4 common ways of asynchronous execution in PHP

This article describes the php asynchronous calling method and shares it with you for your reference. The specific content is as follows
The client and the server communicate through the HTTP protocol. The client initiates a request, and the server performs processing after receiving the request. , and return the processing results.
Sometimes the server needs to perform a time-consuming operation, and the result of this operation does not need to be returned to the client. But because PHP is executed synchronously, the client needs to wait for the service to be processed before proceeding to the next step.
So time-consuming operations are suitable for asynchronous execution. After the server receives the request, it returns after processing the data required by the client, and then performs time-consuming operations asynchronously on the server.
1. Use Ajax and img tag
Principle, insert Ajax code or img tag into the HTML returned by the server, and the src of img is the program that needs to be executed.
Advantages: Simple to implement, the server does not need to perform any calls
Disadvantages: During execution, the browser will always be in the loading state, so this method is not a true asynchronous call.

$.get("doRequest.php", { name: "fdipzone"} );
<img src="doRequest.php&#63;name=fdipzone">

2. Use popen
Use popen to execute commands, syntax:

// popen — 打开进程文件指针  
resource popen ( string $command , string $mode )
pclose(popen('php /home/fdipzone/doRequest.php &', 'r'));

Advantages: Fast execution
Disadvantages:

• 1). Can only be executed on this machine
• 2). You cannot pass a large number of parameters
• 3). Many processes will be created when the traffic is high

3. Use curl
to set the curl timeout CURLOPT_TIMEOUT to 1 (the minimum is 1), so The client needs to wait for 1 second

<&#63;php 
$ch = curl_init(); 
$curl_opt = array( 
  CURLOPT_URL, 'http://www.example.com/doRequest.php'
  CURLOPT_RETURNTRANSFER,1, 
  CURLOPT_TIMEOUT,1 
); 
curl_setopt_array($ch, $curl_opt); 
curl_exec($ch); 
curl_close($ch); 
&#63;>

4. Using fsockopen
fsockopen is the best. The disadvantage is that you need to splice the header part yourself.

<&#63;php 
   
$url = 'http://www.example.com/doRequest.php'; 
$param = array( 
  'name'=>'fdipzone', 
  'gender'=>'male', 
  'age'=>30 
); 
   
doRequest($url, $param); 
   
function doRequest($url, $param=array()){ 
   
  $urlinfo = parse_url($url); 
   
  $host = $urlinfo['host']; 
  $path = $urlinfo['path']; 
  $query = isset($param)? http_build_query($param) : ''; 
   
  $port = 80; 
  $errno = 0; 
  $errstr = ''; 
  $timeout = 10; 
   
  $fp = fsockopen($host, $port, $errno, $errstr, $timeout); 
   
  $out = "POST ".$path." HTTP/1.1\r\n"; 
  $out .= "host:".$host."\r\n"; 
  $out .= "content-length:".strlen($query)."\r\n"; 
  $out .= "content-type:application/x-www-form-urlencoded\r\n"; 
  $out .= "connection:close\r\n\r\n"; 
  $out .= $query; 
   
  fputs($fp, $out); 
  fclose($fp); 
} 
   
?>

Note: During the execution process, the client connection is disconnected or the connection times out, which may cause incomplete execution, so you need to add

ignore_user_abort(true); // 忽略客户端断开 
set_time_limit(0);    // 设置执行不超时

The above is the php asynchronous calling method Detailed introduction, I hope it will be helpful to everyone's study.

The above introduces 4 common methods of PHP asynchronous execution, including aspects of content. I hope it will be helpful to friends who are interested in PHP tutorials.