curl -I -m 10 -o /dev/null -s -w %{http_code} www.d0o0bz.cn

-I, --head Show document info only 仅测试HTTP头
-m, --max-time SECONDS Maximum time allowed for the transfer
-m 10 最多查询10s
-o, --output FILE Write output to instead of stdout
-o /dev/null 屏蔽原有输出信息
-s, --silent Silent mode. Don’t output anything
-w, --write-out FORMAT What to output after completion
-w %{http_code} 控制额外输出

ECMBP:Desktop e.c.$ curl -I -m 10 -o /dev/null -s -w %{http_code} d0o0bz.cn 
200