Streaming Large Files with PHP Script

Using a similar script found in the comments of http://php.net/manual/en/function.fread.php, I've devised this function:

function readfile_chunked_remote($filename, $seek = 0, $retbytes = true, $timeout = 3) {
    set_time_limit(0);
    $defaultchunksize = 1024*1024;
    $chunksize = $defaultchunksize;
    $buffer = '';
    $cnt = 0;
    $remotereadfile = false;

    if (preg_match('/[a-zA-Z]+:\/\//', $filename))
        $remotereadfile = true;

    $handle = @fopen($filename, 'rb');

    if ($handle === false) {
        return false;
    }

    header("Content-Type: application/octet-stream; ");
    header("Content-Transfer-Encoding: binary");
    header("Cache-Control: no-cache, must-revalidate");
    header("Content-Length: " . filesize($filename));
 开发者_JAVA百科   header("Content-Disposition: attachment; filename=\"" . basename($filename) . "\"");

    stream_set_timeout($handle, $timeout);

    if ($seek != 0 && !$remotereadfile)
        fseek($handle, $seek);

    while (!feof($handle)) {

        if ($remotereadfile && $seek != 0 && $cnt+$chunksize > $seek)
            $chunksize = $seek-$cnt;
        else
            $chunksize = $defaultchunksize;

        $buffer = @fread($handle, $chunksize);

        if ($retbytes || ($remotereadfile && $seek != 0)) {
            $cnt += strlen($buffer);
        }

        if (!$remotereadfile || ($remotereadfile && $cnt > $seek))
            echo $buffer;

        ob_flush();
        flush();
    }

    $info = stream_get_meta_data($handle);

    $status = fclose($handle);

    if ($info['timed_out'])
        return false;

    if ($retbytes && $status) {
        return $cnt;
    }

    return $status;
}

However, it seems to still time out for files over 100mb or so... where might I be going wrong?

Try xmoovstream. It will do it for you. Opensource as well.

According to the manual, use readfile()

Note: readfile() will not present any memory issues, even when sending large files, on its own. If you encounter an out of memory error ensure that output buffering is off with ob_get_level().

http://php.net/readfile