Read value in field 'fileUpload'

Hello! I want to get value from <hbj:fileUpload> in javascript.

I can do that using simple <hbj:inputField> like this:

<sscript language="javascript">
	var funcName = htmlb_formid+"_getHtmlbElementId";
	var func = window[funcName];
	var myField = eval(func('FieldField'));
	var sOpen = sStatus.getValue();
</sscript>

How can I do something like this whith <hbj:fileUpload>?

When user select file from local machine I want to determine it's absolute path inside javascript. Problem that hbj:fileUpload have no property jsObjectNeeded="true"...