --git a/trunk/ACE/ace/Dynamic_Service_Dependency.h b/trunk/ACE/ace/Dynamic_Service_Dependency.h
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+++ b/trunk/ACE/ace/Dynamic_Service_Dependency.h
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+// -*- C++ -*-
+
+//=============================================================================
+/**
+ *  @file    Dynamic_Service_Dependency.h
+ *
+ *  $Id$
+ *
+ *  @author Iliyan Jeliazkov <iliyan@ociweb.com>
+ */
+//=============================================================================
+
+#ifndef ACE_DYNAMIC_SERVICE_DEPENDENCY_H
+#define ACE_DYNAMIC_SERVICE_DEPENDENCY_H
+
+#include /**/ "ace/pre.h"
+
+
+#if !defined (ACE_LACKS_PRAGMA_ONCE)
+# pragma once
+#endif /* ACE_LACKS_PRAGMA_ONCE */
+
+#include "ace/Dynamic_Service_Base.h"
+#include "ace/Service_Object.h"
+#include "ace/DLL.h"
+
+ACE_BEGIN_VERSIONED_NAMESPACE_DECL
+
+/**
+ * @class ACE_Dynamic_Service_Dependency
+ *
+ * @brief Provides a way to declare dependency on specific service,
+ * thus helping to avoid order of initialization issues with instances
+ * of an objects whose implementation code resides in dynamically loaded
+ * services.
+ *
+ * It is disastrous to have dynamically loadable services create and give away
+ * ownership of objects and then ending up being unloaded before all those
+ * instances have been deleted. Normally the code for such objects classes
+ * resides within the TEXT segment of the DLL, which implements the service.
+ * If a service gets removed, its DLL may be unmapped from memory and then
+ * any attempt to invoke a method on the said objects will cause SEGV.
+ *
+ * Such instances must contain a member of ACE_Dynamic_Service_Dependency
+ * initialized with the service they depend on.
+ * ACE_Dynamic_Service_Dependency's constructor and destructor are
+ * "magical" - they work by maintaining the underlying dynamic service's
+ * DLL reference count.
+ */
+class ACE_Export ACE_Dynamic_Service_Dependency
+{
+public:
+  ACE_Dynamic_Service_Dependency  (const ACE_Service_Gestalt *cfg,
+                                   const ACE_TCHAR *principal);
+  ACE_Dynamic_Service_Dependency  (const ACE_TCHAR *principal);
+  ~ACE_Dynamic_Service_Dependency (void);
+
+private:
+  void init (const ACE_Service_Gestalt *cfg, const ACE_TCHAR *principal);
+
+private:
+  ACE_DLL tracker_;
+};
+
+ACE_END_VERSIONED_NAMESPACE_DECL
+
+
+#include /**/ "ace/post.h"
+
+#endif /* ACE_DYNAMIC_SERVICE_DEPENDENCY_H */