Hi monks, I am busying myself with cgi-fun and thought it sensible to add in a few safe-guards so that if nothing is entered into the form, the user gets a polite message, not an internal server error. Anyway, I thought this simple reg-exp would work (below). Can anyone suggest why is might be going wrong. Many thanks. 
# snippet from script 1
print qq(<FORM METHOD="post" ACTION="http://localhost/~sm125/cgi-bin/f
+rontpage.cgi"><h3>Enter: </h3><INPUT TYPE="TEXT" NAME="box" SIZE="10"
+><h3>Enter: </h3><INPUT TYPE="text" NAME="value" SIZE="10"><INPUT TYP
+E="SUBMIT" value="go"></FORM>);

[download]
second script 
# snippet from frontpage.cgi
#!/biol/programs/perl/bin/perl -w

use strict;

use CGI qw(:standard);

my $cgi;

$cgi = new CGI;
use CGI::Carp qw(fatalsToBrowser);

my $box = $cgi->param('box');
my $value = $cgi->param('value');


if (($box !~ /\w+/) && ($value !~ /\w+/))   {

 print "You haven't entered anything on the form";
 print STDOUT  $cgi->end_html;
 exit (0);
}

[download]

In reply to CGI + safeguards by Anonymous Monk

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