loading local file synchronically using WWW?

I was wondering if the WWW can be used without yield when loading the local files?

I have tried to use it to load local file synchronically:

WWW www = new WWW( "file:///" + assetPath );
AssetBundle prefabBundle = www.assetBundle;
GameObject instance = (GameObject)Instantiate( prefabBundle.Load( prefabName ) );

It works but I am not sure whether it is due to the file size is small.

Thanks!

while (!www.IsDone)
{
// sychnonuous wait
}

just use System.IO.File.ReadAllText