Need a simple function to store/get a variable/element value to/from a cookie

Need a simple function to store/get a variable/element value to/from a cookie

Hi,
 
I have a jquiry/javascript the first line of which is :
 
document.writeln('<div class="dc-rnav"><a href="javascript:history.go(-1)" title="Go Back">Go Back</a> | <a href="login.pl" title="This will log you out">Log out</a> | <a href="" title="" >$user</a></div>');
 
 
You would have spoted $user which does not fit there, therefore what I would like to do is to add a function to this scrip which which will  get the user name from the cookie as long as the session last.
 
I believe it will be done in two parts, initially when a user logs in, the $user value will be passed to a javascript from within the html through perl script like :
 
my $user  = $q->param('user');
$user = "JAKE";
........
then the javascript function or whatever which will read the $user variable and save it to a cookie under <script> tag within html like :
 
<script>
document.cookie =
  'ppkcookie=logincookie; user=$user path=/'
 
</script>
 
 
Then the function which will read the $user value from cookie which will be in the script I mentioned above which will be called throughout my application so I don't have to pass the $user value around to each and every script within my application. 
 
function readCookie(name) {
    get the user name from the cookie
    pass it to the following line :
    document.writeln('<div class="dc-rnav"><a href="javascript:history.go(-1)" title="Go Back">Go Back</a> | <a href="login.pl" title="This will log you out">Log out</a> | <a href="" title="" >$user</a></div>');
}
 
I apologize for my English which is not upto the standard. But I hope I have made my point clear.
 
Many thanks for your help !!
Tonya