Shell function to check if Internet access is available.
#!/usr/bin/env bash
checkInternet()
{
echo -e "GET http://google.com HTTP/1.0\n\n" | nc google.com 80 > /dev/null 2>&1 # query google with a get request
if [ $? -eq 0 ]; then #check if the output is 0, if so no errors have occured and we have connected to google successfully
return 0
else
echo "Error: no active internet connection" >&2 #sent to stderr
return 1
fi
}
# Usage:
checkInternet || exit 1