Distinguishing curl client and server errors

gistfile1.txt

function curl_client_error() {
    if [ "$2" == "4" ]; then
        echo $1: Error resolving proxy
    elif [ "$2" == "6" ]; then
        echo $1:    Error resolving host
    elif [ "$2" == "7" ]; then
        echo $1: Error connecting to host
    elif [ "$2" == "28" ]; then
        echo $1: Server response timed out. 
    fi
}

function curl_server_error() {
    if [ $2  -ge 400 ]; then
        echo $1: Error [$2] from server
    fi
}


curl --connect-timeout 3 --max-time 2 httpstat.us/200?sleep=5000 2> /dev/null 2>&1
curl_client_error "Client" $?

# Client: Server response timed out.

response=$(curl --connect-timeout 3 --max-time 2 --write-out %{http_code} --silent --output /dev/null https://httpstat.us/502)
curl_server_error "Server" $response

#Server: Error [502] from server