Site gets unresponsive after file download. What d

问题:

I have the code below that i use to download a file from the HDD. The problem I get is that if I stop a download in the middle or after the download ends, the site becomes unresponsive. Any idea why? The environment is LAMP.

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// get mime type
if ($dwld_allowed_ext[$fext] == '') {
    $mtype = '';
    // mime type is not set, get from server settings
    if ($file_type == null) {
        if (function_exists('mime_content_type')) {
            $mtype = mime_content_type($file_path);
        }
        else if (function_exists('finfo_file')) {
            $finfo = finfo_open(FILEINFO_MIME); // return mime type
            $mtype = finfo_file($finfo, $file_path);
            finfo_close($finfo);
        }
    }
    else {
        $mtype = $file_type;
    }
    if ($mtype == '') {
        $mtype = "application/force-download";
    }
}
else {
    // get mime type defined by admin
    $mtype = $dwld_allowed_ext[$fext];
}

$asfname = $fname;

// set headers
header("Pragma: public");
header("Expires: 0");
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
header("Cache-Control: public");
header("Content-Description: File Transfer");
header("Content-Type: $mtype");
header("Content-Disposition: attachment; filename=\"$asfname\"");
header("Content-Transfer-Encoding: binary");
header("Content-Length: " . $fsize);

// download
// @readfile($file_path);
$file = @fopen($file_path,"rb");
if ($file) {
    while(!feof($file)) {
        print(fread($file, 1024*8));
        flush();
        if (connection_status()!=0) {
            @fclose($file);
            die();
        }
    }
    @fclose($file);
}

回答1:

Call session_write_close() right before sending any download headers.

See this comment:

It might be worth noting that if your site uses a front controller with sessions and you send a large file to a user; you should end the session just before sending the file, otherwise the user will not be able to continue continue browsing the site while the file is downloading.

回答2:

Does it become totally unresponsive? Unaccessible to other users? other browsers? I ask because I have a couple of sites where stopping a large page load will hang FireFox for a long time. Other browsers (on the same computer) and other users can still access the site fine. Apparently, in my case, FF is hung but the site is ok.

Edit: After reading your code, it seems a little fishy that your file close command is inside a while loop checking for eof. Try the readfile command to replace that whole file reading thing you're doing: http://us2.php.net/manual/en/function.readfile.php

回答3:

Try adding exit(); after you print the file (after the last } in the snipped provided). This will stop PHP from parsing the rest of your code which is one reason why you may have the problems you are describing.