Hi monks, I read the CGI.pm: 'http://search.cpan.org/~lds/CGI.pm-3.43/CGI.pm#USING_THE_FUNCTION-ORIENTED_INTERFACE', and then try to use function-oriented interface to run the cgi example as the manual shows: 
   use CGI qw/:standard/;
   print 
       header,
       start_html('Simple Script'),
       h1('Simple Script'),
       start_form,
       "What's your name? ",textfield('name'),p,
       "What's the combination?",
       checkbox_group(-name=>'words',
                      -values=>['eenie','meenie','minie','moe'],
                      -defaults=>['eenie','moe']),p,
       "What's your favorite color?",
       popup_menu(-name=>'color',
                  -values=>['red','green','blue','chartreuse']),p,
       submit,
       end_form,
       hr,"\n";

    if (param) {
       print 
           "Your name is ",em(param('name')),p,
           "The keywords are: ",em(join(", ",param('words'))),p,
           "Your favorite color is ",em(param('color')),".\n";
    }
    print end_html;

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Yes, the cgi scripts run well and show the expected result, however, I see a lot of warnings at 'error.log': 
root@Sparta:/var/www/cgi-bin# tail -f /var/log/apache2/error.log
CGI::param called in list context from /var/www/cgi-bin/test.cgi line 
+22, this can lead to vulnerabilities. See the warning in "Fetching th
+e value or values of a single named parameter" at /usr/local/share/pe
+rl/5.18.2/CGI.pm line 404.

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I used object-oriented style before, and this is my first experience to function-oriented style. I googled for this question and just found the items according to 'object-oriented style'. Would you please help me explain the warning message at log? and how to fix it as function-oriented style? Thanks, PH

In reply to CGI problem: USING THE FUNCTION-ORIENTED INTERFACE by PhillipHuang

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