Warning: session_destroy(): Trying to destroy uninitialized session

Question

my class.inc file:

<?php
class logout{
    public function logout(){
        $_SESSION = array();
        if (ini_get("session.use_cookies")) {
            $params = session_get_cookie_params();
            setcookie(session_name(), '', time() - 42000, $params['path'], $params['domain'], $params['secure'], $params["httponly"]);
        }
        session_destroy();
    }   
}

?>

used code for my logout:

session_start();
require($path."include/class.inc");
if(!empty($_GET['logout'])){
    $object=new logout();
    $object->logout();
    $content='5;url='.$path.'index.php';
}

When the logout function is called, it destroys the session, but shows the warning:

Warning: session_destroy(): Trying to destroy uninitialized session in class.inc on line 9

I am unable to troubleshoot, as the session is not being destroyed by any other means before the session_destroy() of class.inc.

This error warning comes when there is not any session started. — Rohit Choudhary, Aug 12 '13 at 13:53
i'm starting the session in each page at the top just after ` — RatDon, Aug 12 '13 at 13:54
@TobiasKun my logout is on same page only. it's inside a head.inc file which is included in every page. — RatDon, Aug 12 '13 at 14:05

score 44 · Accepted Answer · edited Jan 20 '17 at 10:53

44

You have to call the function mentioned below at the top your logout function in the logout class.

session_start();

Add the above function and try it out. If you don’t start the session at the top of your file, it will throw exceptions like “headers already sent”, “can’t start the session”, etc.

edited Jan 20 '17 at 10:53

TRiG

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answered Aug 12 '13 at 13:59

Jijo John

1,375
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1

though i'm including the class file in a page where the session already started... i've to use `session_start()` in every class the session is being used. else it's throwing an error. – RatDon Jan 31 '14 at 06:08

score 15 · Answer 2 · answered Aug 12 '13 at 13:56

15

This error is common when you haven't started the session beforehand

if (!isset($_SESSION))
  {
    session_start();
  }

answered Aug 12 '13 at 13:56

James

4,644
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@Jonathan you may try `if(!session_id()) session_start();` – AboElnouR Sep 10 '18 at 13:24

score 5 · Answer 3 · answered Jan 29 '21 at 17:13

5

https://www.php.net/manual/en/function.session-status.php

if (session_status() === PHP_SESSION_ACTIVE)
        session_destroy();

answered Jan 29 '21 at 17:13

scr4bble

192
1
15

score 2 · Answer 4 · answered Jul 22 '14 at 21:06

I encountered the session_destroy() error message when I started using session_write_close(). To determine if session_destroy() should be called or not, I had to do the following:

class Session {
    public static function start() {
        self::$haveSession = true;
        session_start();
    }
    public static function finish() {
        session_write_close();
        self::$haveSession = false;
    }
    public static function clear() {
        if (self::$haveSession) {
            session_unset();
            session_destroy();
        }
    }
}

In PHP >= 5.4 it should work to replace if (self::$haveSession) with if(session_status() === PHP_SESSION_ACTIVE).

score 1 · Answer 5 · answered Sep 11 '18 at 22:21

1

You can add this code to start a session if it didn't start before

if(!session_id()) {
    session_start();
}

answered Sep 11 '18 at 22:21

AboElnouR

281
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14

Padmanathan J · Answer 6 · 2013-08-12T13:59:07.943

0

Start your session session_start(); and you can destroy your session

    <?php
    session_start();
    class logout{
        public function logout(){
            $_SESSION = array();
            if (ini_get("session.use_cookies")) {
                $params = session_get_cookie_params();
                setcookie(session_name(), '', time() - 42000, $params['path'], $params['domain'], $params['secure'], $params["httponly"]);
            }
            session_destroy();
        }   
    }

?>

edited Aug 12 '13 at 13:59

answered Aug 12 '13 at 13:53

Padmanathan J

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remove `@` from `@session_destroy();` it'll show the warning. – RatDon Aug 12 '13 at 13:58
1

it's not correct man. it's showing another notice `Notice: A session had already been started - ignoring session_start() in class.inc on line 2` as the file is included in each file after `session_start();`. so two `session_start();` will show a notice. – RatDon Aug 12 '13 at 14:07

score 0 · Answer 7 · answered May 05 '14 at 10:18

You'll have to call session_start() before you call session_destroy();

Are you storing session in data in files or in a database. If you are storing it in a database, I normally just delete the record from the session table that corresponds to the session id, that way you don't have to unregister each session var and it actually deletes the whole session.

Warning: session_destroy(): Trying to destroy uninitialized session

7 Answers7

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