Consider this code:

#!/usr/bin/perl -w

$|++;

use CGI;

$q = new CGI;

print $q->header(), $q->start_html(), "before wait<br /><br/>";

sleep 5;

print "after wait\n\n\n", $q->end_html;
[download]

As shown, my browser (Mozilla 1.4) renders "before wait", then several seconds later, "after wait" appears.

If I comment out the $|++; then all of it shows up in the browser at the same time.

--Bob Niederman, http://bob-n.com

All code given here is UNTESTED unless otherwise stated.