How can PHP scripts handle long processing times while keeping the client informed?

When PHP scripts have long processing times, it can lead to timeouts or the client thinking the script has failed. To keep the client informed, you can use techniques like output buffering, AJAX requests, or server-sent events to provide updates on the progress of the script.

<?php

ob_start();

// Long processing code here

// Send updates to the client
echo "Processing step 1 completed.";
ob_flush();
flush();

// More processing code

// Send final result to the client
echo "Processing completed.";

ob_end_flush();
?>