PHP CURL或file_get_contents获取网页标题的代码及两者效率的稳定性问题

<?php
$c = curl_init();
$url = 'www.jb51.net';
curl_setopt($c, CURLOPT_URL, $url);
curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
$data = curl_exec($c);
curl_close($c);
$pos = strpos($data,'utf-8');
if($pos===false){$data = iconv("gbk","utf-8",$data);}
preg_match("/<title>(.*)<＼/title>/i",$data, $title);
echo $title[1];
?>

<?php
$content=file_get_contents("https://www.jb51.net/");
$pos = strpos($content,'utf-8');
if($pos===false){$content = iconv("gbk","utf-8",$content);}
$postb=strpos($content,'<title>')+7;
$poste=strpos($content,'</title>');
$length=$poste-$postb;
echo substr($content,$postb,$length);
?>

<?php
/**
* 通过淘宝IP接口获取IP地理位置
* @param string $ip
* @return: string
**/
function getCityCurl($ip)
{
 $url="http://ip.taobao.com/service/getIpInfo.php?ip=".$ip;
 $ch = curl_init();
 $timeout = 5;
 curl_setopt ($ch, CURLOPT_URL, $url);
 curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
 curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, $timeout);
 $file_contents = curl_exec($ch);
 curl_close($ch);
 $ipinfo=json_decode($file_contents);
 if($ipinfo->code=='1'){
  return false;
 }
 $city = $ipinfo->data->region.$ipinfo->data->city;
 return $city;
}
function getCity($ip)
{
 $url="http://ip.taobao.com/service/getIpInfo.php?ip=".$ip;
 $ipinfo=json_decode(file_get_contents($url));
 if($ipinfo->code=='1'){
  return false;
 }
 $city = $ipinfo->data->region.$ipinfo->data->city;
 return $city;
}
// for file_get_contents
$startTime=explode(' ',microtime());
$startTime=$startTime[0] + $startTime[1];
for($i=1;$i<=10;$i++)
{
 echo getCity("121.207.247.202")."</br>";
}
$endTime = explode(' ',microtime());
$endTime = $endTime[0] + $endTime[1];
$totalTime = $endTime - $startTime;
echo 'file_get_contents:'.number_format($totalTime, 10, '.', "")." seconds</br>";
//for curl
$startTime2=explode(' ',microtime());
$startTime2=$startTime2[0] + $startTime2[1];
for($i=1;$i<=10;$i++)
{
 echo getCityCurl('121.207.247.202')."</br>";
}
$endTime2 = explode(' ',microtime());
$endTime2=$endTime2[0] + $endTime2[1];
$totalTime2 = $endTime2 - $startTime2;
echo "curl:".number_format($totalTime2, 10, '.', "")." seconds";
?>

function curl_get_contents($url) 
{ 
 $ch = curl_init(); 
 curl_setopt($ch, CURLOPT_URL, $url);   //设置访问的url地址 
 //curl_setopt($ch,CURLOPT_HEADER,1);   //是否显示头部信息 
 curl_setopt($ch, CURLOPT_TIMEOUT, 5);   //设置超时 
 curl_setopt($ch, CURLOPT_USERAGENT, _USERAGENT_); //用户访问代理 User-Agent 
 curl_setopt($ch, CURLOPT_REFERER,_REFERER_);  //设置 referer 
 curl_setopt($ch,CURLOPT_FOLLOWLOCATION,1);  //跟踪301 
 curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);  //返回结果 
 $r = curl_exec($ch); 
 curl_close($ch); 
 return $r; 
}