Use Curl, socket, file_get_contents three methods to POST data in PHP_PHP tutorial

/**
* Socket version
* Usage:
* $post_string = "app=socket&version=beta";
* request_by_socket('jb51.net','/restServer.php',$post_string) ;
*/
function request_by_socket($remote_server,$remote_path,$post_string,$port = 80,$timeout = 30){
$socket = fsockopen($remote_server,$port,$errno,$errstr,$timeout);
if (!$socket) die("$errstr($errno)");
fwrite($socket,"POST $remote_path HTTP/1.0");
fwrite($socket,"User-Agent: Socket Example");
fwrite($socket,"HOST: $remote_server");
fwrite($socket,"Content-type: application/x-www-form-urlencoded");
fwrite($socket,"Content-length: ".strlen($post_string)+8."");
fwrite($socket,"Accept:*/*");
fwrite($socket,"");
fwrite($socket,"mypost=$post_string");
fwrite($socket,"");
$header = "";
while ($str = trim(fgets($socket,4096))) {
$header.=$str;
}
$data = "";
while (!feof($socket)) {
$data .= fgets($socket,4096);
}
return $data;
}
/**
* Curl version
* Usage:
* $post_string = "app=request&version=beta";
* request_by_curl('http://jb51.net/restServer.php',$post_string );
*/
function request_by_curl($remote_server,$post_string){
$ch = curl_init();
curl_setopt($ch,CURLOPT_URL,$remote_server);
curl_setopt($ch,CURLOPT_POSTFIELDS,'mypost='.$post_string);
curl_setopt($ch,CURLOPT_RETURNTRANSFER,true);
curl_setopt($ch,CURLOPT_USERAGENT,"Jimmy's CURL Example beta");
$data = curl_exec($ch);
curl_close($ch);
return $data;
}
/**
* Other versions
* Usage:
* $post_string = "app=request&version=beta";
* request_by_other('http://jb51.net/restServer.php',$post_string );
*/
function request_by_other($remote_server,$post_string){
$context = array(
'http'=>array(
'method'=>'POST',
'header'=>'Content-type: application/x-www-form-urlencoded'."".
'User-Agent : Jimmy's POST Example beta'."".
'Content-length: '.strlen($post_string)+8,
'content'=>'mypost='.$post_string)
);
$stream_context = stream_context_create($context);
$data = file_get_contents($remote_server,FALSE,$stream_context);
return $data;
}
?>