android中的php响应字符串

I am writing a simple app to send text files to server. The code works fine, but the response from server is "OK". In the php code (I found online), the return string should be "success". Please suggest what I am doing wrong. The server response is:

I/uploadFile(11338): HTTP Response is : OK: 200

but I want something like:

I/uploadFile(11338): HTTP Response is : success: 200

in android for printing, I use:

               serverResponseCode = conn.getResponseCode();
               String serverResponseMessage = conn.getResponseMessage();  
               Log.i("uploadFile", "HTTP Response is : "
                       + serverResponseMessage + ": " + serverResponseCode);

where as php looks like:

<?php

    $file_path = "/var/www/html/Extract/";

    $file_path = $file_path . basename( $_FILES['uploaded_file']['name']);
    if(move_uploaded_file($_FILES['uploaded_file']['tmp_name'], $file_path)) {
        echo "success";
    } else{
        echo "fail";
    }
 ?>

As per http://php.net/manual/en/function.header.php

header('HTTP/1.0 200 success');