Squashed commit of the following:

commit 53fd7c47
Author: Johan Hugé <johan.huge@nexedi.com>
Date:   Wed Jun 24 13:58:00 2020 +0200

    Set ETF delta in microseconds instead of nanoseconds in the wrapper script

commit 923296b7
Author: Johan Hugé <johan.huge@nexedi.com>
Date:   Wed Jun 24 11:25:57 2020 +0200

    Set flag enabling error report in error socket queue

packet-exchange/src/send_packet.c

@@ -96,7 +96,7 @@ void init_udp_send(egress_param_t *_params,
 
   if (params->use_etf) {
     sk_txtime.clockid = CLOCK_TAI;
-    sk_txtime.flags = 0;
+    sk_txtime.flags = SOF_TXTIME_REPORT_ERRORS;
 
     if (setsockopt(sock_fd, SOL_SOCKET, SO_TXTIME, &sk_txtime, sizeof(sk_txtime)))
       error(EXIT_FAILURE, errno, "setsockopt SO_TXTIME failed\n");

scripts/run_client

@@ -26,7 +26,7 @@ while getopts "bd:e:o:ghi:p" opt; do
         ;;
     e )
         use_etf=1
-        delta=${OPTARG}
+        delta=$((${OPTARG}*1000))
         qdisc_options+="-e $delta"
         ;;
     o )