How to get multi curl return (curl_multi_add_handle)?

First, curl_multi is not "compatible" with the curl_* functions. That is, first you create cURL normally (using curl_init() and curl_setopt() ), then add this cURL handle in curl_multi_add_handle .

Since you have curl_multi_init , you should only use curl_multi_* functions.

To run:

curl_multi_exec()

But, it has a "mystery" because the documentation itself will do the CPU go to 100% , or even enter an infinite loop.

There are two ways to contain this, using:

$executando = 1;
while($executando > 0){
    curl_multi_exec($mh, $executando);
    curl_multi_select($mh);
}

Another option would be to use usleep :

$executando = 1;
while($running > 0){
    curl_multi_exec($mh, $executando);
    usleep(10);
}

Now how do I get the return, since all are within curl_multi_exec ? There are other functions in comparison:

CURL                                   CURL MULTI 

curl_exec()                            curl_multi_exec()
                                       curl_multi_getcontent()

curl_close()                           curl_multi_remove_handle()
                                       curl_multi_close()

To get curl_getinfo you can directly use curl_getinfo($ch) itself, now if you want to get cURL Multi information, use curl_multi_info_read($mh) instead.

In one usage example, getting content from multiple pages:

// Cria o primeiro cURL
$ch1 = curl_init('https://jsonplaceholder.typicode.com/posts/1');
curl_setopt_array($ch1, [
    CURLOPT_SSLVERSION => CURL_SSLVERSION_TLSv1_2,
    CURLOPT_SSL_VERIFYHOST => 2,
    CURLOPT_SSL_VERIFYPEER => 0,  // Isto é inseguro, não use isto em produção, altere para '1'.
    CURLOPT_PROTOCOLS => CURLPROTO_HTTPS,
    CURLOPT_FOLLOWLOCATION => 1,
    CURLOPT_RETURNTRANSFER => 1
]);

// Copia o primeiro cURL e muda a URL, criando um segundo cURL
$ch2 = curl_copy_handle($ch1);
curl_setopt($ch2, CURLOPT_URL, 'https://api.fixer.io/latest');

// Cria o cURL Multi
$mh = curl_multi_init();

// Importa os cURL criados
curl_multi_add_handle($mh,$ch1);
curl_multi_add_handle($mh,$ch2);

// Executa o cURL Multi
$running = 1;

while($running > 0){
    curl_multi_exec($mh, $running);
    curl_multi_select($mh);
}

// Exibe primeiro cURL:
echo curl_multi_getcontent($ch1);

// Exibe segundo cURL:
echo curl_multi_getcontent($ch2);

// Fecha o cURL Multi:
curl_multi_close($mh);

// Fecha o cURL:
curl_close($ch1);
curl_close($ch2);

This will return two JSON, distinct, one is from this page and the other this .