Modify wrapper script to pass tx buffer len option

scripts/run_client

@@ -14,8 +14,11 @@ interval=100000
 client_options="-a -p 99 -f eth0"
 qdisc_options=""
 
-while getopts "e:i:pt" opt; do
+while getopts "d:e:i:pt" opt; do
   case "${opt}" in
+    d )
+        client_options+=" -d ${OPTARG}"
+        ;;
     e )
         use_etf=1
         client_options+=" -e -q 7"