PIEthernet TCP improvements

git-svn-id: svn://db.shs.com.ru/pip@131 12ceb7fc-bf1f-11e4-8940-5bc7170c53b5

src/core/pistring.h

@@ -115,7 +115,7 @@ public:
 	//~PIString() {piMonitor.strings--; piMonitor.containers++;}
 
 
-	PIString & operator =(const PIString & o) {clear(); *this += o; return *this;}
+	PIString & operator =(const PIString & o) {if (this == &o) return *this; clear(); *this += o; return *this;}
 
 	/*! \brief Return c-string representation of string
 	 * \details Converts content of string to c-string and return