The code mentioned below is the working example of PHP flush in IIS.
<?php
header("Content-Type: text/html; charset=utf-8");
function flush_buffers(){
ob_end_flush();
ob_flush();
flush();
ob_start();
}
ob_start();
flush_buffers();
echo "starting...<br/>\n";
for($i = 0; $i < 60; $i++) {
flush_buffers();
print "$i<br/>\n";
flush_buffers();
sleep(2);
}
flush_buffers();
print "DONE!<br/>\n";
?>
