Sessions and varaibles

[jbn]

my friend is coding a database and has some problems
with sessions/session id's etc.. can anyone write some examples
how to make this work with sessions?

[WiZARD]

<?
unset($s);
session_start();
session_register("s");
if (isset($c) && $c=='clear') {
unset($s);
header("Location: sess.phtml");
echo "clear...";
exit;
}

echo "<a href=sess.phtml>Reload</a><p>";
echo "<a href=sess.phtml?c=clear>Clear</a><p>";

if (!isset($s['count'])) {
$s['count']=1;
}
else $s['count']++;
echo "You are loaded this page: $s[count]<p>";

if (strlen($name)>1) $s['name']=$name;

if (!isset($s['name']))
echo "You are new user. Type your name please:
<form action=sess.phtml><input type=text name=name>
<input type=submit></form>";
else
echo "You registered: $s[name]";
?>

[WiZARD]

<?
// Before use this script create tmp directory

session_id("0123456789abcdef0123456789abcdef");
session_start();
session_register("flag");
if (!isset($flag)) $flag=0;

switch ($c) {

case "":

echo "FLAG=$flag <a href=$PHP_SELF?c=clear>Clear</a>
<form action=$PHP_SELF>
<input type=hidden name=c value='submit'>
<input type=submit>
</form>";

break;

case "clear":

$flag=0;
header("Location: $PHP_SELF");

break;

case "submit":

if ($flag==0) {

sleep(5);
$flag=1;

srand ((double) microtime() * 1000000);
$filename= "tmp/".rand(0,9999).".php-test";
fclose(fopen($filename,"w+"));

header("Location: $PHP_SELF");

}
else
echo "FLAG is not zero.";
break;
}
?>