What steps can be taken to troubleshoot and resolve the "headers already sent" warning in PHP code to ensure proper functionality?

The "headers already sent" warning in PHP code occurs when output is sent to the browser before headers are set, which can cause issues with functions like header() or setcookie(). To resolve this, ensure that no whitespace or output is sent before calling header() or setcookie(), and make sure to place these functions before any HTML or output. 

<?php
ob_start(); // Start output buffering

// Your PHP code here

ob_end_flush(); // Flush the output buffer
?>

Keywords

output buffering ob_start ob_clean header error_reporting

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