配置nginx时一直报错：file not found

错误日志：

[error] 12691#0: *6 FastCGI sent in stderr: "Primary script unknown" while reading response header from upstream, client: 192.168.168.1, server: localhost, request: "GET / HTTP/1.1", upstream: "fastcgi://127.0.0.1:9000", host: "192.168.168.133"

改成下面的配置恢复正常，/datao/htdocs/thinkphp为根目录

{    listen          80;    server_name     www.tp.com;    access_log      /data1/logs/tp_access.log myformat;    index index.html index.htm index.php;    root    /datao/htdocs/thinkphp;    location ~ \.php    {            fastcgi_index index.php;            fastcgi_pass 127.0.0.1:9000;            include      fastcgi_params;            set $path_info "";            set $real_script_name $fastcgi_script_name;            if ($fastcgi_script_name ~ "^(.+?\.php)(/.+)$") {                    set $real_script_name $1;                    set $path_info $2;            }            fastcgi_param SCRIPT_FILENAME /data0/htdocs/thinkphp/$real_script_name;            fastcgi_param SCRIPT_NAME $real_script_name;            fastcgi_param PATH_INFO $path_info;    }               }