php模拟get_headers函数：php自定义get_headers函数

<?php
if(!function_exists('get_headers')){
function get_headers($url,$format=0){
$url=parse_url($url);
$end="rnrn";
$fp=fsockopen($url['host'],(empty($url['port'])?80:$url['port']),$errno,$errstr,30);
if($fp){
$out="GET / HTTP/1.1rn";
$out.="Host: ".$url['host']."rn";
$out.="Connection: Closernrn";
$var='';
fwrite($fp,$out);
while(!feof($fp)){
$var.=fgets($fp,1280);
if(strpos($var,$end))
break;
}
fclose($fp);
$var=preg_replace("/rnrn.*$/",'',$var);
$var=explode("rn",$var);
if($format){
foreach($var as $i){
if(preg_match('/^([a-zA-Z -]+): +(.*)$/',$i,$parts))
   $v[$parts[1]]=$parts[2];
}
  return $v;
}else{
  return $var;
}
}
}
}
echo '<pre>';
print_r(get_headers('http://www.jb200.com/article/49.html'));