php多线程下载远程多个文件的函数

以下代码，实现：多线程下载远程多个文件，如下：

 $v) {
if (!empty($v) && preg_match("~^http~i", $v)) {
$nurl[$k] = trim(str_replace(' ', "%20", $v));
$curl[$k] = curl_init($nurl[$k]);
curl_setopt($curl[$k], CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4 );
curl_setopt($curl[$k], CURLOPT_RETURNTRANSFER, 1);
curl_setopt($curl[$k], CURLOPT_HEADER, 0);
curl_setopt($curl[$k], CURLOPT_CONNECTTIMEOUT, 20);
if(!isset($handle)){
$handle = curl_multi_init();
}
curl_multi_add_handle($handle, $curl[$k]);
}
continue ;
}
$active = null;
do{
$mrc = @curl_multi_exec($handle, $active);
} while ($mrc == CURLM_CALL_MULTI_PERFORM);
while ($active && $mrc == CURLM_OK) {
if (curl_multi_select($handle) != -1) {
do {
$mrc = curl_multi_exec($handle, $active);
} while ($mrc == CURLM_CALL_MULTI_PERFORM);
}
}
foreach ($curl as $k => $v) {
if (curl_error($curl[$k]) == "") {
if ($k == 0) {
$fname[$k] = strtolower($name . '.' . pathinfo($urls[$k], PATHINFO_EXTENSION));
} else {
$fname[$k] = strtolower($name . '_' . $k . '.' . pathinfo($urls[$k], PATHINFO_EXTENSION));
}
$text[$k] = (string) curl_multi_getcontent($curl[$k]);
$filedir[$k] = $dir.'//m.sbmmt.com/m/' . $fname[$k];
if (file_put_contents($filedir[$k], $text[$k])) {
$filepath[$k] = $path . $fname[$k];
}
}
curl_multi_remove_handle($handle, $curl[$k]);
curl_close($curl[$k]);
}
curl_multi_close($handle);
return $filepath;
}
?>