# this is properly placed where perl can find it
use Mymodules::Auth;
use strict;
use warnings;

print "Username: ";
my $username = STDIN;
chomp $username;

ReadMode('noecho');
print "Password: "
my $passwd = STDIN;
chomp($passwd);
ReadMode('restore');

# somehow pass $username and $password to
# Mymodules::Auth and the subroutine auth
# this will return 0 or 1.
my $auth = Mymodules::Auth->auth($username, $passwd);


##</code><code>##

package Mymodules::Auth;
use strict;
use warnings;

sub auth {
   my $username = shift @_;
   my $passwd = shitf @_;

   # here I would use DBI to get the password
   # and username from a database
.
.
.
   if ($db-passwd eq $passwd){
      $auth = 1;
      return $auth;
   }else{
      $auth = 0;
      return $auth;
   }
}
1;