通过PHP启动.php脚本异步并回答请求

I try to start a .php script asynchron from an other php script.

if (substr(php_uname(), 0, 7) == "Windows"){
    $cmd = "start /B php AsynchronDownload.php fileids=".$this->header->queryParams['ids'] . " uid=".$this->header->tokenData->uId . " groupId=".$this->header->tokenData->groupId . " timestamp=".$this->header->tokenData->timestamp . " state=".$this->header->tokenData->state. " token=".$this->header->tokenData->token;
    pclose(popen($cmd, "r")); 
} else {
    $cmd = "/usr/bin/php7.2-cli AsynchronDownload.php fileids=".$this->header->queryParams['ids'] . " uid=".$this->header->tokenData->uId . " groupId=".$this->header->tokenData->groupId . " timestamp=".$this->header->tokenData->timestamp . " state=".$this->header->tokenData->state. " token=".$this->header->tokenData->token;
    exec($cmd . " > /dev/null &");
}

Thats work fine. But is it possible to awnser to an Http Request, how is send to the first skript from a client in the second asynchron started skript? I found out the details about the Request are not available on the second skript.

If I try to set Headers for the Response with (for example) header('Content-type: x-zip') they are not set. headers_list() funktion returning NULL.