function getCookie(c_name)
{
    if (document.cookie.length>0)
      {
      c_start=document.cookie.indexOf(c_name + "=");
      if (c_start!=-1)
        {
        c_start=c_start + c_name.length+1;
        c_end=document.cookie.indexOf(";",c_start);
        if (c_end==-1) c_end=document.cookie.length;
        return unescape(document.cookie.substring(c_start,c_end));
        }
      }
    return "";
}

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

function checkCookie()
{
    username=getCookie('selected_');
    if (username!=null && username!="")
      {
      alert('Welcome again '+username+'!');
      }
    else
      {
      username=prompt('Please enter your name:',"");
      if (username!=null && username!="")
        {
        setCookie('username',username,365);
        }
      }
}

function createCookie(name,value,days) {
	if (days) {
		var date = new Date();
		date.setTime(date.getTime()+(days*24*60*60*1000));
		var expires = "; expires="+date.toGMTString();
	}
	else var expires = "";
	document.cookie = name+"="+value+expires+"; path=/";
}

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 readAllCookie() {
	var ca = document.cookie.split(';');
	return ca;
}

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