#!/usr/bin/perl
use strict;
use warnings;
use CGI;

# unbuffer output
$|++;

print $q->header().
      $q->start_html.
      $q->start_form({-name=>'statusform'}).
      $q->textfield('status','',50,50).
      $q->end_form;

for (0..100) {
    print_status("$_\% completed");
    sleep(1);
}

print $q->end_html;
exit(0);

sub print_status {
    my $status = $_[0];
    $status =~ s/'/\\'/g;
    print $q->script({-language=>'javascript'},
              "document.statusform.status.value = '$status'\n"
          );
}