Your code does not compile, and your question is unclear.

I have attempted to correct it - and this code should get you the expected "submit=a1" in the querystring on hitting "submit".

Also - naming your sub "header" in a CGI program is a bad idea. I changed it to MyHeader. 

uuse strict;
use warnings;
use DBI;
use Getopt::Long;
use CGI qw/:all :cgi-lib/;
my  $CGI_params = Vars();
my %CGI_PARAM  = %$CGI_params;
my $site = "";
my $site_selected="a1";
$site = "a1";
$site_selected = $CGI_PARAM{'popup'};
$site = $CGI_PARAM{'popup'};

if($site_selected =~ /^\s*$/) {
    $site = "a1";
    $site_selected="a1";
}
defined $site or die "usage:$0";
my %map=(a1=>[qw(r_a1_c)],a1=>[qw(r_a2_c)],);
show();
sub show{
  status();
  MyHeader();
}
sub status{
my $stm=$site_selected;
}
sub MyHeader
{
print start_form(-method=>"GET",-action=>"db.cgi");
print " <br> &nbsp<B>Site</B> &nbsp";
print popup_menu(
       -name    => 'popup',
       -value  =>  keys % map,
       -default => 'value2'
         );

print "&nbsp &nbsp &nbsp &nbsp &nbsp";
print submit(-type=>"submit",-name=>"submit",-value=>$site);
print end_form, "\n";
}

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        ...it is unhealthy to remain near things that are in the process of blowing up.     man page for WARP, by Larry Wall

In reply to Re: Attribute values are not passed into the variable using perl cgi? by NetWallah
in thread Attribute values are not passed into the variable using perl cgi? by gpssana

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