但研究了一下nginx帮助后发现，有-s参数可对nginx服务进行管理：
# /usr/local/nginx/sbin/nginx -h
nginx version: nginx/0.7.63
Usage: nginx [-?hvVt] [-s signal] [-c filename] [-p prefix] [-g directives]

Options:
-?,-h : this help
-v : show version and exit
-V : show version and configure options then exit
-t : test configuration and exit
-s signal : send signal to a master process: stop, quit, reopen, reload
-p prefix : set prefix path (default: /usr/local/nginx/)
-c filename : set configuration file (default: conf/nginx.conf)
-g directives : set global directives out of configuration file

于是我执行
# /usr/local/nginx/sbin/nginx -s reload
nginx已经重启成功

用root权限

#killall nginx

#nginx

其它相关命令：

1.显示nginx进行id
#ps -aux | grep nginx

2.结果nginx的master进行pid
#kill -HUP 635

3.重启ngnix
#nginx