Keep pinging google.com and beep on success, so I know my flaky connection is working again

beepWhenInternet

#!/bin/bash
echo pinging google.com, will exit on success
echo ctrl+c to force exit
echo will beep on exit
echo

ping_cancelled=false                                              # Keep track of whether the loop was cancelled, or succeeded
until ping -c1 google.com >/dev/null 2>&1; do sleep 60; done &    # The "&" backgrounds it

trap "kill $!; ping_cancelled=true" SIGINT
wait $!                                                           # Wait for the loop to exit, one way or another
trap - SIGINT                                                     # Remove the trap, now we're done with it

if command -v speaker-test &> /dev/null                         # Ubuntu
    echo "(the 'speaker-test killed' messages are normal)"
fi

for i in {1..3}
do
  if command -v speaker-test &> /dev/null                         # Ubuntu-tested (18.04.4)
  then
    ( speaker-test -t sine -f 1000 >/dev/null)& pid=$! ; sleep 0.18s ; kill -9 $pid    # This beeps
    sleep 0.1s
  elif command -v afplay &> /dev/null
  then
    afplay /System/Library/Sounds/Glass.aiff                      # OSX-tested (El Capitan)
  fi
done

echo
echo "Done pinging, cancelled=$ping_cancelled"

# https://serverfault.com/questions/42021/how-to-ping-in-linux-until-host-is-known
# https://superuser.com/questions/598783/play-sound-on-mac-terminal
# https://stackoverflow.com/questions/592620/how-can-i-check-if-a-program-exists-from-a-bash-script