function ecrire_cookie(nom, valeur) {
  date=new Date;
  date.setMonth(date.getMonth()+6);
  expires = date;
  document.cookie=nom+"="+escape(valeur)+
  ((expires==null) ? "" : ("; expires="+expires.toGMTString()));
}

function getCookieVal(offset) {
var endstr=document.cookie.indexOf (";", offset);
if (endstr==-1)
endstr=document.cookie.length;
return unescape(document.cookie.substring(offset, endstr));
}

function getCookie(name) {
var arg=name+"=";
var alen=arg.length;
var clen=document.cookie.length;
var i=0;
while (i<clen) {
var j=i+alen;
if (document.cookie.substring(i, j)==arg)
return getCookieVal (j);
i=document.cookie.indexOf(" ",i)+1;
if (i==0) break;}
return "";
}