session variables lost unexpectedly

[xxoulmate]

why there's an instance.
my page been session timeout.

code something like this:

//login page
session_start();
$_SESSION['var1'] = "username";
//will be redirected to main.php when logged in
header('location:main.php');

//main.php
session_start();
echo session_id();
foreach($_SESSION as $key=>$value)
{
echo $key." = ".$value."<br>";
}

when i refresh the page of main.php
sometime i get no session.
something like all my session variables been gone.
but the sessionid still the same.
my script didnt unset or use session_destroy ()
therefore it must be there.

[dlite922]

You might be sending the header due to content in your PHP file before session start.

Make sure the first character in your PHP file is <?php. No spaces or anything else. Those should be on the first line, first character of the file. And make sure you immediately call session_start() without echoing or doing anything else.

Let me know if that worked or not.

[xxoulmate]

session start is at the begginning of the script.
and there is no space either on the first line.

is it something to do with what they call garbage collector.

[Dormilich]

and there is no space either on the first line.

you may not always see the characters, ref. http://bytes.com/topic/php/insights/...s-already-sent

on the other hand side, if there were indeed whitespace, it would have triggered a warning.

is it something to do with what they call garbage collector.

that would depend on your session settings in php.ini

[xxoulmate]

yep it was., it will trigger warning of character already established.,

my system has a an option of session length: forever
but theres' a time (no definite time). all session variables gone. so my system logout the user. That's really the problem.