CODE EXAMPLE FOR SHELL

check if internet is available shell script

test=google.com
if nc -zw1 $test 443 && echo |openssl s_client -connect $test:443 2>&1 |awk '
  handshake && $1 == "Verification" { if ($2=="OK") exit; exit 1 }
  $1 $2 == "SSLhandshake" { handshake = 1 }'
then
  echo "we have connectivity"
fi