Training, Open Source computer languages
PerlPHPPythonMySQLApache / TomcatTclRubyJavaC and C++LinuxCSS 
Search for:
Home Accessibility Courses Diary The Mouth Forum Resources Site Map About Us Contact
For 2023 (and 2024 ...) - we are now fully retired from IT training.
We have made many, many friends over 25 years of teaching about Python, Tcl, Perl, PHP, Lua, Java, C and C++ - and MySQL, Linux and Solaris/SunOS too. Our training notes are now very much out of date, but due to upward compatability most of our examples remain operational and even relevant ad you are welcome to make us if them "as seen" and at your own risk.

Lisa and I (Graham) now live in what was our training centre in Melksham - happy to meet with former delegates here - but do check ahead before coming round. We are far from inactive - rather, enjoying the times that we are retired but still healthy enough in mind and body to be active!

I am also active in many other area and still look after a lot of web sites - you can find an index ((here))
Deleting a cookie

Posted by admin (Graham Ellis), 19 February 2005
Q: How do I delete a cookie?

A: Set it with an expiry time in the past

There's an example on our web site at

Here's the source code of that page:

$year = 3600*24*365;
if (! is_string($_COOKIE[userkey])) {
       $received = "No cookie received - you are a NEW visitor";
       $newcomer = 1;
       $cval = uniqid("rn:");
       $say = "Your cookie called <b>userkey</b>".
               " will be set to $cval";
} else {
       $received = "Cookie received - you are a RETURNING visitor<br>".
               "Cookie value received - $_COOKIE[userkey]";
       $newcomer = 0;
       if ($_GET[logout]) {
               $newcomer = -1;
               $say = "Your cookie called <b>userkey</b>".
                       " has been deleted";
       } else {
               $say = "Your cookie called <b>userkey</b>".
                       " will NOT be altered";

<title>Setting and clearing a persistant cookie</title>
<body bgcolor="white">
<h2>Setting, reading and deleting a cookie</h2>
When you visit this page for the first time, you'll set a
cookie called <b>userkey</b> to a unique id starting with
"rn:".  The link below to "refresh" the page will visit the
page again, and the link to "logout" will visit the page
again, deleting the cookie.<br><hr><br>
<b>Current status:</b><br><br>
<?= $received ?><br><br><?= $say ?><br><hr><br>
<b>Actions available:</b><br><br>
You may <a href=<?=$PHP_SELF?>>reload this page</a><br>
<?php if ($newcomer != -1) { ?> You may
<a href="<?=$PHP_SELF?>?logout=1">log out</a><br><?php } ?>
You may <a href=/index.html>go to our home page</a><br><hr>
Example written by Graham Ellis of Well House Consultants<br>
We're in the business of training you on subjects like this!<br>
website: <a href=></a>

This page is a thread posted to the opentalk forum at and archived here for reference. To jump to the archive index please follow this link.

You can Add a comment or ranking to this page

© WELL HOUSE CONSULTANTS LTD., 2024: Well House Manor • 48 Spa Road • Melksham, Wiltshire • United Kingdom • SN12 7NY
PH: 01144 1225 708225 • FAX: 01144 1225 793803 • EMAIL: • WEB: • SKYPE: wellho