If you want to be interactive with the user and accept user input, all you need to do is read from stdin.
<?php
echo "Are you sure you want to do this? Type 'yes' to continue: ";
$handle = fopen ("php://stdin","r");
$line = fgets($handle);
if(trim($line) != 'yes'){
echo "ABORTING!\n";
exit;
}
echo "\n";
echo "Thank you, continuing...\n";
?>
