php - URL への iPhone 画像のアップロード。upload_tmp_dir が空です

Question

多くの人がここで同様の質問をしていることは知っていますが、どういうわけかまだうまくいきません。簡単にするために、以前にロードしたUIImageをobjectiveCに（C4フレームワークを使用して）次のように保存しようとしています：

-(void)setup {
    UIImage *myImage=[UIImage imageNamed:@"image.jpg"];

    NSData *imageData = UIImageJPEGRepresentation(myImage, 1.0);
    // setting up the URL to post to
    NSString *urlString = @"my full server address/imageupload.php";

    NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
    [request setURL:[NSURL URLWithString:urlString]];
    [request setHTTPMethod:@"POST"];

    NSString *boundary = @"---------------------------14737809831466499882746641449";
    NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary];
    [request addValue:contentType forHTTPHeaderField: @"Content-Type"];

    NSMutableData *body = [NSMutableData data];
    [body appendData:[[NSString stringWithFormat:@"\r\n--%@\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];

    [body appendData:[@"Content-Disposition: form-data; name=\"userfile\"; filename=\"dr.jpg\"\r\n" dataUsingEncoding:NSUTF8StringEncoding]];

    [body appendData:[@"Content-Type: application/octet-stream\r\n\r\n" dataUsingEncoding:NSUTF8StringEncoding]];
    [body appendData:[NSData dataWithData:imageData]];
    [body appendData:[[NSString stringWithFormat:@"\r\n--%@--\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    // setting the body of the post to the reqeust
    [request setHTTPBody:body];

    // now lets make the connection to the web
    NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
    NSString *returnString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];

    C4Log(@"returnString: %@", returnString);

}

そして、私の upload.php は次のようになります。

<?php
      $uploaddir = './'; //Uploading to same directory as PHP file
      $file = basename($_FILES['userfile']['name']);
      $uploadFile = $file;
      $randomNumber = rand(0, 99999); 

      $newName = $uploadDir . $uploadFile;

    if (is_uploaded_file($_FILES['userfile']['tmp_name'])) {
   echo "Temp file uploaded. \r\n ";
    } else {
    echo "Temp file not uploaded. \r\n";
   }
   move_uploaded_file($_FILES['userfile']['tmp_name'], $newName);

         $postsize = ini_get('post_max_size'); 
         $canupload = ini_get('file_uploads');  
         $tempdir = ini_get('upload_tmp_dir'); 
         $maxsize = ini_get('upload_max_filesize');
         echo "http://mlab.taik.fi/UrbanAlphabets/{$file}" . "\r\nsize:" .  $_FILES['userfile']['size'] . "\r\ntype:" . $_FILES['userfile']['type']. "\r\npostsize:" . $postsize."\r\ncanupload:" . $canupload ."\r\ntempdir:" .$tempdir."\r\nmaxsize:".$maxsize;

?>

何らかの理由で「upload_tmp_dir」が空のように見えますが、修正方法がわかりません...エコーは次のとおりです。

Temp file uploaded. 

 MY SERVER/dr.jpg

size:31476

type:application/octet-stream

postsize:100M

canupload:1

tempdir:

maxsize:100M

ヒントはありますか？