How can PHP work in conjunction with htaccess to secure file access on a server?

To secure file access on a server using PHP and htaccess, you can use htaccess to restrict direct access to certain files or directories, and then use PHP to authenticate users before allowing access to those files. This combination helps to add an extra layer of security to your server by controlling who can access specific files.

<?php
// Check if the user is authenticated before allowing access
session_start();

if (!isset($_SESSION['authenticated']) || $_SESSION['authenticated'] !== true) {
    header('HTTP/1.1 401 Unauthorized');
    exit;
}

// If user is authenticated, allow access to the file
// Your file processing code here
?>