I solved the problem.
There was a problem with JavaScript.

Now it works perfectly:
#!/usr/bin/perl -w

use strict;
use warnings;
use CGI;
my $query = new CGI;
use CGI::Carp qw(fatalsToBrowser);

$|=1;
print $query->header;
print "<html>\n";
print "<head>\n";
print "<title>ntop startup script</title>\n";
print "<STYLE TYPE='text/css'>\n";
print "h3 { color: red }\n";
print "a { text-decoration: none; font: bold 14pt/16pt Ariel, serif }"
+;
print "a:hover { color: red } /* when mouse is over link */";
print "</style>\n";
    print "<SCRIPT LANGUAGE = \"JavaScript\">\n";
    print "<!-- \n";
    print "function hideWaitMsg(){
           document.getElementById('wait_msg_text').style.visibility =
+ 'hidden'; }\n";
    print "// -->\n";
    print "</SCRIPT>\n";
print "</head>\n";
print "<center>";
print "<body bgcolor=\"#c0c0d0\" onLoad=\"hideWaitMsg()\"><br>\n";
print "<div id=\"wait_msg_text\">pls wait, ntop will be started !</div
+> \n";
print "<p><br></p>";

system `/usr/local/www/cgi-bin/ntop/ntop.sh stop` or die "cannot stop 
+ntop: $!";
sleep(8);
my $cc = `sudo /usr/local/www/cgi-bin/ntop/ntop.sh start` or die "cann
+ot start ntop: $!";
print "<font face=\"arial,helvetica\" size=2 color=\"#006600\">status:
+</font> ",$cc,"<br><br>\n";

print "<font face=\"arial,helvetica\" size=2 color=\"#FF0000\">
pls do not forget to shutdown, if you're not using </font> \n";
print "\n";
print "<p><br></p>";
print "pls wait for 5 seconds before you click on this link:\n";
print "<br><br>";
print "<a href=\"https://192.168.0.3:3001\"><b><U>NTOP</b></U></a>\n";
print "<p><br></p>";
print "<p><br></p>";
print "<p><br></p>";
print "Maintained by <a href=\"mailto:admin@\domain.net\"><font face=\
+"arial,helvetica\" size=3>
admin</a></font>\n";
print "</center>";
print "</body>";
print "</html>";

exit($cc);

[download]

greetings
cc

In reply to Re^10: show a message only during the sleep time by cc
in thread show a message only during the sleep time by cc

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