$id = $query->cookie(-name=>"SESSID");
eval {
    tie %session, 'Apache::Session::File', $id,
        { Directory => "$cartInfoPath",
          LockDirectory => "$cartInfoPath"};
};

if ($@) {
    if ($@ =~ /^Object does not exist in the data store/) {
        $id = undef;
        tie %session, 'Apache::Session::File', $id,
            { Directory => "$cartInfoPath",
              LockDirectory => "$cartInfoPath"};
    }
}

if ($id == undef) {
    $cookie = $query->cookie( -name=>'SESSID',
                              -value=>$session{_session_id},
                              -expires=>'+1y', 
                      -path=>'/');
    print $query->header(-cookie=>$cookie);
    print "Assigned session ID ".$session{_session_id}."<br>\n";
} else {
    print $query->header();
    print "Not assigned session ID already ".$session{_session_id}." <
+br>n";
}
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Edit by dws to fix formatting and add <code> tags