PHP : rename() How do I find the error cause?

Question

I would like to print out the cause of the error.

error_get_last() doesn't seem to return anything. rename() returns TRUE|FALSE rather than an exception.

if (!rename($file->filepath, $full_path)) {
  $error = error_get_last();
  watchdog('name', "Failed to move the uploaded file from %source to   %dest", array('%source' => $file->filepath, '%dest' => $full_path));
}

Answer 1

First, it's a better practice to add some safety checks before:

if (file_exists($old_name) && 
    ((!file_exists($new_name)) || is_writable($new_name))) {
    rename($old_name, $new_name);
}

Second, you can turn on error reporting:

error_reporting(E_ERROR | E_WARNING | E_PARSE | E_NOTICE);