How to Avoid \"Notice: A session had already been started - ignoring session_start()\" in PHP?

PHP Session Initiation and Avoidance of Duplicate Session Starts

In PHP, you may encounter a scenario where attempting to initiate a new session after a session has already commenced leads to a notice: "Notice: A session had already been started - ignoring session_start()." This notice indicates that your code is trying to start a new session when one has already been established.

To avoid this issue, you can employ a conditional check to determine if a session has already been initialized. If no session is found, then you can safely initiate a new session.

Here's a code snippet demonstrating this approach:

<code class="php"><?php
    if(!isset($_SESSION)) 
    { 
        session_start(); 
    } 
?></code>

In this code, the isset($_SESSION) check ensures that a session has not yet been initialized. If this is the case, the session_start() function is invoked to create and initialize a new session.

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