curl_multi_exec

PHP
$nodes = array('http://www.google.com', 'http://www.microsoft.com', 'http://www.rustyrazorblade.com');
$node_count = count($nodes);

$curl_arr = array();
$master = curl_multi_init();

for($i = 0; $i < $node_count; $i++)
{
    $url =$nodes[$i];
    $curl_arr[$i] = curl_init($url);
    curl_setopt($curl_arr[$i], CURLOPT_RETURNTRANSFER, true);
    curl_multi_add_handle($master, $curl_arr[$i]);
}

do {
    curl_multi_exec($master,$running);
} while($running > 0);

echo "results: ";
for($i = 0; $i < $node_count; $i++)
{
    $results = curl_multi_getcontent  ( $curl_arr[$i]  );
    echo( $i . "\n" . $results . "\n");
}
echo 'done';
Source

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