Use of uninitialized value $domain in string ne at dnsdig.cgi line 9.
Use of uninitialized value $domain in concatenation (.) or string at d
+nsdig.cgi line 18.
Can't call method "answer" on an undefined value at dnsdig.cgi line 19
+.
[download]

#!/usr/bin/perl -w

use strict;
use Net::DNS;
my $dns = new Net::DNS::Resolver;

my $domain;

if($domain ne "") {
print "<form action=\"dnsdig.cgi\" method=\"post\">
<input name=\"domain\" type=\"text\" value=\"\" />
<input type=\"submit\" value=\"Get MX\" />
</form>";
} else {
    my $mx = $dns->query( $domain, 'MX' );

print "content-type:text/html; charset=utf-8\n\n";
    print "$domain:\n\n";
    foreach my $rr ($mx->answer) {
        print "<br />", $rr->exchange, ' [<b>', $rr->preference, "</b>
+]\n";
    }
}
[download]

#!/usr/bin/perl -Tw
use perl::always;
my $perl_version = "5.12.4";
print $perl_version;

Ok, now the error message looks differently, don't you agree? :)

$domain is already defined, but uninitialized. Please replace my $domain; with my $domain = 'google.com'; and check the result.

Yes, I agree. :)
Just tried this:


#!/usr/bin/perl -w

use strict;
use Net::DNS;
my $dns = new Net::DNS::Resolver;

my $domain;

if($domain ne "") {
    my $mx = $dns->query( $domain, 'MX' );

print "content-type:text/html; charset=utf-8\n\n";
    print "$domain:\n\n";
    foreach my $rr ($mx->answer) {
        print "<br />", $rr->exchange, ' [<b>', $rr->preference, "</b>
+]\n";
    }
} else {
print "content-type:text/html; charset=utf-8\n\n";
print "<form action=\"dnsdig.cgi\" method=\"post\">
<input name=\"domain\" type=\"text\" value=\"\" />
<input type=\"submit\" value=\"Get MX\" />
</form>";
}
[download]

But again, fail:


Use of uninitialized value $domain in string ne at dnsdig.cgi line 9.
Use of uninitialized value $domain in string ne at dnsdig.cgi line 9.,
+ referer: ...
[download]

Now I'll use your newest recommendation (which I know will work), but doesn't provide the empty form field I'm looking for -- but I'll do it anyway. :)
--Chris

#!/usr/bin/perl -Tw
use perl::always;
my $perl_version = "5.12.4";
print $perl_version;

D'OH!
That should have read:
if($domain eq "") {
not
if($domain ne "") {
Sorry.
It still doesn't work.
--Chris

#!/usr/bin/perl -Tw
use perl::always;
my $perl_version = "5.12.4";
print $perl_version;