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

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.