PHP获取关键词的百度排名，file_get_contents老提示failed?报错

PHP获取关键词的百度排名，file_get_contents老提示failed to open stream: HTTP request failed!请问如何解决，看了好多网上资料，配置php.in还是不行

下面是我从网上找到的一段代码

<?php
function getbaiduRank($key,$weburl)//关键词,网址
{
   //$newkey = iconv ('utf-8','gb2312',$key);
 $newkey =$key;
 $newkey = urlencode($newkey);
 $url = "http://www.baidu.com/s?ie=gb2312&wd=$newkey&rn=30";
 $content = str_replace('<table border="0" cellpadding="0" cellspacing="0"',
'<table cellpadding="0" cellspacing="0"',file_get_contents($url));
 $arr = array();
 $arr = explode ('class=m>推广',$content);//排除推广  
 $shuliang=count($arr);  
 //print_r ($arr[$shuliang-1]);
 $arr = explode ('<br clear=all>',$arr[$shuliang-1]);//去除尾部  
 $arr = explode ('<table cellpadding="0" cellspacing="0" id="',$arr[0]);
 $shuliang=count($arr);
 $paiming=0;
 for ($i=1;$i<$shuliang;$i++){if (strpos($arr[$i],$weburl)>0) {$paiming=$i;break;}}
 echo "关键词:".urldecode($newkey)."|网站:".$weburl."百度排名:".$paiming;
}
getbaiduRank('oscphp','http://www.oscphp.com');
?>

运行后就报错

Warning: file_get_contents(http://www.baidu.com/s?ie=gb2312&wd=oscphp&rn=30): failed to open stream: HTTP request failed! in E:\xampp\htdocs\ceshi.php on line 8 关键词:oscphp|网站:http://www.oscphp.com百度排名:0