./nginx  #打开 nginx
nginx -s reload|reopen|stop|quit  #重新加载配置|重启|停止|退出 nginx
nginx -t   #测试配置是否有语法错误nginx [-?hvVtq] [-s signal] [-c filename] [-p prefix] [-g directives]-?,-h           : 打开帮助信息
-v              : 显示版本信息并退出
-V              : 显示版本和配置选项信息，然后退出
-t              : 检测配置文件是否有语法错误，然后退出
-q              : 在检测配置文件期间屏蔽非错误信息
-s signal       : 给一个 nginx 主进程发送信号：stop（停止）, quit（退出）, reopen（重启）, reload（重新加载配置文件）
-p prefix       : 设置前缀路径（默认是：/usr/local/nginx/）
-c filename     : 设置配置文件（默认是：/usr/local/nginx/conf/nginx.conf）
-g directives   : 设置配置文件外的全局指令

-s signal      Send a signal to the master process.  The argument signal can be one of: stop, quit, reopen, reload.The following table shows the corresponding system signals:stop    SIGTERMquit    SIGQUITreopen  SIGUSR1reload  SIGHUPSIGNALSThe master process of nginx can handle the following signals:SIGINT, SIGTERM  Shut down quickly.SIGHUP           Reload configuration, start the new worker process with a new configuration, and gracefully shutdown old worker processes.SIGQUIT          Shut down gracefully.SIGUSR1          Reopen log files.SIGUSR2          Upgrade the nginx executable on the fly.SIGWINCH         Shut down worker processes gracefully.

$ ps -ef|grep nginx
root      5747     1  0 May23 ?        00:00:00 nginx: master process /usr/local/nginx/sbin/nginx
500      12037  7886  0 10:00 pts/1    00:00:00 grep nginx
nobody   25581  5747  0 Sep27 ?        00:01:16 nginx: worker process
nobody   25582  5747  0 Sep27 ?        00:01:25 nginx: worker process
nobody   25583  5747  0 Sep27 ?        00:02:59 nginx: worker process
nobody   25584  5747  0 Sep27 ?        00:02:05 nginx: worker process

$ kill -9 5747

$ ./nginx -t…… nginx.conf syntax is ok…… nginx.conf test is successful

# ./nginx -s reload
或者
# kill -HUP 5747