function readCookie(name) {
	var nameEQ = name + "=";
	var ca = document.cookie.split(';');
	for(var i=0;i < ca.length;i++) {
		var c = ca[i];
		while (c.charAt(0)==' ') c = c.substring(1,c.length);
		if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
	}
	return null;
}

function setCookie(c_name,value,exdays)
{
	var exdate=new Date();
	exdate.setDate(exdate.getDate() + exdays);
	var c_value=escape(value) + ((exdays==null) ? "" : "; expires="+exdate.toUTCString());	
	document.cookie=c_name + "=" + c_value;
}

function eraseCookie(name) {
	createCookie(name,"",-1);
}