Merge pull request #376 from cdburkard/patches/pingOutput

if we do not receive a ping and cannot parse output, return errorTuple

mininet/net.py

@@ -603,6 +603,8 @@ def _parsePingFull( pingOutput ):
         r += r'(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+) ms'
         m = re.search( r, pingOutput )
         if m is None:
+            if received == 0:
+                return errorTuple
             error( '*** Error: could not parse ping output: %s\n' %
                    pingOutput )
             return errorTuple