How can PHP developers prevent "Header already sent" errors when working with session_start()?

When working with session_start() in PHP, developers can prevent "Header already sent" errors by ensuring that there is no whitespace or output before the session_start() function is called. This error occurs when PHP tries to send HTTP headers after output has already been sent to the browser, which can happen if there is whitespace or HTML content before session_start(). 

<?php
ob_start(); // Start output buffering
session_start(); // Start the session

// Rest of your PHP code goes here

ob_end_flush(); // Flush output buffer
?>

Keywords

session_start output buffering ob_start headers_sent error_reporting

Related Questions