fix traffic generator output parsing

refs #2832

Change-Id: If00b8afb8855ec1cf33bcd8100c89c22656e486e
diff --git a/test_localhop/localhop-test.sh b/test_localhop/localhop-test.sh
index 2289722..19aa099 100755
--- a/test_localhop/localhop-test.sh
+++ b/test_localhop/localhop-test.sh
@@ -82,7 +82,7 @@
 # analyze server log
 echo "analyzing server log..."
 output=$(grep "Total Interests Received" $workdir/logs/server.log | head -2 | tail -1 | cut -d= -f2 | cut -d' ' -f2)
-if [ $output != '0' ]
+if [ $output != 0?(.+(0)) ]
 then
     echo "Expected no interests with name ndn:/localhop/test-localhop/A/1 received on host C. Actual: $output"
     echo "For more information, please examine the log at \"$(pwd)/logs\""