【curl 检测网站访问状态】curl -o /dev/null -s -w "HTTP状态码: %{http_code}\nDNS解析: %{time_namelookup}秒\nTCP连接: %{time_connect}秒\nSSL握手: %{time_appconnect}秒\n首字节时间: %{time_starttransfer}秒\n总时间: %{time_total}秒\n" https://github.com
