- implemented multi-line response in AsconStdHandler

ascon.h

@@ -84,4 +84,13 @@ char *ConcatArgs(int argc, char *argv[]);
  */
 double DoubleTime(void);
 
+/** \brief emit an error message. The state switches to AsconFailed.
+ *  \param a the connection
+ *  \param msg, a message to be emitted
+ *  \param errorno, for user messages, this should be 0. After
+ *         detection of a system error, eerno may be placed as argument
+ *         for adding strerror(errno) to the message.
+ */
+void AsconError(Ascon *a, char *msg, int errorno);
+
 #endif