input type="file" - temp files deleted with post-redirect-get

Question

I have a form where I allow the user to upload files. I just changed the post processing to a post-redirect-get since the user enters other information as well. I noticed that the global $_FILE is visible to the redirect.php but is lost after redirecting back to the input form. I attempted to save the $_FILE array, but it appears that the temp files are removed with the post-redirect-get. Is there any way to tell the server to preserve the temp files when leaving the redirect.php so I can process them when I see fit? Thanks in advance.

User Form:

<input type="file" name="file[]" id="userfiles" size='1px' multiple onChange="makeFileList();" />

Redirect File:

if (isset($_FILES)){
    $_SESSION['post-files'] = $_FILES;
}
header("Location: /back/to/input/form.php");

Answer 1

In the end, the simplist solution was to process the temp files in the redirect.php and store the files in my own temp location. I then can deal with them once back in my processing form. For anyone who follows, this is what I did...

if (isset($_FILES)){
  $_SESSION['post-files'] = $_FILES;
  $i=0;
  foreach ($_SESSION['post-files']['file']['name'] as $filename){
    // get the file to upload
    $fromfile=$_SESSION['post-files']['file']['tmp_name'][$i];

    // get just the filename
    $filename = pathinfo($fromfile, PATHINFO_FILENAME) . '.' . pathinfo ($fromfile, PATHINFO_EXTENSION);

    // give it a new path
    $tofile = "/some/temp/path/". $filename;

    // store the new temp location
    $_SESSION['post-files']['file']['tmp_name'][$i] = $tofile;

    // move the files to a temp location
    if (!is_dir(pathinfo($tofile,PATHINFO_DIRNAME))) {
        mkdir(pathinfo($tofile,PATHINFO_DIRNAME), 0777, true);
    }
    move_uploaded_file($fromfile,$tofile);
  }
}

Answer 2

You might be able to pass an encoded copy of the file(s) into the session.

Something like...

$tempImages = array();

foreach($_FILES as $file)
{
    $tempImages[] = base64_encode(file_get_contents($file['tmp_name']));
}

$_SESSION['post-files'] = serialize($tempImages);