Add idlelatency.sh script to measure an "idle" line (without sending any traffic)

Excerpted the -i tests from betterspeedtest.sh

idlelatency.sh

@@ -0,0 +1,172 @@
+#!/bin/sh
+
+# idlelatency.sh - Script to get latency statistics on an idle line
+# This script starts a ping, then collects statistics on the latency
+#   for a designated time period
+
+# Usage: sh idlelatency.sh [-4 -6] [ -t duration ] [ -p host-to-ping ] 
+
+# Options: If options are present:
+#
+# -4 | -6:       enable ipv4 or ipv6 testing (ipv4 is the default)
+# -t | --time:   Duration for how long each direction's test should run - (default - 60 seconds)
+# -p | --ping:   Host to ping to measure latency (default - gstatic.com)
+
+# Copyright (c) 2014-2020 - Rich Brown rich.brown@blueberryhillsoftware.com
+# GPLv2
+
+# Summarize the contents of the ping's output file to show min, avg, median, max, etc.
+#   input parameter ($1) file contains the output of the ping command
+
+summarize_pings() {     
+  
+  # Process the ping times, and summarize the results
+  # grep to keep lines that have "time=", then sed to isolate the time stamps, and sort them
+  # awk builds an array of those values, and prints first & last (which are min, max) 
+  # and computes average.
+  # If the number of samples is >= 10, also computes median, and 10th and 90th percentile readings
+
+  # stop pinging and drawing dots
+  kill_pings
+  kill_dots
+
+  sed 's/^.*time=\([^ ]*\) ms/\1/' < $1 | grep -v "PING" | sort -n | \
+  awk 'BEGIN {numdrops=0; numrows=0;} \
+    { \
+      if ( $0 ~ /timeout/ ) { \
+          numdrops += 1; \
+      } else { \
+        numrows += 1; \
+        arr[numrows]=$1; sum+=$1; \
+      } \
+    } \
+    END { \
+      pc10="-"; pc90="-"; med="-"; \
+      if (numrows == 0) {numrows=1} \
+      if (numrows>=10) \
+      {   ix=int(numrows/10); pc10=arr[ix]; ix=int(numrows*9/10);pc90=arr[ix]; \
+        if (numrows%2==1) med=arr[(numrows+1)/2]; else med=(arr[numrows/2]); \
+      }; \
+      pktloss = numdrops/(numdrops+numrows) * 100; \
+      printf("\n  Latency: (in msec, %d pings, %4.2f%% packet loss)\n      Min: %4.3f \n    10pct: %4.3f \n   Median: %4.3f \n      Avg: %4.3f \n    90pct: %4.3f \n      Max: %4.3f\n", numrows, pktloss, arr[1], pc10, med, sum/numrows, pc90, arr[numrows] )\
+     }'
+
+  # and finally remove the PINGFILE
+  rm $1
+
+}
+
+# Print a line of dots as a progress indicator.
+
+print_dots() {
+  while : ; do
+    printf "."
+    sleep 1s
+  done
+}
+
+# Stop the current print_dots() process
+
+kill_dots() {
+  # echo "Pings: $ping_pid Dots: $dots_pid"
+  kill -9 $dots_pid
+  wait $dots_pid 2>/dev/null
+  dots_pid=0
+}
+
+# Stop the current ping process
+
+kill_pings() {
+  # echo "Pings: $ping_pid Dots: $dots_pid"
+  kill -9 $ping_pid 
+  wait $ping_pid 2>/dev/null
+  ping_pid=0
+}
+
+# Stop the current pings and dots, and exit
+# ping command catches (and handles) first Ctrl-C, so you have to hit it again...
+kill_pings_and_dots_and_exit() {
+  kill_dots
+  kill_pings
+  echo "\nStopped"
+  exit 1
+}
+
+# ------------ start_pings() ----------------
+# Start printing dots, then start a ping process, saving the results to a PINGFILE
+
+start_pings() {
+
+  # Create temp file
+  PINGFILE=`mktemp /tmp/measurepings.XXXXXX` || exit 1
+
+  # Start dots
+  print_dots &
+  dots_pid=$!
+  # echo "Dots PID: $dots_pid"
+
+  # Start Ping
+  if [ $TESTPROTO -eq "-4" ]
+  then
+    ping  $PINGHOST > $PINGFILE &
+  else
+    ping6 $PINGHOST > $PINGFILE &
+  fi
+  ping_pid=$!
+  # echo "Ping PID: $ping_pid"
+
+}
+
+# ------- Start of the main routine --------
+
+# Usage: sh idlelatency.sh [ -4 -6 ] [ -t duration ] [ -p host-to-ping ]
+
+# -4 or -6 to control whether to use IPv4 or IPv6
+# “t” and “time” Time to run the test in each direction (default: 60 seconds)
+# “p” and “ping” Host to ping for latency measurements (default: gstatic.com)
+
+# set an initial values for defaults
+TESTDUR="60"
+PINGHOST="gstatic.com"
+TESTPROTO="-4"
+
+# read the options
+
+# extract options and their arguments into variables.
+while [ $# -gt 0 ] 
+do
+    case "$1" in
+      -4|-6) TESTPROTO=$1 ; shift 1 ;;
+      -t|--time) 
+        case "$2" in
+          "") echo "Missing duration" ; exit 1 ;;
+              *) TESTDUR=$2 ; shift 2 ;;
+          esac ;;
+      -p|--ping)
+          case "$2" in
+              "") echo "Missing ping host" ; exit 1 ;;
+              *) PINGHOST=$2 ; shift 2 ;;
+          esac ;;
+      --) shift ; break ;;
+        *) echo "Usage: sh idlelatency.sh [-4 -6] [ -t duration ] [ -p host-to-ping ]" ; exit 1 ;;
+    esac
+done
+
+# Start the main test
+
+if [ $TESTPROTO -eq "-4" ]
+then
+  PROTO="ipv4"
+else
+  PROTO="ipv6"
+fi
+DATE=`date "+%Y-%m-%d %H:%M:%S"`
+
+# Catch a Ctl-C and stop the pinging and the print_dots
+trap kill_pings_and_dots_and_exit HUP INT TERM
+
+echo "$DATE Testing idle line while pinging $PINGHOST ($TESTDUR seconds)"
+start_pings
+sleep $TESTDUR
+summarize_pings $PINGFILE
+