What is the significance of this code in index.php in phpcms?

<code>if (strpos($_SERVER["REQUEST_URI"], "/CHA")===0 ) {
    $end = strpos($_SERVER["REQUEST_URI"], "/", 1);
    $channel = substr($_SERVER["REQUEST_URI"], 1, $end-1);
    $channelConfig = pc_base::load_config('channel');
    if ( !empty($channel) && isset($channelConfig[$channel]) ) {
        setcookie("channel", $channel, time()+7*86400, "/");
    }
}

</code>

I understand the meaning of this code in index.php in phpcms, but I don’t know what it means. Is it generally like this in phpcms?

Reply content:

<code>if (strpos($_SERVER["REQUEST_URI"], "/CHA")===0 ) {
    $end = strpos($_SERVER["REQUEST_URI"], "/", 1);
    $channel = substr($_SERVER["REQUEST_URI"], 1, $end-1);
    $channelConfig = pc_base::load_config('channel');
    if ( !empty($channel) && isset($channelConfig[$channel]) ) {
        setcookie("channel", $channel, time()+7*86400, "/");
    }
}

</code>

I understand the meaning of this code in index.php in phpcms, but I don’t know what it means. Is it generally like this in phpcms?