Using curl_multi_close() to Properly Close Multiple cURL Sessions in PHP

When making network requests in PHP, the cURL library is commonly used, and the curl_multi_close() function is essential for closing multiple cURL sessions.

The curl_multi_close() function releases resources allocated by curl_multi_init() , and calling it after all requests have been processed is good practice.

Example code demonstrates creating a multi‑handle with curl_multi_init() , adding two individual requests via curl_init() and curl_multi_add_handle() , and finally closing the multi‑handle with curl_multi_close() .

<?php
// 创建多个cURL会话
$multiHandle = curl_multi_init();
// 添加第一个请求
$ch1 = curl_init();
curl_setopt($ch1, CURLOPT_URL, 'https://example.com/api/1');
curl_setopt($ch1, CURLOPT_RETURNTRANSFER, true);
curl_multi_add_handle($multiHandle, $ch1);
// 添加第二个请求
$ch2 = curl_init();
curl_setopt($ch2, CURLOPT_URL, 'https://example.com/api/2');
curl_setopt($ch2, CURLOPT_RETURNTRANSFER, true);
curl_multi_add_handle($multiHandle, $ch2);
// 执行并等待所有请求完成
// ...
// 关闭会话
curl_multi_close($multiHandle);
?>

The example explains each step: initializing the multi‑handle, setting up separate cURL handles, adding them to the multi‑handle, executing the requests, and closing the handle to free resources.

In summary, curl_multi_close() reliably terminates the sessions created by curl_multi_init() , ensuring timely resource release and improved performance for network‑intensive PHP applications.